摘要
以TA15钛合金粉末为原料,利用激光沉积制造方法制备TA15钛合金拉伸试样厚壁件。通过光学显微镜(OM)、扫描电子显微镜(SEM)和X射线衍射(XRD)等方法研究退火温度及沉积方向对TA15钛合金组织、拉伸性能的影响,以及α相变形机制。结果表明:随着退火温度升高,显微组织中α相长宽比呈上升趋势;激光沉积成形TA15钛合金厚壁件在沉积和垂直沉积方向上的力学性能存在差异,沉积方向上的抗拉强度明显均低于垂直沉积方向上的抗拉强度;柱状晶晶界对α片层的受力变形有一定的阻碍作用;α片层通过挤压变形和滑移变形两种机制发生变形或断裂;2种方向上拉伸断裂方式不同,沿沉积方向上断裂为韧性断裂,沿垂直沉积方向上断裂为半解理半韧性断裂。
TA15 titanium alloy bulk specimens were prepared by laser deposition. The effect of annealing treatment and deposition direction on the microstructure characteristics, the tensile properties and alpha phase deformation mechanism has been studied by OM, SEM and XRD. The results show that the aspect ratio of alpha phase rises with the increase of annealing temperature. The mechanical properties in the deposition direction are different from those in the vertical deposition direction. The tensile strength in the deposition direction is obviously lower than that in the vertical direction. Columnar grain boundary hinders alpha lamellar distortion. Alpha lamellar along the deposition direction deforms or fractures by extrusion and slippage. Different directions have their unique tensile fracture modes, which are ductile fracture along the deposition direction and semi-cleavage-ductile fracture along the vertical deposition direction.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2016年第12期3295-3301,共7页
Rare Metal Materials and Engineering
基金
国家自然科学基金(51505301
51305280
51375316)
辽宁省自然科学基金(2015020118)
关键词
激光沉积制造
TA15钛合金
退火温度
显微组织
各向异性
laser deposition manufacturing
TA15 titanium alloy
annealing temperature
microstructure
anisotropy
