alloy structural steel 12Cr1MoV
standard : GB/T 3077-1988
●features and use scope :
It is used to high pressure ,over-high pressure ,superheater of precritical power station boiler , collecting box and mainly adapt to the catheter smoke .When the temperature arrives 500℃ it still has high heat resistance and oxgey resistance, has long-time for plasticity.The simple manufacturing technique and  good welding ,but sensitive normalizing of cooling speed.580℃ long-time use can make spheroidization of pearlite.

●Chemical composition :
 C : 0.08～0.15
 Si: 0.17～0.37
 Mn: 0.40～0.70
 S : allow remains content≤0.035
P : allow remains content≤0.035
 Cr: 0.90～1.20
Ni: allow remains content≤0.030
 Cu: allow remains content≤0.030
 V : 0.15～0.30
 Mo: 0.25～0.30

●mechanical properties
 tensile strength σb (MPa): ≥490(50)
yield strength σs (MPa): ≥245(25)
extensibility δ5 (％): ≥22
reduction of area ψ (％): ≥50
ballistic work Akv (J): ≥71
notched bar impact strength αkv (J/cm2): ≥88(9)
rigidity : ≤179HB
specimen size: specimen size of rough 30mm
●heat treatment regime and metallurgical structure:
heat treatment regime : quenching 970℃,air cooling;backfire 750℃,air cooling.
metallurgical structure: : bainite+ferrite.

●deliver position : heat treatment(normalizing, annealing or high-temperature backfire)or no heat treatment, this should be shown on the contract.