Relationship between microstructure and mechanical properties of undercooled K4169 superalloy  

深过冷K4169高温合金凝固组织演变和力学性能的关系（英文）

作　　者：张可人[1] 谢发勤[2] 胡锐[1] 吴向清[2] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,西安710072 [2]西北工业大学航空学院,西安710072

出　　处：《Transactions of Nonferrous Metals Society of China》2016年第7期1885-1891,共7页中国有色金属学报（英文版）

基　　金：Project(2011CB610406)supported by the National Basic Research Program of China

摘　　要：Various undercoolings 14-232 K of bulk K4169 superalloys were obtained by the method of molten glass fluxing combined with superheating cycling and the mechanical properties of undercooled K4169 with as-solidified state were tested. Microstructures and phases composition in undercooled bulk K4169 superalloy were identified by transmission electron microscope （TEM）, scanning electron microscope （SEM） and optical microscopy （OM）. The morphology of dendrites, grain size and intergranular phase all change with the increased undercooling. Meanwhile, the relationship between microstructure of undercooled K4169 superalloy and tensile properties was investigated. The experimental results show that the uniform distribution of Laves phase and the decrease of grain size and intergranular phase content are favorable for the improvement of mechanical properties. The maximum tensile strength and elongation obtained at undercooling of 232 K are 932.2 MPa and 6.5%, respectively.采用循环过热与熔融玻璃净化相结合的方法使K4169高温合金获得了14~232 K过冷度。采用透射电子显微镜（TEM）、扫描电子显微镜（SEM）和光学显微镜等手段研究过冷K4169高温合金枝晶形貌以及相组成。研究发现,枝晶形貌、晶粒尺寸和晶间相都会随着过冷度的增加而发生明显改变。同时,系统研究过冷K4169高温合金凝固组织与力学性能之间的关系。实验结果表明,晶粒尺寸和晶间相含量的减小以及Laves相的均匀分布提高了合金的抗拉强度和伸长率,并且当过冷度达232 K时,合金具有最优力学性能,抗拉强度为932.2 MPa,伸长率为6.5%。

关 键 词：K4169 superalloy UNDERCOOLING Laves phase mechanical properties MICROSTRUCTURES 

分 类 号：TG132.3[一般工业技术—材料科学与工程] TG156.91[金属学及工艺—合金]