Moran Terrence P, Carrion Patricio E, Lee Seungjong, Shamsaei Nima, Phan Nam, Warner Derek H
Cornell Fracture Group, Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, USA.
National Center for Additive Manufacturing Excellence (NCAME), Auburn University, Auburn, AL 36849, USA.
Materials (Basel). 2022 Mar 10;15(6):2051. doi: 10.3390/ma15062051.
The efficacy of hot isostatic pressing (HIP) for enhancing fatigue performance is investigated for additively manufactured (AM) Ti-6Al-4V. The limitations of HIP are probed by varying the initial material state via the selection of AM system, powder chemical composition, and process parameters. We demonstrate that the fatigue performance of HIP'd AM Ti-6Al-4V depends on the as-built quality of the material. Differences in common material attributes, such as pre-HIP defect populations or post-HIP microstructure morphology, are shown to be insufficient to explain the observed discrepancies in performance. This implies that additional microstructure attributes or localized deviations from the expected structure control the failure of this material. Finally, HIP parameters outside ASTM recommendations were explored, where a reduced temperature and high-pressure treatment yielded significantly improved fatigue performance.
研究了热等静压（HIP）对增材制造（AM）Ti-6Al-4V疲劳性能的增强效果。通过选择增材制造系统、粉末化学成分和工艺参数来改变初始材料状态，探究热等静压的局限性。我们证明，经过热等静压处理的增材制造Ti-6Al-4V的疲劳性能取决于材料的原始制造质量。常见材料属性的差异，如热等静压前的缺陷数量或热等静压后的微观结构形态，不足以解释观察到的性能差异。这意味着额外的微观结构属性或与预期结构的局部偏差控制着这种材料的失效。最后，探索了超出美国材料与试验协会（ASTM）建议的热等静压参数，其中降低温度和高压处理显著提高了疲劳性能。
