摘要
本文以纯Mo、Mo-Re和ODS-Mo三种典型钼合金材料为研究对象,利用动态热机械分析仪在25~350℃对不同合金进行频率为200 Hz的简谐振动实验,分析了高温简谐振动过程中典型钼合金的模量变化及断裂行为,揭示了典型钼合金在简谐振动过程中的能量消耗机制与失效机理。结果表明:晶粒尺寸、第二相颗粒和位错运动是影响典型钼合金减振性能的主要因素;细小的Mo-Re合金晶粒拥有更多的晶间摩擦项,使得Mo-Re合金在高温下的减振性能优于其他两种钼合金;晶界处的第二相颗粒会降低ODS-Mo合金的晶界结合力,因此简谐振动引发的微裂纹优先在此处萌生;螺型位错交叉滑移和多晶粒协调微转动是纯Mo和Mo-Re合金简谐振动断裂失效的主要机制,而第二相颗粒钉扎位错和晶界强度的降低是ODS-Mo合金简谐振动断裂失效的机制;细晶强化和弥散强化能通过增加典型钼合金简谐振动回弹能力,有效提升合金的减振性能。
In this work,using harmonic vibration with a frequency and temperature range of(200 Hz,25-350℃)by the dynamic thermomechanical analyzer,the modulus changing process and fracture behavior of typical molybdenum alloys(Pure Mo,Mo-Re and ODS-Mo)were investigated,and the energy consumption mechanism and failure mechanism of the alloys during high-temperature harmonic vibration were revealed comprehensively.The results show that the grain size,secondary phase particles and dislocation motion are the main factors affecting the vibration reduction performance of typical molybdenum alloys.The Mo-Re alloy with fine grains possesses more intergranular friction terms,and its vibration reduction performance at high temperatures is better than those of the other two alloys.The secondary phase particles at the grain boundary reduce the boundary binding force of ODS-Mo alloy,where the simple harmonic vibration crack is preferentially to be initiated nearby.The screw dislocation cross slip and multi-grain coordinated micro-rotation are the fracture failure mechanisms of pure Mo and Mo-Re alloys during simple harmonic vibration.The pinning dislocation of secondary phase particles and the decrease of grain boundary strength are the dominating failure mechanisms of ODS-Mo alloy during simple harmonic vibration fracture.Fine-grain strengthening and dispersion strengthening are certified to be effective ways to increase the simple harmonic vibration resilience and improve the vibration resistance performance of typical molybdenum alloys.
作者
安毅
赵秦阳
贾致远
张勇
陈永楠
徐义库
强迪
张晓
安耿
AN Yi;ZHAO Qin-yang;JIA Zhi-yuan;ZHANG Yong;CHEN Yong-nan;XU Yi-ku;QIANG Di;ZHANG Xiao;AN Geng(School of Materials Science and Engineering,Chang’an University,Xi’an 710064,China;Jinduicheng Molybdenum Co.,Ltd.,Xi’an 710077,China)
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2023年第10期3264-3275,共12页
The Chinese Journal of Nonferrous Metals
基金
陕西省科技重大专项(2020-ZDZX04-02-01,2020-ZDZX04-02-02)
陕西省重点研发计划资助项目(2023-YBGY-465)。
关键词
典型钼合金
简谐振动
裂纹扩展
位错运动
失效机制
typical molybdenum alloy
harmonic vibration
crack propagation,dislocation movement
failure mechanism
