Heat treatment standard of 4140 forged steel

    One, the steps and conditions in the heat treatment of 4140 forged steel:
A, normalizing:
Normalizing temperature at 858 °C ~ 912 °C, and maintain the temperature within the specified time. Cooling in air.
B, quenching:
1, temperature Requirements: heated to 816 °C ~ 871 °C, and maintain the temperature within the specified time.
2, the cooling medium requirements: generally uses oil cooling.
C, tempering:
Tempering temperature is not lower than 552 °C, and maintain the temperature within the specified time. The holding time according to the following method to calculate.
1. If the material size less than 2 inches: heat preservation time is not lower than 60 minutes.
2. The material of size greater than two inches: at least 30 minutes per inch (or at least 12 minutes per centimeter) to calculate the holding time. (Material size according to the maximum cross-sectional dimension calculation)
To record the detailed process of heat treatment of 4140 steel (including heating time, heating rate, graphs and charts, furnace type, heat preservation time, cooling mode and other related information), and written the heat treatment report, furnace No. of heat treatment should also be recorded in the material identification certificate.
    Two, ultrasonic testing:
After heat treatment of 4140 forged steel, the removal of the epidermis by mechanical processing way, and then subjected to ultrasonic testing, ultrasonic testing surface roughness of the surface is not more than Ra6.3. Ultrasonic testing equipment, personnel and detection methods, refer to ASTM SA 388-2004 edition, a single defect is less than Φ3.2mm, multiple defects is less than Φ1.6mm. Defects allowed in a non-machined surface, machined surfaces must not have any flaws.
    Three, hardness test:
1, the hardness testing methods and requirements in accordance with ASTM E10 and ASTM E18 requirements.
2, hardness test results must be recorded in the test report, and noted in the material identification certificate.

songsxinblog
The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_49.html, reproduced please specify

The structure and properties of 1.2379 die steel

     1, The characteristics of 1.2379 die steel
     1.2379 steel by conventional smelting, organizational structure is precision, is cold work tool steel, high wear resistance, good stability, good hardenability and hardness, good compressive strength and good toughness.
     2, Typical chemical composition (mass fraction,%)
     C1.50 ~ 1.60, Cr11.00 ~ 12.00, Mn0.15 ~ 0.45, Si0.20 ~ 0.60, P≤0.030, S≤0.030, Mo0.70 ~ 0.90, V0.90 ~ 1.10.
     3, Refer to the corresponding steel No.
     China GB standard steel No. Cr12Mo1V1, American AISI / ASTM standard steel No. D2, Japan JIS standard steel No. SKD11, German DIN standard steel No. X155CrVMo121, German DIN standard material number 1.2379 steel.
     4, The physical Properties of 1.2379 die steel
     Temperature 20 ~ 100 °C / 20 ~ 200 °C / 20 ~ 300 °C / 20 ~ 400 °C / 20 ~ 500 °C, coefficient of linear expansion 10.5 × 10-6K-1 / 11.0 × 10-6K-1 / 11.0 × 10- 6K-1 / 11.5 × 10-6K-112.0 × 10-6K-1.
     5, Temperature 20 °C / 350 °C / 700 ℃, thermal conductivity 16.7 [W / (mK)] / 20.5 [W / (mK)] / 4.2 [W / (mK)].
Quenching, tempering specification
The quenching temperature 980 ~ 1000 °C, gas cooling / oil cooling / 500 °C nitrate cooling.
The quenching temperature 1020 ~ 1040 °C, gas cooling / oil cooling / 500 °C nitrate cooling.
The quenching temperature 1060 ~ 1080 °C, gas cooling / oil cooling / 500 °C nitrate cooling.
Tempering temperature 180 ~ 300 °C / 500 ~ 570 °C, tempering time 1h / 20mm, at least 2 hours, still air cooling.
Typical application: suitable for making mold, extrusion mold stamping die.

songsxinblog
The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_48.html, reproduced please specify

The casting properties of mould steel 1.2344

     Since the mould steel 1.2344 is a kind of multi element composite medium carbon alloy steel, it's contains more alloy elements Mo、V、Cr, make the solidification temperature of liquid alloy decreased, resulting in the crystallization temperature range increases, the casting performance is poorer. The following two tables are the mobility and linear shrinkage of 1.2344 steel. Tests showed, 1.2344 steel pouring temperature control in 1 530 ~ 1 630 ℃ is appropriate, its linear shrinkage be similar to ordinary carbon steel. By the electroslag remelting process can decrease the solidification temperature interval, improve the inner quality of 1.2344 mould steel, improve the toughness of casting mould.

