激光沉积修复TA15合金的组织和力学性能

Microstructure and mechanical properties of laser deposition repaired TA15 alloy

采用激光沉积修复方法对TA15槽损伤试样进行了修复试验,考察了修复试样的组织和力学特点,发现激光修复试样组织是由基材的双态组织经由热影响区过渡到修复区的网篮组织。修复区组织为粗大的原始柱状β晶,晶粒内为α/β网篮组织,晶内α片层取向随机,宽0.4～0.5μm。分析了修复区和坡面存在熔合不良缺陷的原因,并给出了纠正措施。修复试样的室温静拉伸结果表明,试样的抗拉强度接近工业锻件水平,表明修复区与基材之间形成了致密冶金结合,但由于修复区粗大柱状晶组织,试样的冲击韧性比基材稍差。

Researches on the laser deposition repairing of TA15 alloy forgings having groove damage were investigated, and the microstructure characteristic of laser deposition repairing component was analyzed. The repaired component experienced a con- tinuous microstructural transition from duplex microstructure with equiaxial α and lamellarα/β in the repaired substrate to the epi- taxial coarser columnar β with basket weave α/β through heat-affected zone. And the repaired zone was characterized by a fine α/β lamellar microstructure with various random orientations, and the a was 0.4-0.5 μm. It was found that large sloped angle could cause ill bonding along the groove side slope, and a corrective action was given to avoid this defects. The results of the repaired groove sample tensile test at room temperature show that tensile strength is approaching to the forged TA15 alloy, but its impact toughness is a little lower than that of the substrate for its coarser columnar β .