成品退火工艺对Zr-4合金管材显微组织和力学性能的影响  

Effect of final annealing process on microstructure and mechanical properties of Zr⁃4 alloy tubes

作　　者：渠静雯 李博帅 张海芹 石明华 陈秋羽 李洁 王曦 Qu Jingwen;Li Boshuai;Zhang Haiqin;Shi Minghua;Chen Qiuyu;Li Jie;Wang Xi(Western Energy Material Technologies Co.,Ltd,Xi'an Shaannxi 710299,China)

机构地区：[1]西安西部新锆科技股份有限公司,陕西西安710299

出　　处：《金属热处理》2024年第4期95-103,共9页Heat Treatment of Metals

基　　金：陕西省青年人才托举计划(CLG202256)。

摘　　要：通过金相、室温拉伸、室温爆破、扫描电镜(SEM)和透射电镜(TEM)试验研究了不同成品退火工艺对Zr-4合金包壳管显微组织和室温力学性能的影响。结果表明,在480~525℃的温度范围内,Zr-4合金管处于去应力再结晶的中间状态,并随退火温度的升高或退火时间的延长,轧制变形组织向基本再结晶组织转变,再结晶程度逐渐提高,最大晶粒尺寸呈增大趋势,平均晶粒尺寸变化规律不显著;不同退火工艺管材均析出密排六方结构的Zr(Fe,Cr)_(2)和立方结构的ZrFe_(2)两种第二相粒子,Zr(Fe,Cr)_(2)第二相粒子尺寸差异较大且数量占比大,ZrFe_(2)第二相粒子尺寸较小且数量占比小,第二相粒子尺寸随退火温度的升高或保温时间的延长逐渐增大,但第二相结构未发生变化;室温拉伸及爆破强度随退火温度的升高或保温时间的延长呈降低趋势,拉伸断后伸长率和爆破周向延伸率呈增大趋势,变化趋势随管材再结晶程度的不断提高而逐渐变缓,呈非线性变化。Effect of final annealing process on microstructure and mechanical properties of Zr⁃4 alloy cladding tubes were studied by means of metallographic experiments,room temperature tensile experiments,room temperature blasting experiments,scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The experimental results show that the Zr⁃4 alloy is in an intermediate state between stress reliefing and recrystallization,and the recrystallization degree of the Zr⁃4 alloy increases with the increase of annealing temperature or the extension of annealing time within the temperature range of 480℃to 525℃.The maximum grain size increases from rolling deformed structure to basic recrystallization structure,but the variation pattern of average grain size is not significant.Two types of second phase particles,Zr(Fe,Cr)_(2)with dense hexagonal structure and ZrFe_(2) with cubic structure,are precipitated from matrix under different annealing processes.Zr(Fe,Cr)_(2)particles have a significant difference in size and a relatively large proportion in quantity,while the ZrFe_(2) particles have a smaller size and a relatively small proportion in quantity.The size of the second phase particles gradually increases with increase of annealing temperature or extension of holding time,but the second phase structure has not changed.The strength of burst test and tensile test decrease with the increase of annealing temperature or the extension of holding time,elongation after tensile fracture and circumferential elongation after blasting increase and show nonlinear change,the change trend gradually show down with the increase of recrystallization degree of tubes.

关 键 词：成品退火 Zr-4合金管材 显微组织 力学性能 第二相粒子 

分 类 号：TG156.23[金属学及工艺—热处理]