Mobility
Casting type	Pouring temperature/°C	Overheating temperature/°C	Helix length/mm
Sand mold	1530	70	260
Sand mold	1588	128	350
Sand mold	1670	210	475
Sand mold	1700	240	760

Linear shrinkage(%)
Projeck	Parameter
Free shrinkage	1.68
Blocked shrinkage	1.29

songsxinblog
The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_47.html, reproduced please specify

Can 40Cr replace the P20 mould steel

     P20 steel is a kind of plastic mold steel. P20 steel is mainly used in plastic mold and die casting mold material of low melting point metal. The purity of P20 mould steel is high, with good machinability and mirror grinding performance, made of high precision mold, never deformation, high tenacity.
     40Cr is a commonly used alloy structural steel, the tensile strength, yield strength and hardenability is higher than 1040 steel, but its welding is limited, may crack formation.  It can be made of quenched and tempered parts. After surface quenching, 40Cr can be made a part of load and wear resistance are high and impact force is small, such as gears, sleeves, shafts, crankshafts, etc..
     40Cr also belongs to the nitrided steel, it contains beneficial elements to nitriding. After nitrogen treatment, surface hardness of 40Cr is high, the highest reached 72 ~ 78HRA (43 ~ 55HRC).
     If the P20 mould steel nitriding treatment, its surface microstructure is high hardness. After nitriding surface hardness reaches 650-700HV (57-60HRC), the service life of the die can reach more than one million times, the characteristics of the nitride layer has dense structure, smooth, mold release properties and the anti wet air and salty liquid corrosion performance can be improved.
     Previously, most of the APG die is used 40Cr, and then gradually being replaced by P20 steel. From the processing performance for P20 steel processing performance is better than the 40Cr. From the service life of the die, the frequency of use of P20 steel is 5~10 million times, and the frequency of use of 40Cr is 50000 times.

songsxinblog
The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_46.html, reproduced please specify

The important elements of 4130 alloy structural steel

     4130 alloy structural steel is a low alloy heat-resistant steel, with good mechanical properties and resistance to hydrogen at room temperature and high temperature. The main alloy elements in steel are molybdenum, chromium, vanadium, silicon, boron ect.
     Alloying element molybdenum is very important in 4130 steel , it greatly improve the thermo strength of the steel, maintaining sufficient strength at high temperature, and can refine the grain and prevent overheating tendencies of 4130 steel.
     However, if only containing molybdenum in steel, the carbon will gather into the graphite and precipitation in the long-term high temperature, the performance deterioration. In order to eliminate this kind of tendency, often while adding chromium in 4130 alloy structural steel.
     Chromium can enhance thermo strength, high temperature oxidation resistance and corrosion resistance of 4130 steel. Because the chromium can be formed oxide film of dense and strong adhesion on the surface of the steel, preventing the internal metal continued to be oxidation or corrosion. In steel the chromium content is higher, then oxide film more dense , antioxidant and corrosion resistance is better.

songsxinblog
The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_45.html, reproduced please specify

How to prevent cracking of 1.2738 plastic mould steel

    In order to prevent excessive stress cracking of caused by the mold, should be performed 150 ~ 200 ℃ tempering. After the flame hardening, surface hardness can reach 45 ~ 50HRC. Note that, before the flame hardening treatment, 150 ~ 200 ℃ preheating of mould to prevent cracking of the mould.
    1.2738 plastic mould steel is the German DIN standard, vacuum degassing and ESR, steel pure quality, the thickness ≥500mm, its hardness is still evenly; sulfur and gas content is very low (S≤0.005%), mirror-polished performance is excellent, etch and EDM processing performance is good; the pre hardened state supply, do not need to reheat treatment can be directly processing; has excellent processing performance, easy cutting and polishing, stress relief annealing and surface nitriding treatment, size and hardness change little.
    You can use oxygen-acetylene flame heating method perform local hardening for 1.2738 plastic mould steel. The need to hardened parts, heating to light red (850 ~ 950 ℃), and then cooled in the air.
    1.2738 steel surface nitriding can improve the hardness of the surface organization. Nitriding surface is smooth and compact. It has good corrosion resistance. Conducive to product demould and improve production efficiency.

songsxinblog
The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_44.html, reproduced please specify

The characteristics of alloy structure steel 4340

     Alloy structure steel 4340 has high strength, high toughness and good hardenability. When hardened reaches half martensite hardness (HRC45), water quenching critical quenching diameter for Φ ≥100mm, critical quenching oil quenching diameter for Φ ≥75mm; when hardened to 90% martensite, water quenched critical diameter for Φ 80 ~ 90mm, oil quenched critical diameter for Φ 55 ~ 66mm. AISI 4340 alloy steel has anti-overheating and stability, but the white spot high sensitivity, temper brittleness, poor welding, high temperature preheating before welding, eliminate stress after welding.
     The main purpose of alloy structure steel 4340: manufacture of turbine gears, gear ring, the whole forging rotor. Engine connecting rods, valve. High strength, high toughness, a greater cross-sectional size forgings such as forged part of wind generator, drive eccentric shaft of horizontal type forging machine, crankshaft of forging machine etc.. Automobile, airplane special wear-resistant parts etc..

