热处理对点式锻压激光成形GH4169合金组织与力学性能的影响

Effect of Heat Treatment on Microstructures and Mechanical Properties of Point-mode Forging and Laser Forming GH4169 Alloy

研究简化热处理制度对点式锻压激光沉积(PF-LF)GH4169合金显微组织和力学性能的影响。将时效时间由原来的18 h减少为3 h,不仅大大节省了试验时间,而且在提升材料性能方面也起到了重要作用。结果表明,在1 010℃固溶时效后,合金中的Laves相出现大部分熔解,合金发生再结晶现象,再结晶晶粒细小且分布均匀,平均晶粒尺寸为6.8μm左右,实现了超细晶组织,合金的强度和塑性也远超锻件标准。1 050℃固溶时效时,再结晶完成,晶粒尺寸略有长大,约为15μm, Laves相基本完全固溶消失,与1 010℃热处理相比,合金的强度有所下降而塑性有所改善,均超过锻件标准。在1 010℃和1 050℃进行双固溶时效时发现,合金中出现了大量的退火孪晶组织,退火孪晶的产生对合金的强度和塑性均产生了影响,虽然合金的性能均超过锻件标准,但略低于单固溶时效状态下的合金性能。

The effect of simplified heat treatment regime on the microstructure and mechanical properties of point-forged laser-deposited(PF-LF) GH4169 alloy was investigated. The reduction of the aging time from 18 h to 3 h not only saved the test time significantly, but also played an important role in enhancing the material properties. Results show that after solid solution aging at 1 010 ℃, most of the Laves phase in the alloy is dissolved and the alloy recrystallizes. The recrystallized grains are small and uniformly distributed, and the average grain size is about 6.8 μm, realizing the ultra-fine crystal organization. Moreover, the strength and plasticity of the alloy also far exceed the standard of forgings. Laves phase basically disappears completely solid solution, compared with 1 010 ℃ heat treatment, the strength of the alloy has decreased and plasticity has improved, both exceed the forging standards. At 1 050 ℃ solid solution aging, recrystallization is completed. The grain size grows slightly, which is about 15 μm, and the Laves phase is almost completely dissolved. Compared with the heat treatment at 1 010 ℃, the strength of the alloy decreases and the plasticity improves, which all exceed the forging standard. When double solid solution aging was performed at 1 010 ℃ and 1 050 ℃, it was found that a large number of annealed twins appeared in the alloy, and the annealed twins had an effect on the strength and plasticity of the alloy. Although the properties of the alloy exceeded the forging standard, they were slightly lower than the properties of the alloy in the single solid solution aging condition.