合金激光表面加工组织的超塑扩散连接特性

Through the combination of superplastic forming/diffusion bonding (SPF/DB) with laser surface processing, a new approach to join TiAl workpieces was developed. By optimizing the parameters of laser surface processing and post-heat treatment, good refined microstructure and sound surface roughness were obtained, which offer a good basis to SPF/DB. With this new process, SPF/DB at a lower temperature and in a shorter time than conventional SPF/DB was achieved. Simultaneously, This process, solving the contradiction between refined microstructure and high-temperature creep resistance, shows a good potential of application. In this project, the bonding mechanism of rapid solidification microstructure was discussed, the bonding effects brought by temperature, pressure and time and the effect of different temperatures on the rate of dendritic structure refinement were posted. A practical and theoretical basis of bonding of laser surface melted alloy was developed primarily. Additionally, this process offers a new idea for surface processing.

以激光表面改性技术和超塑扩散连接技术结合为基点，研究激光快速熔凝组织及经二次热处理组织在超塑扩散连接过程中的组织变化规律、作用机理以及连接规律，深化对快速熔凝非平衡组织超塑扩散连接规律及特性的认识，为开发低温、少时和高质量的新型高温结构材料超塑连接工艺提供理论依据，并为钛铝合金应用提供技术支持。