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_43.html, reproduced please specify
songshunblog

Hot work die steel H13 component and nature

     H13 steel containing chromium, molybdenum, vanadium, silicon, manganese. The effect of alloy elements are as follows:
     Chromium: chromium can form chromium carbides in the steel, can improve the high temperature strength and wear resistance of the steel, the C curve shifts to the right, to improve the hardenability and tempering stability of hot work die steel H13. Chromium and other carbide forming elements give steel has high hardenability and resistance to softening ability, so H13 steel can be hardened in condition of air cooling. In the 6barN2 gas vacuum processing conditions can harden diameter is 160mm. But add chromium, carbides will increase the inhomogeneity, the steel will appear in the metastable eutectic carbide. Chromium content increased to improve thermal strength of the material, but the toughness of adverse.
     Mo: can improve the high temperature hardness and the hardenability of the steel. In addition, molybdenum can hinder the austenite grain growth, thereby to refine the crystal grain, reduce the temper brittleness.
     Vanadium: Vanadium to form carbides is easier than the chromium and molybdenum, dissolved in solid solution of iron is extremely small. Vanadium carbides so that the steel has good hot hardness, and refine the grain, improve the wear resistance of hot work die steel H13.
     Si: Silicon has strengthening effect is very good for ferritic solid solution replacement, second only to the phosphorus, but also to some extent reduce the steel toughness and plastic. The general will be restricted in the range of steel deoxidation need. If the Si as alloy elements added to steel, the amount is generally not less than 0.4%. Silicon can also improve the tempering resistance. Si can reduce the diffusion rate of carbon in ferrite,  the precipitation of carbides is not easy to aggregation when tempering, the increase of tempering stability. In addition, silicon is easy to make the steel presents zonal organization, makes the lateral performance of the steel than the longitudinal performance is poor,  also increased the brittle transition temperature of steel. Si also increased decarburization sensitivity of steel, but the Si is beneficial to improve the high temperature oxidation resistance of the mold steel H13 steel.
     Mn: Manganese can change the nature and shape of oxide when during solidification of hot work die steel H13. At the same time it has a greater affinity with S, can prevent formation of low melting point sulfides "FeS" at the grain boundaries, and formation of a certain plastic MnS, thereby eliminating the harmful effects of sulfur, improve hot workability of the steel. Mn has a solid solution strengthening effect, thereby enhancing the ferrite and austenite strength and hardness. Although the solid solution strengthening effect is lower than carbon, silicon and phosphorus, but the ductility of the steel is almost not affected. In the "ferrite - pearlite" type steels, only Mn can increase the yield strength and the cold-brittle transition temperature changes to a minimum.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_42.html, reproduced please specify
songshunblog

What is the D2 die steel

     D2 steel is America grades, belongs to the high wear resistance, small deformation of cold work die steel. This paper introduces the D2 die steel grades, chemical composition, performance , use for you.  songshunblog
     First, corresponding grades. D2 tool steel American ASTM / UNS designations D2, Chinese GB standard grades for Cr12Mo1V1, the International Organization for Standardization (ISO) standard grades 160CrMoV12, German DIN standard material number 1.2379, DIN grades X155CrMoV12-1, French NF standard grades X160CrMoV12, United Kingdom BS standard Grade BD2, Japanese JIS standard grades SKD11.
     Second, the chemical composition. The main chemical composition of D2 die steel (mass fraction):
     Carbon (C) - 1.50%
     Silicon (Si) - 0.35%
     Chromium (Cr) - 12.00%
     Manganese (Mn) - 0.35%
     Molybdenum (Mo) - 1.00%
     Vanadium (V) - 1.00%
     Phosphorus (P) - 0.03%.
     There may be differences in different regions.
     Third, performance. After heat treatment D2 steel hardness up to 60HRC, ledeburite steel with high carbon and chromium, has high hardenability and hardening capacity and high wear resistance; high temperature oxidation resistant. Accession to the Mo, V in composition, changes the morphology of ledeburite, toughness and wear resistance superior to Cr12MoV die steel, to some extent, improve the life of the mold.
     Fourth, use. D2 tool steel widespread use, and can be used for:
     1, Compressors for refrigerators and other appliances rear cover drawing die, quenching hardness 56 ~ 58HRC.
     2, In order to improve the service life of D2 die steel, by adding rare earth method, the wear resistance and impact toughness of the steel are greatly improved.
     3, Can be used to replace the traditional Cr12MoV steel.
     4, Can be used for rolling wheels, a clutch adjusting plate cold stamping die.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_41.html, reproduced please specify

What is the use of 1.2080 die steel

    The 1.2080 die steel is a better cold die steel of wear resistance. High-carbon, high-chromium alloy tool steel, vacuum degassing, refined, pure steel, have a good hardenability, and the quenching deformation is small. The steel is easy turning.
    What is the use of 1.2080 die steel? We introduce its use for you.
    Suitable for manufacturing circular saw, general metal stamping dies, the cold pressing tool of the complex shape, molding roll.
    The fine blanking, cold forging, cold extrusion, drawing die, cold heading die, and so cold mold.
    Deep drawing forming die, scissors mold.
    Sheet thickness ≤2mm, efficient blanking die, stamping die and pressure die.
    The 1.2080 steel can also manufacture a variety of sharp scissors, mosaic blades and senior gauge etc..
    Thread rolling die and wear-resistant slider.
    Hot trimming die, round drum, transformers silicon die, pipe forming rollers, special molding roller, screw Heading molds.
    Thermosetting resin forming die.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_40.html, reproduced please specify
songshunblog

