2219铝合金构筑成形工艺实验与界面愈合规律

Additive forming process experiment and interface healing law for 2219 aluminum alloy

针对大型铝合金锻件组织性能调控难题,提出小尺寸坯料单元以在真空扩散预连接后进行热变形并保温的构筑成形方法制备大型铝合金锻件。通过对2219铝合金材料进行构筑成形工艺实验,研究不同变形量与压后保温时间对构筑界面愈合的影响,其中变形温度为460℃,变形量为10%、30%和50%,保温时间为0~4 h。结果表明:随着变形量由10%提升至50%,构筑界面由细长的缝隙演变为细小的孔洞,并最终实现完全愈合;在压后保温处理过程中,界面处氧元素存在由界面向基体处扩散的行为;其力学性能也随着变形量和压后保温时间的增加逐渐提高,并可达到与基体材料力学性能相当的水平。

For the problem of regulating the microstructure and properties of large aluminum alloy forgings,an additive forming method was proposed to form large aluminum alloy forgings by thermal deformation and thermal preservation after vacuum diffusion pre-connection of small-size blank units,and the influences of different deformation amounts and holding times after pressing on the interface healing were studied by additive forming process experiments of 2219 aluminum alloy material with the deformation temperature of 460℃,the deformation amounts of 10%,30%and 50%,and the holding time of 0-4 h.The results show that with the increasing of deformation amount from 10%to 50%,the interface changes from a narrow gap to a small hole and finally achieves healing completely,and the oxygen element at the interface diffuses from the interface to the base material in the process of heat holding after pressing.In addition,its mechanical properties also gradually increase with the increasing of deformation amount and holding time,and finally reach a level equivalent to the mechanical properties of base material.