【摘要】 为获得均匀的细晶组织，对GH4730合金进行了多次累积变形试验，并用OM、SEM和EBSD对微观组织进行分析。结果表明，随着变形次数和变形量的增加，合金的再结晶比例逐渐增大，未再结晶晶粒的尺寸和数量逐渐减小。再结晶机制以不连续动态再结晶(DDRC)为主，连续动态再结晶(CDRX)为辅，DDRX主要发生在硬取向晶粒之间，残留的未再结晶晶粒的Taylor因子普遍较大。未再结晶组织中存在大量细小的共格γ′相，较大的不共格γ′相分布在完全再结晶区域的晶界处，其尺寸为1.1～1.4μm。随着变形次数和变形量的增加，一次γ′相逐渐变粗，面积分数显著增大，二次γ′相数量显著减少。更多还原

【Abstract】 In order to obtain a homogeneous fine-grained microstructure, multiple cumulative deformation test for GH4730 alloy were carried out. The microstructure of the alloy after multiple cumulative deformations was analyzed by means of OM, SEM and EBSD. The results reveal that the proportion of recrystallisation gradually increases and the size and number of unrecrystallised grains gradually decrease as the deformation times and amount increase. The recrystallisation mechanism is dominated by discontinuous dynamic recrystallisation(DDRX), supplemented by continuous dynamic recrystallisation(CDRX). The DDRX occurs mainly between the hard oriented grains, and the Taylor factor of the residual unrecrystallised grains is generally larger. There is a large amount of fine coherent γ′ phase in the unrecrystallised microstructure. As the deformation times and amount increase, the primary γ′ phase becomes progressively coarser, with a significantly larger area fraction and a significantly smaller number of secondary γ′ phases.更多还原