How to quenching and tempering of 4140 alloy steel

     How to quenching and tempering of 4140 alloy steel?
     The quenched and tempered of 4140 alloy steel production process: electric furnace smelting (EBT), LF refining, ingot casting, hot delivery, soaking pit, rolling, slow cooling, the surface peeled, quenching, tempering, steel straightening, cleaning inspection and turned over.
     4140 alloy steel rolling process:
     Use Rolling mill will steel ingot rolled into Φ180mm ~ Φ310mm. Since 4140 steel containing Mn and S, for the steel ingot of hot delivery use the soaking temperature 1260 ℃ in the production process, soaking time 3h, so you can make the steel ingot was burn-through, the steel rolling uniform deformation. Then the steel into the slow cooling pit slow cooling 60h, and then peeled surface treatment, and then quenched and tempered.
     4140 alloy steel quenched and tempered process:
     Before quenching, need to check whether there are cracks in the surface of the AISI 4140 steel, to prevent the quenching process since the steel surface crack lead to quenching crack.
     Steel quenching in bell-type furnace, installed furnace capacity controlled at about 20t, uniform heating to (890 ± 10) ℃, average temperature, heat preservation. Before quenching, tank filled with water and maintain a certain flow rate, water temperature is 10 ~ 40 ℃. From the baked to enter the water time is controlled within 10min. Steel was hanging out from the water every 2min, and then into the water. The quenching time a total of 30min, When leave the water, the steel surface temperature at 200 ℃. Steel after quenching, tempering as soon as possible. Tempering temperature of 580 ℃, the average temperature insulation 6 ~ 8h. After baked, in the sink fast cooling to 400 ℃, and then air cooling.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: {http://www.sc-ledlights.com/news_show_4_22_49.html}, reproduced please specify
songshunblog

What are the methods of DIN 1.2379 steel heat treatment

    Thermal processing of DIN 1.2379 steel:
Start temperature 1050 °C, end temperature 850 °C, furnace cooling.
    Softening annealing treatment:
In the protection of gas, heating to 800~850 °C, then by 10 °C /h speed cooling to 600 °C, then the air cooling, the hardness is less than or equal to 250HBw.
    To eliminate stress treatment:
If want to eliminate the residual stress generated after rough machining, mold should be heated to 650 °C, heat 2h, and then with the furnace cooling to 500 °C, then followed by air cooling.
    DIN 1.2379 steel quenching and tempering:
The first preheating temperature 550 ~ 600 °C, maintained at about 30min per 25mm; the second preheating temperature 800 ~ 850 °C, maintained at about 30min per 25mm; austenitizing temperature 975 ~ 1040 °C, maintained at about 30min per 25mm , oil cooling (40 ~ 70 °C) or gas cooling, cooled to 50 ~ 70mm immediately tempered.
1) low-temperature tempering: tempering temperature 150 ~ 200 °C, each 25mm for about 60min above, air cooling, hardness ≥61HRC. Tempering should choose a lower austenitizing temperature 975 ~ 1025 °C.
2) high-temperature tempering: tempering temperature 480 ~ 540 °C, each 25mm for about 60min or more, air cooling, more than twice tempered, hardness ≥58HRC. Tempering should use a higher austenitizing temperature 1000 ~ 1040 °C.
    Cryogenic treatment of 1.2379 steel:
After hardening, the workpiece is immediately cooled to between -80℃~ -70 °C, maintaining 3 ~ 4h, then tempering. Cryogenic treatment can improve the hardness 1 ~ 3HRC.
    The aging treatment:
Temperature of 110 ~ 140 °C, thermal insulation 25 ~ 100h, in order to ensure that the workpiece size and stability during use.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: {http://www.sc-ledlights.com/news_show_4_22_49.html}, reproduced please specify
songshunblog

How to perform the heat treatment of 1.2344 mould steel

     1.2344 steel as a martensitic hot work die steel, with high toughness and resistance to thermal fatigue performance, moderate resistance to temper softening ability and resistance to melting loss and other comprehensive performance, belongs to medium heat resistant ductile steel, it‘s a kind of ideal hot work die steel. Currently, widely used in manufacturing aluminum die-casting mold many of them are made of 1.2344 mould steel, its not prone to fatigue cracking, even if there is also thin and short fatigue crack is not easy to expand. And anti-strong bond, and the interaction between the molten metal is small, thus ensuring casting can get better visual quality. Because of this the steel also has a high hot hardness, and commonly used in the hot extrusion processing.
     After annealing 1.2344 steel microstructure is mainly pearlite and a small amount of undissolved carbides, very stable supercooled austenite in the pearlite transformation zone. 1.2344 mould steel for containing high chromium steel and has good hardenability, more than 1% of the molybdenum contained in the steel, the steel hardenability it also plays an important role. Since vanadium can form stable carbides in the steel, actually reduces the steel hardenability. A 100mm diameter steel bars in air cooling quenching can also complete quenching. Size is larger than the 100mm mold adopts oil quenching.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_37.html, reproduced please specify
songshunblog

