Carbon, the C: 0.35 ~ 0.43 Si Si: 1.00 ~ 1.30 Mn Mn: 0.30 ~ 0.60 Sulfur S: allow the residual content of ≤ 0.035 phosphorus P: allow the residual content of ≤ 0.035 Chromium Cr: 1.30 ~ 1.60 Nickel Ni: allow the residual content of ≤ 0.030 Copper Cu : Allow the residual content of ≤ 0.030 
 Mechanical properties 
 Blank sample size (mm): 25 Heat treatment: the first quenching temperature (° C): 900; coolant: Oil quenching temperature (° C): - tempering the heating temperature (° C): 600; coolant: water, oil tensile strength σb (MPa): ≥ 960 (100) yield strength σs (MPa): ≥ 840 (85) elongation δ5 (%): ≥ 12 Reduction of area ψ (%): ≥ 50 Impact Energy Akv (J): ≥ 55 impact toughness the value αkv (J/cm2): ≥ 69 (7) Brinell hardness (HBS100/3000,) (annealing or high temperature tempered condition): ≦ 255 Delivery status: heat treatment (normalizing annealing or high-temperature tempering) or no heat treatment delivery status, delivery status should be indicated in the contract. 
 Edit this paragraph 38crsi Overview 
 Key Features 
 This is a high strength, moderate toughness of steel, hardenability slightly better than 40Cr in the oil critical hardenability diameter of 25 ~ 83.5mm; steel machinability is still good, but have a tendency to temper brittleness in the heat and cold deformation plasticity, poor weldability. 38crsi picture 
 Application examples 
 This steel is usually used after quenching and tempering, the general manufacturing diameter 30 ~ 40mm and demanding parts. Such as axis, the spindle, the intake valve of the tractor, the internal combustion engine's oil pump gear and other requirements of high strength and wear-resistant parts; can be made of the impact of cold work tools such as rivet machine pressure first class. 
 Edit this paragraph, said method 
 ① steel beginning of the two figures, said the carbon content of steel, the average carbon content of the very few, such as 40Cr, 38CrSi alloy tube ② steel alloying elements, in addition to the individual micro-alloying elements, generally a few percent said. When the average alloy content <1.5%, steel, generally mark the element symbol not indicate the content and prone to cause confusion, but in exceptional circumstances, after the element symbol can also be marked with the number "1", such as steel "12CrMoV" and "12Cr1MoV", the former chromium content of 0.4-0.6% and 0.9-1.2%, and the remaining ingredients are all the same. When the average content of alloying elements ≥ 1.5% ≥ 2.5% ≥ 3.5% ... in the back of the element symbols should be marked content, can be said that the corresponding 2,3,4 and so on. For example 18Cr2Ni4WA. ③ steel, vanadium V, titanium Ti, aluminum AL, boron B, rare earth RE alloying elements are micro-alloying elements, although the content is very low, should still be marked in the steel. 20MnVB steel. Vanadium 0.07-0.12%, 0.001-0.005% boron. ④ High quality steel in the steel and finally add the "A", to distinguish them from the general high quality steel. ⑤ special purpose alloy structural steel, steel, dubbed (or suffix) on behalf of the steel use the symbol. Such as Heading a dedicated 30CrMnSi steel, steel ML30CrMnSi. Alloy pipe and seamless pipe between the two existing relationship and differences between them, can not be confused. Alloy pipe steel pipe in accordance with the production of materials used (that is, material) to define the name suggests is alloy tube; seamless pipe steel pipe in accordance with the production process (sew seamless) to define and distinguish it from the seamless tube seam tube, Longitudinal and spiral.