Thalavai Pandian Karthikeyan, Neikter Magnus, Bahbou Fouzi, Hansson Thomas, Pederson Robert
Department of Production Technology, University West, 461 86 Trollhattan, Sweden.
GE Additive, 435 33 Molnlycke, Sweden.
Materials (Basel). 2022 May 19;15(10):3624. doi: 10.3390/ma15103624.
Evaluation of the high-temperature tensile properties of Ti-6Al-4V manufactured by electron beam melting (EBM) and subjected to a low-temperature hot isostatic pressing (HIP) treatment (800 °C) was performed in this study. The high-temperature tensile properties of as-built and standard HIP-treated (920 °C) materials were studied for comparison. Metallurgical characterization of the as-built, HIP-treated materials was carried out to understand the effect of temperature on the microstructure. As the HIP treatments were performed below the β-transus temperature (995 °C for Ti-6Al-4V), no significant difference was observed in β grain width between the as-built and HIP-treated samples. The standard HIP-treated material measured about 1.4×-1.7× wider α laths than those in the modified HIP (low-temperature HIP)-treated and as-built samples. The standard HIP-treated material showed about a 10-14% lower yield strength than other tested materials. At 350 °C, the yield strength decreased to about 65% compared to the room-temperature strength for all tested specimens. An increase in ductility was observed at 150 °C compared to that at room temperature, but the values decreased between 150 and 350 °C because of the activation of different slip systems.
本研究对通过电子束熔炼（EBM）制造并经过低温热等静压（HIP）处理（800℃）的Ti-6Al-4V的高温拉伸性能进行了评估。为作比较，研究了成型态和标准HIP处理（920℃）材料的高温拉伸性能。对成型态、HIP处理后的材料进行了金相表征，以了解温度对微观结构的影响。由于HIP处理是在β转变温度（Ti-6Al-4V为995℃）以下进行的，成型态和HIP处理后的样品在β晶粒宽度上未观察到显著差异。标准HIP处理的材料测得的α板条比经过改进的HIP（低温HIP）处理的样品和成型态样品宽约1.4×-1.7×。标准HIP处理的材料的屈服强度比其他测试材料低约10-14%。在350℃时，所有测试试样的屈服强度与室温强度相比下降至约65%。与室温相比，在150℃时观察到延展性增加，但由于不同滑移系的激活，其值在150℃至350℃之间下降。