How to heat treatment of P20 plastic die steel

    Improve P20 plastic die steel hardness treatment:
    In order to improve die life up to 80 million times or more, can quenching and tempering way to achieve the implementation of pre-hardened steel. Quenching preheated at 500-600 ℃ 2-4 hours and then at 850-880 ℃ holding a certain time (for at least 2 hours), into the oil cooled to 50-100 ℃ oil cooled, quenched hardness of up to 50 -52HRC. Immediately carried out 200 ℃ low-temperature tempering treatment in order to prevent cracking. After tempering, the hardness can be maintained over 48HRC.
    P20 plastic die steel nitriding treatment:
    Nitrided surface tissue can be obtained with high hardness, surface hardness after nitriding reached 650-700HV (57-60HRC) die life can reach more than one million times, the nitride layer has a dense, smooth characteristics. Improve the mold release properties, P20 steel is improved in the moist air and alkali corrosion resistance.
(Nitriding treatment: refers to a certain temperature under nitrogen atoms penetrate certain media manipulation chemical heat treatment process of the workpiece surface.
After nitriding treatment products with excellent wear resistance, fatigue resistance, corrosion resistance and high temperature properties. Common liquid nitriding, gas nitriding, ion nitriding. Nitriding treatment, also known as diffusion nitriding. Gas nitriding by the Germans Fry in 1923 for the first time to research and development and industrialization. Nitrided article has excellent wear resistance, fatigue resistance, corrosion resistance and high temperature, gradually expanding its scope of application.)

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_36.html, reproduced please specify
songshunblog

The composition and properties of aisi 4130 alloy steel

The chemical composition of the aisi 4130 alloy steel:
Carbon (C): 0.28 ~ 0.33
Silicon (Si): 0.15 ~ 0.35
Manganese (Mn): 0.40 ~ 0.60
Sulfur (S): allows the residual content is less than or equal to 0.040
Phosphorus (P): allows the residual content is less than or equal to 0.035
Chromium (Cr): 0.80 ~ 1.10
Nickel (Ni): allows the residual content is less than or equal to 0.030
Copper (Cu): allows the residual content is less than or equal to 0.030
Molybdenum (Mo): 0.15 ~ 0.25
The mechanical properties of alloy steel 4130:
Tensile strength σb (MPa): ≥930 (95)
Yield strength σs (MPa): ≥785 (80)
Elongation δ5 (%): ≥12
Section shrinkage ψ (%): ≥50
Impact energy Akv (J): ≥63
Impact toughness αkv (J / cm2): ≥78 (8)
Hardness: ≤229HB
Sample size: Sample size is 25mm rough
Heat treatment specifications: quenching 880 ℃, water cooling, oil cooling; tempering 540 ℃, water cooling, oil cooling.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_35.html, reproduced please specify
songshunblog

Introduction of structural steel 4130 steel

    The structural steel 4130 steel with high strength and toughness, high hardenability. In the oil, the critical quenching diameter 15 ~ 70mm. The structural steel 4130 steel hot strength is also good, at below 500 ℃ with a sufficiently high temperature strength, But the strength was significantly decreased at 550 ℃. When the lower limit of the content of alloying elements, the welding is quite good, but the content of alloying elements is close to the upper limit, the welding performance medium.  And the need to preheat to 175 ℃ above before welding. Good machinability of the 4130 steel, cold deformation plasticity medium. When the heat treatment, has a first temper brittleness in the range of 300 ~ 350 ℃, may form white spots.
    The structural steel 4130 steel is typically used in quenched and tempered condition. In medium-sized machinery manufacturing industry mainly for the manufacture of large cross-section, parts working under high stress conditions, such as shafts, spindles and steering wheel to withstand high loads, bolts, studs, and other gear. In the chemical industry for the manufacture of welded parts, welded structure consisting of plates and pipes. For the manufacture high-pressure pipe at containing nitrogen and hydrogen media work and the temperature does not exceed 250 ℃. Fasteners used in steam turbines, boilers manufactured manufacturing work below 450 ℃, below 500 ℃ under high pressure flange and flange cover.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_25.html, reproduced please specify
songshunblog

The performance of the 1.2738 mould steel

    The 1.2738 mould steel is manufactured in accordance with German DIN standard, with relatively superior mechanical properties in similar grades of steel, and good processability, mainly used for the production of hot work die processing, where the most common of plastic mold. In addition, special pre the steel hard treatment make it in the factory when has better hardness, can remove the mold production and processing in the heat treatment of links, improve economic benefits.
    The main performance of the 1.2738 mould steel: Material uniform hardness; excellent polishing performance; excellent machining performance; pre-hardened plastic mold steel; may be subjected to nitriding; suitable surface treatment, such as: plated Cr.
    The physical properties of the 1.2738 steel (Sample Hardness: 340HBW, at room temperature and high temperature conditions):
1) Temperature: 20℃ / 200℃ / 400℃, a density 7.8g/cm, 7.75g/cm, 7.7g/cm.
2) Temperature: 20 ~ 200℃ / 20 ~ 400℃, linear expansion coefficient 12.6×10K / 13.5×10K.
3) Temperature: 20℃ / 200℃ / 400℃, the thermal conductivity 29W·(m·K) / 29.5W·(m·K) / 31W·(m·K).
4) Temperature: 20℃ / 200℃ / 400℃, the elastic modulus 205000MPa / 200000MPa / 185000MPa.
    The mechanical properties of the 1.2738 mould steel (sample hardness 340HBW):
1) Temperature: 20℃ / 200℃ / 400℃, tensile strength 1100MPa / 1050MP8 / 850MPa.
2) Temperature: 20℃ / 200℃ / 400℃, conditions yield strength 980MPa / 925MPa / 770MPa.
3) Temperature: 20℃ / 200℃ / 400℃, section shrinkage rate 49% / 51% / 52%.
4) Temperature: 20℃ / 200℃ / 400℃, an elongation 13% / 14% / 16%.
5) Temperature: 20℃ / 200℃ / 400℃, impact toughness (≥) 20J/cm, 32J/cm, 42J/cm.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_34.html, reproduced please specify
songshunblog

