两相区加热温度对HSLA100钢组织演变的影响

Effect of Intercritical Heating Temperature on Microstructure Evolution of HSLA100 Steel

研究了碳含量为0.045%的HSLA100贝氏体钢在两相区加热过程中的组织演变特征。结果表明:两相区加热温度决定奥氏体的转变量,而相变产物的形貌特征主要受奥氏体中的碳含量控制;实验钢在700、720、740、760和820℃保温时,钢中奥氏体转变量分别为10%、24%、38%、60%和100%,奥氏体中的碳含量分别为0.345%、0.293%、0.243%、0.193%和0.045%;显微组织为多边形铁素体+M-A岛,随温度的升高,多边形铁素体量逐渐增加。

The evolution of microstructure during intercritical heating region of HSLA100 bainite steel bearing 0.045% carbon content was investigated.The results show that the austenite amount is controlled by intercritical heating temperature and the character of transformation product is mostly controlled by carbon content in austenite.The austenite amount is 10%,24%,38%,60%,100%,respectively and whose carbon content is 0.345%,0.293%,0.243%,0.193%,0.045% in turn when insulated at 700 ℃,720 ℃,740 ℃,760 ℃and 820 ℃.It was found that the matrix microstructure of HSLA100 steel is polygonal ferrite and some M-A island among them,and with the increase of intercritical heating temperature between 700 ℃ and 820 ℃,the amount of polygonal ferrite gradually increases.