Alloy Steel: 4140 Executive Standard: ASTM A29/A29M-04 4140 What is the material: 4140 alloy steel, this steel has good workability, processing small deformation, fatigue performance is quite good, and so is the hardenability of steel, 4140 after heat treatment has a good strength and good mechanical properties, good process, finished product rate with a maximum temperature of 427 degrees Celsius. 4140 chemical composition: chemical composition, 4140 carbon (C) 0.38 ~ 0.43, manganese (Mn) 0.75 to 1.00, phosphorus (P) ≤ 0.030, sulfur (S) ≤ 0.040, Nickel (Ni) ≤ 0.030, chromium (Cr) 0.80 ~ 1.10 ● Features and Scope: strength, high hardenability, toughness, quenching deformation, high temperature strength and high creep rupture strength. Requirements for the manufacture of high strength steel than 35CrMo and quenched forging greater cross-section, such as a big locomotive traction gears, supercharger gear, rear axle, a great link by the load and spring, can also be used 2000m deep drill pipe joints and the following oil and salvage tools. 4140 alloy steel strength, high hardenability, toughness, and quenching of small deformation, high temperature strength and high creep rupture strength. 4140 alloy steel with mechanical properties, tensile strength σb (MPa): ≥ 1080 (110), yield strength σs (MPa): ≥ 930 (95), elongation δ5 (%): ≥ 12.