为了研究激光沉积TA15钛合金不同取样方向对冲击性能的影响, 采用激光沉积制造技术制备了TA15钛合金试样, 并对试样的显微组织、显微硬度、冲击性能等进行研究。实验结果表明, 激光沉积试样宏观组织为垂直并贯穿多个沉积层的粗大β柱状晶, β柱状晶内为典型的网篮状近α钛合金组织, 经850 ℃/1.5 h/AC退火后组织为细长针状形貌, α团束明显减少, 长宽比变大, 双重退火后为稳定近棒状网篮组织; 双重退火, 沉积方向试样的冲击韧性明显高于垂直沉积方向(冲击值提高约25％), 激光沉积成形两种取样方向试样的冲击值均低于锻造基材。两种方向上的冲击断裂方式不同, 沿沉积方向上断裂为半韧性半解理断裂, 沿垂直沉积方向上断裂为脆性解理断裂, 基材为韧性断裂。

In order to study the influence of different sampling directions on the impact properties of laser deposited TA15 Titanium alloy. TA15 Titanium alloy samples were fabricated by laser deposition manufacturing technique, and the microstructure, micro-hardness and impact properties of the samples were studied. The experimental results show that the macrostructure of sample by LDM consisted of coarse β columnar grains that are perpendicular and penetrate multiple deposited layers. β column crystal is a typical basket-like near α Titanium alloy. After 850 ℃/1.5 h/AC annealing, the microstructure was needle shape, the α group apparently decreased, length-width ratio increased and after double annealing, the microstructure was stable near rod shape basket organization. The impact toughness of the samples with different sampling direction were different, the impact toughness in the deposition direction was obviously higher than in the vertical deposition direction(impact value increased about 25％), and the impact values of the two samples were lower than that of the forged substrate. Two directions had different impact fracture modes, which were semi-cleavage-ductile fracture along the deposition direction and brittle fracture along the vertical deposition direction, and the damage of the substrate tended ductile fracture.