浇注温度对K465合金组织与力学性能的影响  

Effects of Pouring Temperature on Microstructure and Mechanical Properties of K465 Alloy

作　　者：严志 王振江[2] 桑志茹[2] 仉凤江 侯桂臣[2] 谢君[2] 于金江[2] Yan Zhi;Wang Zhenjiang;Sang Zhiru;Zhang Fengjiang;Hou Guichen;Xie Jun;Yu Jinjiang(AECC Aero Science and Technology Co.,Ltd.;Institute of Metal Research,Chinese Academy of Sciences)

机构地区：[1]中国航发航空科技股份有限公司计量理化中心,成都610503 [2]中国科学院金属研究所,沈阳110016

出　　处：《特种铸造及有色合金》2021年第8期1001-1006,共6页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(51701212,51771191,51971214);辽宁省自然基金资助项目(2019-MS-336);中国科学院科技服务网络计划区域重点资助项目(KFJ-STS-QYZX-079);2018年度泰州市高层次创新创业人才引进计划资助项目;2020年度中国科学院青年创新促进会资助项目。

摘　　要：研究了浇注温度对K465镍基高温合金组织、力学性能和持久性能的影响。结果表明,在1420~1520℃内,随着浇注温度提高,合金的晶粒尺寸发生粗化,组织中的碳化物形貌和分布未发生明显改变,且碳化物中W元素逐渐增加,γ′相长大。经过1210℃×4 h热处理后,组织中的γ′相形状由铸态的不规则形状转变为立方体,并且尺寸明显细化,且不同浇注温度的合金热处理态组织中的γ′相尺寸和形貌基本一致。随着浇注温度提高,合金的强度有下降的趋势,塑性有所提高,持久性能有所改善。合金持久断裂后裂纹的萌生和扩展主要发生在组织中晶界附近。另外,讨论了浇注温度的变化对合金力学性能变化的影响机制。Effects of pouring temperature on the microstructure,tensile properties and stress rupture properties of K465 nickel base superalloy were investigated.The results reveal that with the increase of pouring temperature in the range of 1420℃to 1520℃,the grains are coarsened without significant change in the morphology and distribution of carbides,and the content of W element in MC carbide is increased with theγ′phase growing.After the standard heat treatment(1210℃×4 h),the irregular shape ofγ′phase is converted to the cubic shape,and the size is obviously refined.Moreover,the size and morphology ofγ′phase in the alloys with different pouring temperature are almost the consistent after the heat treatment.With the increase of pouring temperature,the strength of the alloys tends to be decreased with increasing in elongation,and the stress rupture properties are improved.After that,the crack initiation and propagation mainly occur near the grain boundaries.Finally,the mechanism that pouring temperature affects the mechanical properties of the alloy was discussed.

关 键 词：K465合金 浇注温度 晶粒尺寸 拉伸性能 持久寿命 

分 类 号：TG132.3[一般工业技术—材料科学与工程] TG249.5[金属学及工艺—合金]