The hot compression curves and deformed microstructures were investigated under various hot deformation conditions in three states:hot isostatic pressing(HIP,A1),HIP+hot extrusion at 1100℃(A2),and HIP+hot extrusion a...The hot compression curves and deformed microstructures were investigated under various hot deformation conditions in three states:hot isostatic pressing(HIP,A1),HIP+hot extrusion at 1100℃(A2),and HIP+hot extrusion at 1150℃(A3).The results show that A2 sample,extruded at 1100℃ with uniform γ+γ′duplex microstructures,demonstrates excellent hot deformation behavior at both 1050 and 1100℃.The true stress-true strain curves of A2 sample maintain a hardening-softening equilibrium over a larger strain range,with post-deformation average grain size of 5μm.The as-HIPed A1 sample and 1150℃ extruded A3 sample exhibit a softening region in deformation curves at 1050℃,and the grain microstructures reflect an incomplete recrystallized state,i.e.combination of fine recrystallized grains and initial larger grains,characterized by a necklace-like microstructure.The predominant recrystallization mechanism for these samples is strain-induced boundary migration.At 1150℃ with a strain rate of 0.001 s^(-1),the influence of the initial microstructure on hot deformation behavior and resultant microstructure is relatively less pronounced,and postdeformation microstructures are fully recrystallized grains.Fine-grained microstructures are conducive to maximizing the hot deformation potential of alloy.By judiciously adjusting deformation regimes,a fine and uniform deformed microstructure can be obtained.展开更多
利用扫描电子显微镜(scanning electron microscope,SEM)、光学显微镜(optical microscope,OM)、拉伸、蠕变、疲劳试验机等研究了一种新型镍基粉末高温合金FGH4113A(WZ-A3)在2种热处理状态下的显微组织和力学性能,为双性能热处理研究提...利用扫描电子显微镜(scanning electron microscope,SEM)、光学显微镜(optical microscope,OM)、拉伸、蠕变、疲劳试验机等研究了一种新型镍基粉末高温合金FGH4113A(WZ-A3)在2种热处理状态下的显微组织和力学性能,为双性能热处理研究提供组织与力学性能依据。结果表明:FGH4113A合金在双性能热处理中,过固溶与亚固溶态组织与力学性能具有明显的双模特性;室温下,亚固溶态相比过固溶态屈服强度高10.6%,800℃下,过固溶态相比亚固溶态屈服强度高11.7%;与同样是亚固溶或过固溶的其它合金相比,FGH4113A的拉伸强度优于ME3合金,与LSHR合金相当;FGH4113A合金在750℃/450 MPa的蠕变变形以位错滑移机制主导,弥散分布的小尺寸硼化物有助于抗蠕变性能的提高,其抗蠕变性能全面超过ME3合金,与LSHR合金相当;过固溶态的粗晶组织在裂纹扩展中具有更长的滑移带,在循环载荷中具有较低的累积损伤,抗裂纹扩展能力优于亚固溶态;过固溶态的裂纹扩展断口呈现穿晶断裂特征,亚固溶态由于细晶粒边界的一次γ′的存在降低了晶界的抗裂纹扩展能力,断口较粗糙,呈现沿晶-穿晶混合断裂特征。展开更多
基金Shenzhen Science and Technology Program(KJZD20230923113900001)Project of Industry and Information Technology Bureau of Shenzhen Municipality(201806071403422960)。
文摘The hot compression curves and deformed microstructures were investigated under various hot deformation conditions in three states:hot isostatic pressing(HIP,A1),HIP+hot extrusion at 1100℃(A2),and HIP+hot extrusion at 1150℃(A3).The results show that A2 sample,extruded at 1100℃ with uniform γ+γ′duplex microstructures,demonstrates excellent hot deformation behavior at both 1050 and 1100℃.The true stress-true strain curves of A2 sample maintain a hardening-softening equilibrium over a larger strain range,with post-deformation average grain size of 5μm.The as-HIPed A1 sample and 1150℃ extruded A3 sample exhibit a softening region in deformation curves at 1050℃,and the grain microstructures reflect an incomplete recrystallized state,i.e.combination of fine recrystallized grains and initial larger grains,characterized by a necklace-like microstructure.The predominant recrystallization mechanism for these samples is strain-induced boundary migration.At 1150℃ with a strain rate of 0.001 s^(-1),the influence of the initial microstructure on hot deformation behavior and resultant microstructure is relatively less pronounced,and postdeformation microstructures are fully recrystallized grains.Fine-grained microstructures are conducive to maximizing the hot deformation potential of alloy.By judiciously adjusting deformation regimes,a fine and uniform deformed microstructure can be obtained.
文摘利用扫描电子显微镜(scanning electron microscope,SEM)、光学显微镜(optical microscope,OM)、拉伸、蠕变、疲劳试验机等研究了一种新型镍基粉末高温合金FGH4113A(WZ-A3)在2种热处理状态下的显微组织和力学性能,为双性能热处理研究提供组织与力学性能依据。结果表明:FGH4113A合金在双性能热处理中,过固溶与亚固溶态组织与力学性能具有明显的双模特性;室温下,亚固溶态相比过固溶态屈服强度高10.6%,800℃下,过固溶态相比亚固溶态屈服强度高11.7%;与同样是亚固溶或过固溶的其它合金相比,FGH4113A的拉伸强度优于ME3合金,与LSHR合金相当;FGH4113A合金在750℃/450 MPa的蠕变变形以位错滑移机制主导,弥散分布的小尺寸硼化物有助于抗蠕变性能的提高,其抗蠕变性能全面超过ME3合金,与LSHR合金相当;过固溶态的粗晶组织在裂纹扩展中具有更长的滑移带,在循环载荷中具有较低的累积损伤,抗裂纹扩展能力优于亚固溶态;过固溶态的裂纹扩展断口呈现穿晶断裂特征,亚固溶态由于细晶粒边界的一次γ′的存在降低了晶界的抗裂纹扩展能力,断口较粗糙,呈现沿晶-穿晶混合断裂特征。