V-5Cr-5Ti alloys have been fabricated using a laser melting deposition(LMD)additive manufacturing process,showing precipitates aggregated near the grain/dendrite boundaries.Since the mechanical properties of vanadium ...V-5Cr-5Ti alloys have been fabricated using a laser melting deposition(LMD)additive manufacturing process,showing precipitates aggregated near the grain/dendrite boundaries.Since the mechanical properties of vanadium alloys considerably depend on the precipitates,solution and aging treatments have been applied to eliminating the aggregations of the precipitates.The results show that as the solution temperature increases from 800 to 1560℃,the densities and the lengths of the precipitates are reduced,while the widths of the precipitates are increased.When the solution temperature reaches 1560℃,most impurity elements diffuse into the matrix and form into a nearly uniform supersaturated solid solution.Aging treatments have been applied to the 1560℃solution treated samples.It shows that as the aging temperature increases from 800 to 1200℃,the precipitate length increases,and the shapes of precipitates change from near-spherical to lath-like.Compared to 800 and 1200℃,aging at 1000℃results in the highest precipitate density.Compared to the LMD and solution-treated samples,the aged samples have the highest micro-hardness,due to the precipitation strengthening.展开更多
基金Project(51871203)supported by the National Natural Science Foundation of ChinaProject(TZ2018006-0303-02)supported by the Science Challenge Project,ChinaProjects(2020ZDZX0017,2019YFG0217)supported by the Sichuan Science and Technology Program,China。
文摘V-5Cr-5Ti alloys have been fabricated using a laser melting deposition(LMD)additive manufacturing process,showing precipitates aggregated near the grain/dendrite boundaries.Since the mechanical properties of vanadium alloys considerably depend on the precipitates,solution and aging treatments have been applied to eliminating the aggregations of the precipitates.The results show that as the solution temperature increases from 800 to 1560℃,the densities and the lengths of the precipitates are reduced,while the widths of the precipitates are increased.When the solution temperature reaches 1560℃,most impurity elements diffuse into the matrix and form into a nearly uniform supersaturated solid solution.Aging treatments have been applied to the 1560℃solution treated samples.It shows that as the aging temperature increases from 800 to 1200℃,the precipitate length increases,and the shapes of precipitates change from near-spherical to lath-like.Compared to 800 and 1200℃,aging at 1000℃results in the highest precipitate density.Compared to the LMD and solution-treated samples,the aged samples have the highest micro-hardness,due to the precipitation strengthening.
