SMn433 
 Standard: 
 SMn433 alloy steel Japan JIS G4053: 2003 
 Chemical composition 
 Carbon C: 0.27 ~ 0.34 Si Si: 0.17 ~ 0.37 Manganese Mn: 1.40 ~ 1.80 S S: to allow the residual phosphorus content of ≤ 0.35 P: ≤ 0.35 to allow the residual content of chromium Cr: to allow the residual content of ≤ 0.30 Ni: to allow the residual content of ≤ 0.30 Copper Cu: ≤ 0.30 to allow the residual content 
 Application examples 
 Most of the steel used in the quenched state, in cars, tractors and general machinery manufacturing, and more for Stamping (4 ~ 11 mm plate) make the car beam, beams, and transmission gear, shaft, bolt cold heading, large cross-section of the quenched parts. In addition, the steel can be used as case-hardened steel, used to make the heart of the Department of carburized parts require a higher intensity, such as mining crane and the rear axle journal and so on. 
 Characteristics and Uses 
 Used as a connecting rod, spindle, crank, axle, lever, fan accessories, 15MM diameter less than the cold-heading variety of important bolts and other mechanical components to withstand high stress. In the production of small cross section (diameter less than 20MM) parts, can replace 40Cr steel. 
 Mechanical Properties 
 Sample blank size (mm): 25 Heat treatment: first quenching temperature (℃): 840; coolant: water, a second quenching temperature (℃): - tempering heating temperature (℃): 500; coolant: Water tensile strength σb (MPa): ≥ 785 (80) yield strength σs (MPa): ≥ 635 (65) Elongation δ5 (%): ≥ 12 Reduction of ψ (%): ≥ 45 Impact energy Akv ( J): ≥ 63 impact toughness αkv (J/cm2): ≥ 78 (8) Brinell hardness (HBS100/3000) (annealing or tempering state): ≦ 207 
 Delivery Status 
 Heat treatment (normalizing, annealing, or tempering) or heat treatment delivery, delivery status should be indicated in the contract