高温热暴露对Ti60钛合金高周疲劳性能的影响  

Effect of high temperature thermal exposure on high cycle fatigue performance of Ti60 titanium alloy

作　　者：张少平 郭会明 赵子博[2] 吴晨 田伟 钟燕 徐建伟 曾卫东[3] ZHANG Shao-ping;GUO Hui-ming;ZHAO Zi-bo;WU Chen;TIAN Wei;ZHONG Yan;XU Jian-wei;ZENG Wei-dong(AECC Sichuan Gas Turbine Establishment,Chengdu 610500,China;Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;School of Materials Science and Engineering,Northwestern Ploytechnical University,Xi’an 710072,China)

机构地区：[1]中国航发四川燃气涡轮研究院,四川成都610500 [2]中国科学院金属研究所,辽宁沈阳110016 [3]西北工业大学材料学院,陕西西安710072

出　　处：《材料热处理学报》2024年第7期69-78,共10页Transactions of Materials and Heat Treatment

基　　金：“两机”专项基础研究(J2019-VI-0005-0119)。

摘　　要：研究了高温热暴露对Ti60钛合金室温旋转弯曲高周疲劳性能的影响,通过分析试样的表面特征和内部组织,阐明了疲劳性能变化的原因。结果表明,600℃×100 h热暴露后合金的室温强度升高、塑性下降,室温旋转弯曲高周疲劳强度由470 MPa提升至543.3 MPa。疲劳性能的变化是由表面特征和内部组织变化共同引起的,热暴露导致试样表面产生由TiO_(2)及Al_(2)O_(3)组成的氧化膜,表面粗糙度增加、质量变差,对疲劳性能产生不利影响;同时,热暴露致使合金中α_(2)相和硅化物的析出数量增加,且尺寸增加,析出相的变化使得合金强度增加,并进一步提升疲劳强度。综合两方面作用,析出相对旋转弯曲高周疲劳强度的提升强于表面粗糙度增加所产生的不利影响,是疲劳性能提高的主要因素。Effect of high temperature thermal exposure on high cycle fatigue performance of Ti60 titanium alloy during room temperature rotational bending was studied.By analyzing the surface characteristics and internal structure of the samples,the reasons for the changes in fatigue performance were explained.The results show that after thermal exposure at 600 ℃ for 100 h,the room temperature strength of the alloy increases while the plasticity decreases,and the high cycle fatigue strength during the room temperature rotating bending increases from 470 MPa to 543.3 MPa.The changes in fatigue performance are caused by both surface characteristics and internal structural changes.Thermal exposure leads to the formation of an oxide film composed of TiO_(2) and Al_(2)O_(3) on the surface of the specimen,resulting in an increase in surface roughness and a decrease in surface quality,which has an adverse effect on the fatigue performance.At the same time,thermal exposure causes an increase in the precipitation amount and size of α_(2) phase and silicides in the alloy,and the change in precipitates leads to an increase in the strength of the alloy and further enhances its fatigue strength.Taking into account both factors,the improvement of rotational bending high cycle fatigue strength caused by precipitated phases is larger than the adverse effects caused by surface roughness increase,which is the main factor for the improvement of fatigue performance.

关 键 词：Ti60钛合金 热暴露 高周疲劳性能 析出相 表面特征 

分 类 号：TG146.2[一般工业技术—材料科学与工程]