论文部分内容阅读
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℃/1.5h/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 laser ablation TA15 titanium alloy on the impact performance of different samples, TA15 titanium alloy was prepared by laser deposition technology and the microstructure, microhardness and impact properties of the sample were studied. The experimental results show that the macrostructure of the laser-deposited sample is coarse β-columnar crystals which are vertical and penetrate through a plurality of sedimentary layers. The β-columnar crystal is a typical networked near-α-titanium alloy structure. After annealed at 850 ° C / 1.5h / AC The morphology of elongated needle-like morphology was significantly reduced with α-mass fraction and the aspect ratio became larger. After double annealing, the rod-like structure was nearly stable. The impact toughness of double annealing and deposition direction specimens was significantly higher than that of vertical deposition direction Value increased by about 25%), the impact value of laser deposition forming two sample directions are lower than the forging substrate. The impact fracture modes in the two directions are different, the semi-ductile fracture along the deposition direction is semi-ductile fracture, the brittle cleavage fracture along the vertical deposition direction and the ductile fracture at the base.