退火温度对0.2C-1.5Si-1.5Mn-(0.5Cu)TRIP 钢组织的影响

用彩色金相法、X 射线衍射、扫描电镜研究了成分(%)为 0.2C-1.5Si-1.5Mn和0.2C-1.5Si-1.5Mn-0.5Cu TRIP钢 750～780℃不同退火温度对组织的影响。结果表明,含0.5 %Cu TRIP钢750℃、760℃、780℃退火的残余奥氏体体积含量为15.2 %～17.2 % ,770℃退火为15.2 %～15.7% ;不含CuTRIP钢760℃和770℃退火的残余奥氏体体积含量分别为12.5 %～12.9%和14.6 %～15.1% ,低于750℃和780℃退火的奥氏体量分别为17.0 %～17.5%和16.0 %～16.4%。随退火温度由750℃提高至780℃ ,两种钢中的铁素体量由～70%降至～5 0% ,贝氏体量由～10%增至～30%

Effect of Annealing Temperature on Structure of 0.2C-1.5Si-1.5Mn-(0.5Cu) TRIP Steel

The effect of annealing temperature between 750 ℃ and 780 ℃ on structure of two TRIP steel - 0.2C-1.5Si- 1.5Mn and 0.2C-1.5Si-1.5Mn-0.5Cu has been studied by color metallograph method, X-ray diffraction and scanning electron micrograph. The test results showed that for the TRIP steel containing 0.5Cu,the retained austenite volume fraction was 16.2%～17.2% when annealed at 750 ℃,760 ℃ and 780 ℃ and it was 15.2%～15.7% when annealed at 770 ℃;and for free Cu TRIP steel,when annealed at 760 ℃ and 770 ℃,the retained austenite volume fraction was 12.5%~12.9% and 14.6%～15.1% respectively which lower than that fraction 17.0%~17.5% and 16.0%～16.4% when annealed at 750 ℃ and 780 ℃ respectively. With the annealing temperature increased from 750 ℃ to 780 ℃ the ferrite volume fraction in steel decreased from ～70% to ～50%,and the bainite volume fraction in steel increased from ~ 10% to ～30%.