alloy structural steel 12Cr1MoV 15CrMoV5-9, 1.8521
standard:GB/T 3077-1999
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 Celsius 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.580Celsius 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 *b (MPa):>=490(50)
yield strength &s (MPa):>=245(25)
extensibility &5 (%):>=22
reduction of area & (%):>=50
ballistic work Akv (J):>=71
notched bar impact strength &kv (J/cm2):>=88(9)
rigidity :<=179HB
specimen size:specimen size of rough 30mm
heat treatment regime and metallurgical structure:
heat treatment regime :quenching 970Celsius,air cooling;backfire 750Celsius,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.