【摘要】 增材制造技术为发展高性能高温合金材料及部件提供了新的途径。本工作开发一种适于增材制造工艺条件的γ’相强化CoNi基高温合金，并结合电子束熔化（electron beam melting,EBM）技术的工艺参数优化，制备出无裂纹的合金块体材料。结果表明：扫描速度为2000 mm/s时，合金孔隙率最低，约为0.14%；打印态CoNi基合金显微组织为沿<001>方向生长的柱状晶粒，平均晶粒宽度约为235μm,γ’相体积分数约为30%；经过热等静压及固溶时效处理后，孔隙率进一步降低至约0.09%，柱状晶粒基本没有变化；γ’相的平均尺寸为（70±18） nm，体积分数为（32±3.6）%。室温拉伸实验结果表明，增材制造γ’相强化CoNi基高温合金展示出优异的强塑性配合，展示出良好的工业应用前景。更多还原

【Abstract】 Additive manufacturing provides a new way to develop high-performance superalloys and components. A γ ’-strengthened CoNi-base superalloy suitable for additive manufacturing was developed,and a crack-free block material was prepared by optimizing the parameters of electron beam melting(EBM) technology. The experimental results show that the lowest porosity of the alloy is about 0.14% when the scanning speed is 2000 mm/s. The microstructures of the as-printed CoNi-base alloy are columnar grains growing along the <001> direction,the average grain width is about 235 μm,and the volume fraction of γ’ phase is about30%. After hot isostatic pressing and solution aging treatment, the porosity of the alloy is further reduced to about 0.09% with unobvious change of columnar grains. The average size of γ ’ phases is about(70±18) nm with the volume fraction of about(32±3.6)%. The results of room temperature tensile tests show that the additive manufactured γ’-strengthened CoNi-base superalloy exhibits excellent strength and ductility,showing a good potential of industrial application.更多还原