AISI 4340 steel heat treatment guide

     Performance: the AISI 4340 steel is a high hardenability steel, AISI 4340 steel heat treatment hardenability than any kind of steel in the AISI standard of the higher. When the elements are concentrated, hardenability is within the allowable range, the upper curve of hardenability essentially become a straight line, this indicates that the AISI 4340 steel need air quenching in thinner area. In accordance with the precise carbon content, when hardening, Rockwell hardness in the 54-59 range. Due to high hardenability, AISI 4340 steel using traditional welding methods are not suitable, although it can use this old methods, such as electron beam welding. AISI 4340 steel can be forged effortlessly, although its thermal performance than carbon or low-alloy steel is higher, the need to use high power forging machine. The mechanical processing is not very good.
     Forging: heated to 1230℃. After the temperature dropped to 900℃ to stop forging. Cool slowly to prevent cracks.
     Recommended AISI 4340 steel heat treatment operations:
     Normalizing: heating to 870℃. Cooling in air to 565 degrees; or heated to 830 degrees, rapidly cooled to 650 ℃, and hold 8 hours. In order to get the ball structure and heated to 750℃, rapidly cooled to 705℃, and then at a rate of not more than 3℃ per hour was cooled to 650℃, and hold 12 hours. Ball organizational structure is usually easy machining and heat treatment.
     Quenching: 845 degrees at the time, the steel organization becomes austenitic, then oil quenched. In the casting the thin area can be air quenching.
     Tempering: with all high hardenability steel the same, alloy steel 4340 will produce quenching cracks. In the casting to ambient temperature before (38-50℃), they should be placed in tempering furnace. Tempering temperature depends on the desired hardness or comprehensive mechanical properties.
     Nitriding: through nitriding to produce high surface hardness and enhance the anti fatigue performance.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_33.html, reproduced please specify
songshunblog

Mold steel H13 steel performance introduction

    H13 steel is hot work die steel, it is the steel of adding alloying elements on the basis of carbon tool steel. Mold steel H13 steel is the most widely used and most representative of hot work die steel, its main features are as follows:
    Has high hardenability and high toughness;
    Excellent thermal shock resistance, in the workplace can be water cooled;
    H13 steel with moderate abrasion resistance can also be used carburizing or nitriding process to improve the surface hardness, but the thermal shock resistance will be slightly reduced;
    Because of its low carbon content, tempering the secondary hardening ability is poor;
    Mold steel H13 steel has a softening resistance at a relatively high temperature, but the use of temperatures above 540 ℃ (1000 ℉) hardness decreased rapidly. Therefore, the operating temperature of the H13 steel should not exceed 540 ℃;
    The heat treatment deformation is small;
    Medium and high machinability;
    Moderate resistance to decarbonization capacity.
    The comprehensive properties of H13 steel is good in the mesotherm, high hardenability (in the air that can harden), heat treatment distortion probability is lower, the performance and service life is better than 1.2581 steel. Can be used for die forging hammer forging die, aluminum alloy die-casting die, hot extrusion die, high speed precision forging die and forging press mould. It also can be used for the production of an important component of aviation industry.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_32.html, reproduced please specify
songshunblog

D2 steel heat treatment process

    D2 steel heat treatment methods:
    Stress relief annealing: the workpiece after rough machining, heating to 600~650 ℃, thermal insulation for 2 hours, with the furnace cooling to 500 ℃, followed by air cooling.
    Quenching: for the first time preheating, slowly warming the workpiece to 600 ℃, heat 20 minutes. After temperature uniformity, the second time preheating temperature was raised to 850 ℃, incubated for 30 minutes. Finally heated to 1020 ~ 1040 ℃, heat 25 to 40 minutes, followed by air cooling.
    Tempering: immediately tempering after quenching, and tempering at least twice, each holding time is not less than 2 hours.
    D2 steel heat treatment matters needing attention:
    After quenching, should be timely tempering, prevent cracking, and to prevent surface decarburization, for the manufacture of high precision die and gauge of D2 steel should be cryogenic treatment (-70 ℃), and the use of high-temperature tempering, To reduce the workpiece deformation, high temperature tempering temperature 500 ~ 560 ℃, hardness greater than 58HRC.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_31.html, reproduced please specify
songshunblog

