增材制造GH3536合金的高温拉伸及疲劳裂纹扩展性能研究  

High Temperature Tensile and Fatigue Crack Propagation Properties of GH3536 Alloy Fabricated by Additive Manufacturing

作　　者：肖来荣[1,2] 彭振武 蔡圳阳[1,2] 赵小军 钟琦[1] 余华丽[1] 王森 谭威 Xiao Lairong;Peng Zhenwu;Cai Zhenyang;Zhao Xiaojun;Zhong Qi;Yu Huali;Wang Sen;Tan Wei(School of Materials Science and Engineering,Central South University,Changsha 410083,China;Key Laboratory of Nonferrous Metal Materials Science and Engineering,Ministry of Education,Changsha 410083,China)

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]有色金属材料科学与工程教育部重点实验室,湖南长沙410083

出　　处：《稀有金属材料与工程》2023年第3期1015-1021,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51901252);湖南省青年自然科学基金(2019JJ50817);国家重点研发计划(2018YFB1106000)。

摘　　要：采用选区激光熔化技术制备GH3536合金试样,经热等静压和固溶处理后对合金试样的显微组织、高温拉伸性能和不同应力比下的裂纹扩展性能进行了分析。结果表明,经热等静压和固溶处理后合金试样内部存在2种不同大小的等轴晶粒,在晶间存在连续片状分布的M_(23)C_(6)和M_(6)C碳化物。合金试样的拉伸性能随着温度的升高而不断下降,断裂方式由室温下的韧性断裂转变为900℃下的脆性断裂。在不同应力比下,合金试样的裂纹扩展方式主要为穿晶扩展,裂纹扩展速率随着应力比的不断上升而提高,在高应力比下合金内部的疲劳裂纹更倾向于在取向差较小的晶粒内部扩展。GH3536 alloy specimens were fabricated by selective laser melting(SLM).The microstructure,high temperature tensile properties and fatigue crack growth rate of the specimens were investigated after hot isostatic pressing and solution treatment.The results show that there are two kinds of equiaxed grains of different sizes in the alloy samples after hot isostatic pressing and sol ution treatment,and there are continuous lamellar distribution of M_(23)C_(6)and M_(6)C carbides between the grains.The tensile properties of the alloy specimens decrease continuously with the increase of temperature,and the fracture mode changes from ductile fracture at room temperature to brittle fracture at 900℃.Under different stress ratios,the crack propagation mode of the specimens is transgranular propagation.The increase of stress ratio will accelerate the crack growth rate,which is caused by the inclination of fatigue crack propagating through these grains with low grain boundary misorientation.

关 键 词：选区激光熔化 GH3536合金 显微组织 高温拉伸性能 疲劳裂纹扩展 

分 类 号：TG146.15[一般工业技术—材料科学与工程]