摘要
研究了热处理工艺对热等静压(HIP)K4169合金铸件微观组织及高温持久性能的影响。结果表明,热等静压处理后的K4169合金铸件进行直接时效(DA)处理,不仅可消除Laves相和针状δ-Ni3Nb脆性相析出问题,还能保留热等静压阶段形成的晶内网络状分布的亚微米级透镜状γ″相。HIP+DA工艺制得的试棒持久性能得到明显提高,这是因为亚微米级透镜状γ″相的存在使得其蠕变变形机制呈现多元化特征。蠕变变形过程中不仅存在位错滑移和攀移,还形成了大量的孪晶组织,从而延长其蠕变寿命,表现出优良的持久性能。
Effects of heat treatment on microstructure and stress rupture properties of investment casting K4169 alloy components after hot isostatically pressed(HIP)treatment have been investigated.It is found that amounts ofδ-Ni3 Nb phase with needle-like morphology can be precipitated both at the grain boundaries and in the inter-dendritic region around the carbides for the HIPed specimens with post solution and aging treatment(HIP+STA).However,absence of Laves phase and needle-likeδ-Ni_3 Nb phase precipitated in the inter-dendritic region can be observed for the HIPed specimens with direct aging treatment(HIP+DA),and the submicronγ″phase precipitated during HIP processing is also preserved in theγ matrix.It clarifies that the hot isostatic pressing with direct aging(HIP + DA)treatment process can improve effectively creep rupture properties both in duration time and elongation.It is suggested that the network submicronγ″particles similar to lens is beneficial for creating a large number of annealing twins,which are contributed to its increase in the stress-rupture properties.
作者
凌李石保
韩延峰
王俊
康茂东
孙宝德
Lingli Shibao Han Yanfeng WangJun Kang Maodong Sun Baode(School of Materials Science and Engineering, Shanghai Jiaotong Universit)
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2016年第10期1013-1018,共6页
Special Casting & Nonferrous Alloys
关键词
K4169高温合金
热等静压
热处理
持久性能
K4169Superalloy
Hot Isostatic Pressing
Heat Treatment
Stress Rupture Properties