Fatigue properties of a titanium alloy (Ti-6Al-4V) fabricated via electron beam melting (EBM): Effects of internal defects and residual stress
Fatigue properties of a titanium alloy (Ti-6Al-4V) fabricated via electron beam melting (EBM): Effects of internal defects and residual stress
复制标题
DOI：
10.1016/j.ijfatigue.2016.04.022
复制
发表时间：
2017-01-01
影响因子：
6
通讯作者：
Quinn, Timothy
中科院分区：
文献类型：
--
作者：
Hrabe, Nikolas;Gnaupel-Herold, Thomas;Quinn, Timothy
需要清楚地了解采用电子束熔炼（EBM）制造的Ti-6Al-4V的疲劳性能，以确保医疗器械和航空航天行业关键应用的性能。在这项工作中，残余应力和内部缺陷（孔隙和空隙）的EBM Ti-6Al-4V材料的疲劳性能的影响，在建成，应力消除;和热等静压（HIP）条件进行了评估。传统的技术被用来测量化学成分和量化微观结构，中子散射被用来测量残余应力。后处理没有改变化学成分。与竣工状态相比，应力消除材料的微观结构没有变化，而HIP材料的微观结构更粗。在这三种情况下均未测得显著的残余应力。这表明构建平台和层预热导致足够的工艺温度以实现原位完全应力消除。在10（7）次循环时，测量的竣工和应力消除条件下的疲劳强度在统计学上相似，测量值为200-250 MPa。在10（7）次循环时，HIP条件下测得的疲劳强度显著更高，为550-600 MPa。疲劳极限的增加归因于内部孔隙率和空隙含量的减少。爱思唯尔有限公司出版
A clear understanding of the fatigue properties of Ti-6Al-4V manufactured with electron beam melting (EBM) is needed to ensure performance in critical applications in the medical device and aerospace industries. In this work, the effects of residual stress and internal defects (pores and voids) on fatigue properties of EBM Ti-6Al-4V material in as-built, stress-relieved; and hot isostatic pressed (HIPed) conditions were evaluated. Conventional techniques were used to measure the chemical composition and quantify microstructures, and neutron scattering was utilized to measure residual stresses. Post-processing did not alter chemical composition. Compared to the as-built condition, microstructure was unchanged for stress-relieved material and coarser for HIPed material. No significant residual stresses were measured for any of the three conditions. This indicates build platform and layer preheating lead to sufficient process temperatures to achieve full stress relief in-situ. The fatigue strengths at 10(7) cycles measured for the as-built and stress-relieved conditions were statistically similar and were measured to be 200-250 MPa. A significantly higher fatigue strength at 10(7) cycles of 550-600 MPa was measured for the HIPed condition. The increase in fatigue endurance limit was attributed to a reduction in internal porosity and void content. Published by Elsevier Ltd.