过冷熔体保温时间对Ni-3.3B合金凝固组织的影响  

Influence of Holding Time for Undercooled Ni-3.3B Melt on Its Solidification Microstructure

作　　者：陈志梦 许军锋[1] 汪肖 王霞[1] 坚增运[1] CHEN Zhimeng;XU Junfeng;WANG Xiao;WANG Xia;JIAN Zengyun(Shaanxi Province Key Laboratory of Photoelectric Functional Materials and Devices,Xi’an Technological University,Xi’an 710021,China)

机构地区：[1]西安工业大学陕西省光电功能材料与器件重点实验室,西安710021

出　　处：《西安工业大学学报》2019年第2期172-178,共7页Journal of Xi’an Technological University

基　　金：国家自然科学基金(51401156;51671151);陕西省科技新星项目(2016KJXX-87);陕西省教育厅科学研究计划项目(16JK1380;18JS050)

摘　　要：为研究熔体过冷保温处理对合金凝固过程和组织的影响,通过调控高频感应熔炼功率,调节Ni-3.3B(质量百分比w/%)合金过冷熔体的保温时间,得到不同保温时间(18～450 s)下Ni-3.3B合金的凝固组织。采用X射线衍射仪对凝固后试样进行物相分析,利用光学显微镜对凝固组织进行观测与分析,通过显微硬度试验表征其力学性能的变化。研究结果表明:Ni-3.3B合金的凝固组织由初生α(Ni)及不同形状的共晶组织(Ni+Ni_3B)组成。随着保温时间的增加,合金中初生α(Ni)分数逐渐增加,规则共晶组织片层间距减小,且分布更均匀;不规则共晶组织分数降低,随过冷熔体保温时间的增加,共晶组织的显微硬度具有增大的趋势。The paper studies the influence of holding time of undercooled alloy on its solidification microstructure.The solidification microstructures of three types of Ni-3.3B alloy obtaimed for different holding times (from 18~450 s) were obtained by adjusting the high frequency induction and the holding time.Their phase components were identified by X ray diffractometer and their solidification microstructures were observed and analyied with an optical microscope.Their mechanical properties were reflected from the microhardness results.The results show that the microstructures of Ni-3.3B alloy are composed of primary α(Ni) and eutectic structures of different shapes (Ni+Ni 3 B).With the increase of holding time,the fraction of primary α(Ni) increases gradually,the lamellar spacing of regular eutectic structures decreases with more uniform distribution.The fraction of irregular eutectic structure decreases,and the microhardness of the eutectic structure increases with the holding time of undercooled melt.

关 键 词：过冷熔体 保温时间 凝固组织 显微硬度 

分 类 号：TG111.4[金属学及工艺—物理冶金]