The introduction of the mold steel 1.2080 steel

     The mold steel 1.2080 steel is the German D1N standard material number, which corresponds to the Chinese GB standard grade CR12, Japanese JIS standard grade SKD1, U.S. AlSI / SAE standard grade D3. Mold steel 1.2080 steel is a kind of ledeburite steel with high carbon and chromium. It has a high abrasion resistance, hardenability, hardenability, toughness, thermal stability, compressive strength, micro-deformation and excellent overall performance, has good machining and thermal oxidation resistance, wide adaptability. Has a high abrasion resistance, is 3 to 4 times of the general low alloy tool steel. The small deformation hardening.
     Mold steel 1.2080 steel isothermal spheroidizing annealing specification: (850 ~ 870) ℃ × (3 ~ 4) h, with the furnace cooling, (740 ~ 760) ℃ × (4 ~ 5) h isothermal, cooled baked, hardness temperature ≤241HBS, eutectic carbides ≤3 level.
     Ordinary quenching specification: Temperature 950 ~ 1150 ℃, oil quenching, quenching hardness ≥60HRC.
     The 1.2080 steel can be used to make cold working mold of complex shape and working conditions complex. Such as Die punch, thread rolling dies, drawing dies, die cutting, powder metallurgy die, woodworking cutting tools, cold cutting scissors drill sleeve and gauge tool.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_30.html, reproduced please specify
songshunblog

The properties of the structural alloy steel 4140 steel

     Structural alloy steel 4140 steel has good workability, machining deformation small, anti-fatigue performance is quite good, is a medium hardenability steel. After the 4140 heat treatment has good strength and excellent mechanical properties, good technology, finished product rate. Maximum use temperature of 427 degrees Celsius. 4140 steel with high strength and hardenability, good toughness, quenching small deformation, high creep strength and lasting strength at high temperatures. 4140 steel can be used for manufacture forgings of higher strength and greater cross-section, such as a locomotive traction gear, turbocharger transmission gear, rear axle,  the connecting rod and the spring clips of great load, can also be used in less than 2000m deep oil drill pipe joints and fishing tools, and can be used for bending machine die etc..

The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_29.html, reproduced please specify
songshunblog

Introduction of mold steel 1.2379 steel

     The mold steel 1.2379 steel is a high-carbon and high-chromium alloy tool steel, has high hardness and wear resistance after heat treatment, and has a strong hardenability, good dimensional stability. The 1.2379 mold steel is suitable to make high precision and long life of cold work die and thermosetting molding plastic mold.
     The characteristics of mold steel 1.2379 steel are: pure steel vacuum degassing refining process. Ball annealing softening treatment, good cutting performance. Add strengthening elements vanadium, molybdenum, extremely excellent abrasion resistance.
     The 1.2379 steel uses: Sheet thickness no greater than 2MM, efficient blanking die, punch die and pressure die carrier. Scissors, inserts, woodworking blades. Thread rolling die and wear slider. Cold heading die, thermosetting resin molding die. Deep drawing molding die, cold extrusion dies.
     Quenched and tempered to a hardness of 63HRC. Its physical properties at room temperature and high temperature:
1) Temperature 20℃, the density 7700g/cm, the thermal conductivity of 20.0W/(m-K), the elastic modulus 210000MPa.
2) When the temperature of 200℃, the density 7650g/cm, linear expansion coefficient (20℃) 12.2×10K, thermal conductivity: 21.0W/(m-K), elastic moduli 200000MPa.
3) Temperature 400℃, the density 7600g/cm, the thermal conductivity of 23.0W/(m-K), the elastic modulus 180000MPa.

The above article from Songshunsteel official website (http://www.songshunsteel.com/)

The original address: http://www.songshunsteel.com/news_show_27_15_27.html, reproduced please specify

songshunblog

Introduction of mold steel 1.2344 steel

    The characteristics of the mold steel 1.2344 steel: material uniformity, excellent machinability and polishing. High toughness and high ductility. Excellent overall hardening. Good high temperature strength and thermal fatigue resistance. Deformation of heat treatment is very low. Compared to the conventional steel, the 1.2344 steel have better isotropic, each direction has excellent toughness and ductility. The 1.2344 steel is the pressure hot work mold steel. The steel by electroslag remelting, material uniformity, hardenability good, with excellent machining properties and polishing properties, high toughness and plasticity. It has good abrasion resistance and anti high temperature fatigue and heat resistance at high temperature and low temperature.
    Chemical composition of mold steel 1.2344 steel: C 0.38-0.42; Si 0.8-1.2; Mn 0.30-0.50; P≤0.015; S≤0.002; Cr 4.80-5.50; Mo 1.2-1.5; V 0.90-1.10.
    The mold steel 1.2344 steel is mainly used in die casting mould, extrusion die, hot pressing mould. For high wear-resistant plastic mold, such as car tires alloy rings, engine, fishing line wheel.

