针对Ti-6Al-4V合金在加工和服役过程中的损伤特点,对Ti-6Al-4V合金锻件的3种典型误加工缺陷——槽缺陷、面缺陷和体缺陷进行了激光快速修复研究。激光修复区与锻件基体形成致密冶金结合,Al、V合金元素由锻件基体到激光修复区均匀分布,无宏观偏析。激光修复区组织为粗大原始β晶粒内分布细长的α针及编织细密的α+β板条组织,呈现典型的魏氏结构,热影响区组织从锻件的等轴α+转变β组织逐步过渡到魏氏(α+β)组织。对预制有3种类型缺陷的激光修复试样进行室温静载拉伸试验和硬度测试,结果表明修复试样的拉伸性能达到锻件标准(HB5224-1982)。激光修复试样的硬度和强度高于锻件基体,而塑性则低于锻件基体。因此,激光修复区和锻件基体可看作是一种“强+弱”的组合,这与二者的显微组织是相对应的。 Aiming at the damage characteristics of Ti-6Al-4V alloy during processing and service, three kinds of typical machining defects of Ti-6Al-4V alloy forgings, such as groove defects, surface defects and body defects, were studied by laser rapid repair. The laser repair area forms a dense metallurgical bond with the forging matrix, and the Al and V alloying elements are evenly distributed from the forging substrate to the laser repair area without macroscopic segregation. The laser-repaired zone is characterized by elongated α-needle and braided fine α + β lath in the coarse primary β-grains, showing the typical Wiesmannian structure. The tissue in the heat-affected zone is transformed from the isometric α + Transition to Wei’s (α + β) organization. The laser-repaired specimens prefabricated with three types of defects were subjected to static load at room temperature for tensile test and hardness test. The results showed that the tensile properties of the repaired specimens reached the forging standard (HB5224-1982). The hardness and strength of the laser-repaired specimen are higher than that of the forging and the plasticity is lower than that of the forging. Therefore, the laser repair area and the forging matrix can be regarded as a “strong + weak” combination, which is corresponding to the microstructure of the two.