12CrMo 

 12crmo representation Grade: 12CrMo Standard: GB / T 3077-1988 Digital Code: A30122 corresponding foreign standards: JIS G4053: 2003 A29M: 2005 ISO 683-18:1996 
 12crmo Introduction 
 ● Features and Scope: is the thermal strength pearlitic steel, cold plastic strain and may have good machinability, weldability acceptable. Parameters for the manufacture of steam leading up to 510 ℃ tube wall temperature of 540 ℃ of heat pipes, etc., can also produce a variety of flexible working under high temperature components. 
 Chemical composition 
 ● Chemical Composition: C: 0.08 ~ 0.15 Si Si: 0.17 ~ 0.37 Manganese Mn: 0.40 ~ 0.70 S S: agreed residual phosphorus content ≤ 0.035 P: ≤ 0.035 promise residual content of chromium Cr: 0.40 ~ 0.70 Ni: to agree the residual content of ≤ 0.030 Copper Cu: Mo promised residual content ≤ 0.030 Mo: 0.40 ~ 0.55 
 Mechanical Properties 
 ● Mechanical Properties: Tensile σb (MPa): ≥ 410 (42) yield strength σs (MPa): ≥ 265 (27) Elongation δ5 (%): ≥ 24 Reduction of area ψ (%): ≥ 60 
 Impact energy Akv (J): ≥ 110 impact toughness αkv (J/cm2): ≥ 137 (14) Hardness: ≤ 179HB sample size: Sample size of 30mm rough 
 Heat treatment specifications 
 ● Heat treatment and microstructure specifications: Heat treatment specifications: quenching 900 ℃, air-cooled; tempering 650 ℃, air cooling. ● Delivery status: to heat treatment (normalizing, annealing, or tempering) or heat treatment delivery, delivery status should be indicated in the contract. Edit this paragraph 12crmo representation 
 ① steel beginning of the two numbers indicate the carbon content of steel, the average carbon content of the very few that, as 40Cr, 25Cr2MoVA alloy steel pipe ② main alloying elements, in addition to individual micro-alloying elements, in general, to a few percent said. When the average alloy content of <1.5%, the steel elements are generally marked only symbols, not marked content, but prone to cause confusion in those special 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%, 0.9-1.2% for the latter, all the remaining ingredients the same. When the average content of alloying elements ≥ 1.5%, ≥ 2.5%, ≥ 3.5% ... ..., the symbol of the element content should be marked on the back, can be expressed as the corresponding 2,3,4 ... etc. For example 18Cr2Ni4WA. ③ steel vanadium V, Ti Ti, Al AL, boron B, RE alloys of rare earth elements are micro-alloying elements, although very low levels, should bid out in steel. For example 20MnVB steel. To 0.07-0.12% vanadium, boron 0.001-0.005%. ④ High quality steel in the steel should be added the last "A", as distinct from the general high quality steel. ⑤ special purpose alloy steel, steel, known (or suffix) on behalf of the steel uses symbols. For example Lo dedicated 30CrMnSi riveting steel, steel, said to ML30CrMnSi.