摘要
本文在分离式Hopkinson压杆装置上系统地进行了动态压缩实验,研究了成形方向对选区激光熔化(SLM) Ti-Al-Si系合金在不同应变率压缩载荷下的动态力学性能和断裂行为的影响。动态压缩试验在样品上进行,样品的成形方向平行(0˚)、对角(45˚)、垂直(90˚)于压缩方向。讨论了合金的初始组织、动态压缩应力–应变响应、冲击吸收功、应变率硬化效应和断裂行为。结果表明:3种取向的样品均具有明显的应变率敏感性,0˚样品具有较好的屈服强度,90˚样品具有较好的冲击吸收功;0˚样品在低于45˚、90˚样品的应变率下发生断裂,三种取向的样品的断口形貌都具有韧性韧窝和光滑表面,表明样品同时存在韧性断裂和脆性断裂。
In this paper, dynamic compression experiments were carried out systematically on a split Hopkinson pressure bar device to investigate the effect of forming direction on the dynamic mechanical properties and fracture behavior of selective laser melting (SLM) Ti-Al-Si alloy under compression loading at different strain rates. Dynamic compression experiments were carried out on samples with forming directions parallel (0˚), diagonal (45˚) and vertical (90˚) to the loading direction. The initial microstructure, dynamic compressive stress-strain response, impact absorption energy, strain rate hardening effect and fracture behavior of the alloy are discussed. The results show that the samples of three orientations have obvious strain rate sensitivity, 0˚ sample has better yield strength, and 90˚ sample has better impact absorption energy. The samples with 0˚ fracture occurred at strain rates lower than 45˚ and 90˚. The fracture morphology of the samples with three orientations showed ductile dimples and smooth surfaces, indicating that both ductile fracture and brittle fracture existed in the samples.
出处
《材料科学》
2024年第3期328-339,共12页
Material Sciences