The original address: http://www.songshunsteel.com/news_show_27_22_28.html, reproduced please specifyThe above article from Songshunsteel official website (http://www.songshunsteel.com/)
songshunblog

About mold steel P20 steel

     P20 steel is a type of plastic mold steel, P20 is the United States grades, which corresponds to Chinese brands: 3Cr2Mo; Germany Grade: 1.2311. Steel types: pre-hardened plastic mold steel. Mold steel P20 steel is suitable for the production of plastic mold and die casting mold material of low melting point metal. This steel has good machinability and mirror-polished performance.
     Mold steel P20 steel chemical composition: Carbon: 0.38; Manganese: 1.30; Chromium: 1.85; Mo: 0.40; sulfur: 0.008.
     P20 steel hardness uniform, with good polished performance and photoetching performance, excellent processing performance. Pure steel vacuum degassing refining process, the requirements for polishing or etch processing plastic mold. Pre hardening treatment, without the heat treatment, can be directly used in mold processing, shorten the construction period. After forging rolling processing, compact structure, 100% ultrasonic inspection, no air hole and needle eye.

blogyuanjing01
The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_26.html, reproduced please specify

Introduction of structural steel 4130 steel

     The structural steel 4130 steel with high strength and toughness, high hardenability. In the oil, the critical quenching diameter 15 ~ 70mm. The structural steel 4130 steel hot strength is also good, at below 500 ℃ with a sufficiently high temperature strength, But the strength was significantly decreased at 550 ℃. When the lower limit of the content of alloying elements, the welding is quite good, but the content of alloying elements is close to the upper limit, the welding performance medium.  And the need to preheat to 175 ℃ above before welding. Good machinability of the 4130 steel, cold deformation plasticity medium. When the heat treatment, has a first temper brittleness in the range of 300 ~ 350 ℃, may form white spots.
     The structural steel 4130 steel is typically used in quenched and tempered condition. In medium-sized machinery manufacturing industry mainly for the manufacture of large cross-section, parts working under high stress conditions, such as shafts, spindles and steering wheel to withstand high loads, bolts, studs, and other gear. In the chemical industry for the manufacture of welded parts, welded structure consisting of plates and pipes. For the manufacture high-pressure pipe at containing nitrogen and hydrogen media work and the temperature does not exceed 250 ℃. Fasteners used in steam turbines, boilers manufactured manufacturing work below 450 ℃, below 500 ℃ under high pressure flange and flange cover.

blogyuanjing01
The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_25.html, reproduced please specify

Introduced the features of 1.2738 steel

    The 1.2738 steel using advanced die steel refining technology, is a vacuum melting Cr-Ni-Mo alloy steel. The features of 1.2738 steel: The steel has excellent polishing and photo-etching performance; excellent machinability; good wear resistance; large mold hardness is uniform, dense tissue; no quenching crack and deformation of heat treatment of risk, without heat treatment, shorten the molding cycle; surface nitriding performance can be good; flame surface hardening treatment, to improve the surface hardness and wear resistance of the die. Die before quenching, must be fully softening annealing. Should be timely tempering after quenching, slow heating.
    In the late precision electrical discharge machining, shall be conducted in small current, high frequency, so as not to damage the mould. After discharge the mold surface should be removed "electric spark grinding white layer", followed by a second tempering at 500 ℃, to remove stress.
    For grinding machining of the mold after tempering, in order to prevent softening of surface, grinding crack, should be noted: sufficient cooling; suitable grinding pressure; reasonable processing technology.
    The 1.2738 steel has good polishing performance, usually by alumina or gypsum polishing. The first is the rough polishing, and then polished with fine abrasive, every change once abrasives, polishing the direction you want to change, and ultimately a polishing time not too long, otherwise it will affect the roughness of the surface of the mold.
    Nitriding can increase the mould surface hardness, improve the wear resistance and corrosion resistance. Although the steel has been pre-hardening treatment, but still can enhance the hardness by heat treatment.

blogyuanjing01
The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_15_24.html, reproduced please specify

Introduction of AISI 4340 steel properties

     AISI 4340 steel is one of the alloy structural steel , also known as alloy steel. It is based on high quality carbon structure steel, properly adding one or several kinds of alloy elements (the total content of not more than 5%) steel made. The AISI 4340 steel properties with high strength, high toughness and excellent hardenability and anti overheating stability, but white has high sensitivity, temper brittleness. Poor weldability, prior to welding need to high temperature preheating, after soldering need to eliminate stress, after adjustment use.
     Mechanical properties of AISI 4340 steel is as follows:
     Tensile strength σb (MPa): ≥980 (100)
     Yield strength σs (MPa): ≥835 (85)
     Elongation δ5 (%): ≥12
     Reduction of area ψ (%): ≥55
     Impact energy Akv (J): ≥78
     Impact toughness αkv (J / cm & sup2;): ≥98 (10)
     Sample size: Sample size is 25mm rough
     Heat treatment: (Quenching temperature: 850 degrees; coolant: oil; tempering temperature: 600 degrees; Coolant: water, oil);
     Steel annealing or tempering condition Brinell hardness GBW≤269
     According to AISI 4340 steel properties, which can be used to make good toughness, high strength, as well as an important regulator of large-size parts, such as heavy machinery and high load shaft. The size of machine shaft large than 250mm in diameter. Helicopter rotor shaft. Turbojet turbine shafts, blades, high load transmission parts. Crankshaft fasteners. And other gear. Can also be used to operate the temperature exceeds 400 ℃ rotor shaft and blades; AISI 4340 steel can also be nitriding treatment, used to manufacture special performance requirements of the important parts, such as shafts, gears, and other fasteners. After quenching or after isothermal tempering can be used for ultra-high-strength steel.

blogyuanjing01
The above article from Songshunsteel official website (http://www.songshunsteel.com/)
The original address: http://www.songshunsteel.com/news_show_27_22_23.html, reproduced please specify