The application of alloy structural steel 4140

    Alloy structural steel 4140, similar to the performance of 4135, due to increased carbon and chromium content of C Cr, thus the strength and hardenability are better than that of 4135 steel after quenching and tempering, have higher fatigue strength and resistance to repeated shocks, low temperature impact toughness is good, and no obvious temper brittleness, generally used in the steel after quenching and tempering.
    4140 alloy steel generally used in the manufacture strength is higher than 4135 and section size is larger important parts, such as axle, gear, connecting rod, gear box, gear, supercharger engine cylinder, spring, spring clip, 1200~2000mm petroleum drill stem joint, fishing tools and instead of the nickel-containing higher modulation steel.

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