热处理对国外P92钢显微组织及晶粒度的影响

对国外P92钢进行不同温度(1040、1060、1080 ℃)淬火和1060 ℃淬火+不同温度(740、760、780 ℃)、不同时间(1、3、5、7 h)的回火热处理,研究热处理参数对其显微组织、晶粒度及硬度的影响。结果表明,经淬火后P92钢组织为板条状马氏体+残留奥氏体,随淬火温度的升高,马氏体组织板条逐渐变粗大,平均晶粒度由9级增大至7级。P92钢经1060 ℃淬火后,随着回火温度的升高和回火时间的延长,P92钢硬度逐渐降低,回火马氏体板条逐渐合并并向回火索氏体过渡,且回火过程中碳化物在晶界和晶内析出并不断长大。

Effect of heat treatment on microstructure and grain size of imported P92 steel

Imported P92 steel was treated by quenching at different temperatures (1040,1060,1080 ℃) and quenching at 1060 ℃ plus tempering at different temperatures (740,760,780 ℃) for different time(1,3,5,7 h).Effect of heat treatment on microstructure,grain size and hardness of the steel was studied.The results show that after quenching,the microstructure of the steel consists of lath martensite and retained austenite.With the increase of quenching temperature,the martensite lath gradually becomes coarser and the average grain size increases from grade 9 to 7.After quenching at 1060 ℃,the hardness of P92 steel gradually decreases with the increase of tempering temperature and the tempering time.The tempered martensite lath gradually merges and transfers to tempered sorbite.During the tempering process,carbides precipitate and grow up at the grain boundaries and inside of the grains.