热轧不均匀形变对MGH754合金板材组织的影响  

Effect of Non-uniform Deformation on MGH754 Alloy Hot-rolled Plate

作　　者：雷喆[1] 柳光祖[1] 杨峥[1] 

机构地区：[1]钢铁研究总院高温材料研究所,北京100081

出　　处：《热加工工艺》2013年第9期21-23,共3页Hot Working Technology

摘　　要：通过扫描电镜EBSD技术与光学显微镜分析了不同形变量的热轧板材在不同的纵断面上显微组织与小角度晶界数量的变化,研究了板材热轧与退火时的不均匀行为。研究表明:当热轧形变量为84%时,MGH754合金板材纵截面上心部晶粒尺寸大于边部,而小角度晶界比例相反。当热轧变形量为90%时,板材边部局部出现二次再结晶,形成混晶组织,导致心部与边部小角度晶界比例接近。1335℃高温退火后,板材边部均未发生二次再结晶,而心部均发生。小角度晶界比例越大,合金越不易发生二次再结晶。The microstructure and the quantitative change of small-angle boundary of hot-rolled plate with different deformations in different location of longitudinal section were analyzed by using scanning electron microscopy EBSD and optical microscopy. And the heterogeneous behaviors of the alloy plate in hot-rolling and annealing were investigated. The results show that： when hot-rolling deformation is 84%, the grain size of the subsurface in the center is larger than in the boundary, but the proportion of small-angle grain boundaries is opposite; when hot-rolling deformation is 90%, secondary recrystallization is partly appeared in the subsurface of plate and the mixed grains are formed to lead to the proportion of small-angle grain boundary closing to the center. Aider annealing at 1335℃, the subsurface does not occur secondary recrystallization, but the center of the plate occurs. The higher the proportion of small-angle grain boundaries, the more difficult the occurrence of secondary recrystallization.

关 键 词：MGH754合金热轧板材 形变量 小角度晶界 二次再结晶 

分 类 号：TG355.11[金属学及工艺—金属压力加工]