β/α转变温度附近恒温处理对铸造Ti65合金显微组织的影响  

Effect of Constant Temperature Treatment Near the Transition Temperature ofβ/αon the Microstructure of Cast Ti65 Alloy

作　　者：武朋辉 焦海峰 汪国栋 岳春华 周耀忠 寇宏超[1] WU Peng-hui;JIAO Hai-feng;WANG Guo-dong;YUE Chun-hua;ZHOU Yao-zhong;KOU Hong-chao(State Key Laboratory of Solidification Technology,Northwestern Polytechnical University,Xian 710072,Shannxi,China;Beijing Xinghang Electromechanical Equipment Corporation,Beijing 100071,China)

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072 [2]北京星航机电装备有限公司,北京100071

出　　处：《铸造》2024年第12期1680-1685,共6页Foundry

基　　金：西北工业大学凝固技术国家重点实验室开放课题(SKLSP202201);陕西省创新能力支撑计划(2023-CXTD-47);西北工业大学特色学科项目(G2022WD)。

摘　　要：Ti65是我国自主研发的一种近α型高温钛合金,作为铸造合金使用时其粗大的片层组织难以通过热等静压和热处理工艺进行调控。本文研究了由β单相区冷却过程中在β/α转变温度附近940~1020℃恒温处理对Ti65合金显微组织的影响。结果表明,Ti65合金经960~1000℃/30min恒温处理后α片层出现粗化、碎断现象,形成由粗化、碎断的α片层及细片层组成的“特殊双态组织”,其中,α片层的粗化、碎断发生在高温保温期间,而细α片层则是在随后的冷却过程中形成。960℃/30 min恒温处理后α片层的粗化、碎断最为明显;940℃和1020℃恒温处理过程中片层形貌特征基本不变,仅发生片层厚度的改变。该工作可为调控铸造钛合金的粗大片层组织提供新的思路。Ti65 is a nearαhigh-temperature titanium alloy independently developed in China.When used as a casting alloy,its coarse lamellar structure is difficult to control through hot isostatic pressing and heat treatment processes.This article investigated the effect of constant temperature treatment from the single-phase zone cooling to 940~1020℃of near the transition temperature ofβ/αon the microstructure of Ti65 alloy.The results showed that theαlamellae in Ti65 alloy was coarsened and fragmented after constant temperature treatment at 960~1000℃/30 min,forming a"special bimodal microstructure"consisting of coarsened and fragmentedαlamellae and fineαlamellae.The coarsening and fragmentation ofαlamellae occurred during the high temperature holding period,while the fineαlamellae were formed during the subsequent cooling process.The most obvious coarsening and fragmentation of theαlamellae occurred after 960℃/30 min constant temperature treatment,while the morphological characteristics of the lamellae remained basically unchanged during the constant temperature treatments at 940℃and 1020℃,with only the thickness of the lamellae being altered.This work could provide new ideas for regulating the coarse and large layer structure of cast titanium alloys.

关 键 词：Ti65合金 片层组织 恒温处理 特殊双态组织 

分 类 号：TG146.2[一般工业技术—材料科学与工程]