38CrSi, alloy structural steel. Uniform digital code: A21382 Standard: GB / T 3077-1988 
 Physical properties 
 Chemical composition 
 (Wt) (%) Carbon C: 0.35 ~ 0.43 Si Si: 1.00 ~ 1.30 Manganese Mn: 0.30 ~ 0.60 S S: to allow the residual phosphorus content ≤ 0.035 P: ≤ 0.035 to allow the residual content of chromium Cr: 1.30 ~ 1.60 Ni-Ni: allow the residual content ≤ 0.030 Copper Cu: ≤ 0.030 to allow the residual content 
 Mechanical Properties 
 Sample blank size (mm): 25 Heat treatment: first quenching temperature (℃): 900; Coolant: Oil second quenching temperature (℃): - tempering heating temperature (℃): 600; coolant: water, oil tensile strength σb (MPa): ≥ 980 (100) yield strength σs (MPa): ≥ 835 (85) Elongation δ5 (%): ≥ 12 Reduction of ψ (%): ≥ 50 Impact Energy Akv (J): ≥ 55 impact toughness αkv (J/cm2): ≥ 69 (7) Brinell hardness (HBS100/3000) (annealing or tempering state): ≦ 255 Delivery status: to heat treatment (normalizing , annealing or tempering) or heat treatment delivery, delivery status should be indicated in the contract 

 38crsi Overview 
 Key Features 
 This is a high strength, medium toughness of steel, its hardenability slightly better than 40Cr, quenching in oil the critical diameter of 25 ~ 83.5mm; steel cutting can be still good, but the tendency to temper brittleness when heat treatment and cold plastic deformation is low, poor welding. 
 Application examples 
 This steel is usually used after quenching and tempering, the general in order to create a diameter of 30 ~ 40mm and demanding parts. Such as axes, spindle, the tractor into the valve, the internal combustion engine oil pump gear and other requirements of high strength and wear-resistant parts; also produce cold shock tools, such as the top pressure riveting machine