摘要
采用EBSD技术系统地研究了扫描间距h对选区激光熔化(SLM)成形Inconel 738合金微观组织、动态再结晶行为、织构演变和力学性能的影响。研究表明,随着h的增加,平行于沉积方向的细长柱状晶晶粒长/径比减小,晶粒的形貌由粗大的细长柱状晶向细小的等轴晶转变,晶粒的取向变得更加随机;随着h的增加,动态再结晶体积分数增加,再结晶区域位错密度和应变低于未再结晶区域;随着h的增加,其铸造织构的类型发生变化,织构主要由Rotated-Goss织构{110}<110>转变为Rotated-Goss织构{110}<110>+Cube织构{001}<100>,Cube织构的强度逐渐增强,而Rotated-Goss织构的强度逐渐减弱;此外,通过选择合适的扫描间距(h=70μm),沉积态Inconel 738合金可获得优异室温力学性能(σy=933 MPa,σuts=1209 MPa,εf=38%),达到良好的强度与塑性匹配。
The effect of hatching distance(h) on the microstructure, dynamic recrystallization(DRX) behavior, texture evolution and mechanical properties of Inconel 738 alloy formed by selective laser melting(SLM) were systematically investigated by electron backscatter diffraction(EBSD) technique. The results show that the aspect ratio of the elongated columnar grains parallel to the build direction decreases and the morphology of grains changes from coarse elongated columnar grains to fine equiaxed grains with the increase of h, leading to orientation of the grains becomes more random. With the increase of h, the dynamic recrystallization volume fraction increases, and the dislocation density and strain in the recrystallized region are lower than those in the unrecrystallized region. With the increase of h, the type of casting texture changes, the texture mainly transforms from Rotated-Goss texture {110}<110> to Rotated-Goss texture {110}<110> + Cube texture {001}<100>, and the intensity of Cube texture gradually increases, while the intensity of the Rotated-Goss texture gradually weakens. Excellent room temperature mechanical properties(σy=933 MPa, σuts=1209 MPa, εf=38%) of the as-deposited Inconel 738 alloy with appropriate hatching distance(h=70 μm) can be obtained, thereby achieving good match of strength and ductility.
作者
许佳玉
丁雨田
高钰璧
孙富豪
胡勇
张东
Xu Jiayu;Ding Yutian;Gao Yubi;Sun Fuhao;Hu Yong;Zhang Dong(School of Materials Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China;State Key Laboratory of Advance Processing and Recycling of Nonferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China;State Key Laboratory of Nickel and Cobalt Resources Comprehensive Utilization,Jinchuan Group Ltd,Jinchang 737100,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2021年第7期2470-2477,共8页
Rare Metal Materials and Engineering
基金
甘肃省科技重大专项(17ZD2GC011)
镍钴资源综合利用国家重点实验室开放课题
兰州理工大学红柳一流学科建设计划
兰州理工大学优秀博士学位论文培育计划。
