陈兴东 1杨季坤 1刘亚兵 1孙浩 2陈斌 2付伟2
作者信息
- 1. 东方电气集团东方汽轮机有限公司,四川 德阳 618000||清洁高效透平动力装备全国重点试验室,四川 德阳 618000
- 2. 哈尔滨工业大学(威海)山东省特种焊接技术重点试验室,山东 威海 264209
- 折叠
摘要
Abstract
Brazing of dissimilar high-temperature alloys has always been a hot topic in the field of brazing.Taking Inconel 738Lc and Hastelloy X dissimilar high-temperature alloys as the research object,and using 0.3 mm/BNi-2 tape brazing filler,brazing experiments were conducted under vacuum condition of 1.3×10-3 Pa at different temperatures(1 060～1 140℃).The microstructure,element diffusion,and fracture morphology of the obtained brazing joints were systematically investi-gated.The results show that the typical interface microstructure of the joint is IN738Lc/γ-Ni+β1+Ni-boride+Cr-boride/γ-phase+(Ni,Cr)-B+(Cr,Ni,Fe,Mo)B/Hastelloy X.At 1 060℃,a Cr/Ni-rich boride phase is formed in the center of the brazing seam;when the temperature rises to 1 100℃,the boride phase dissolves completely,forming a uniform Ni(s,s)structure,and the average shear strength of the joint reaches its peak value of 227.62 MPa,which is 13.1%higher than that at 1 060℃,and the fracture mechanism is characterized by the cleavage fracture of the IN738Lc base material.Further in-creasing the temperature to 1 140℃,the diffusion depth of the B element in the HX grain boundary increases to 159.2 μm,inducing the precipitation of the brittle(Cr,Ni,Fe,Mo)B phase along the grain boundary,resulting in a decrease in strength to 189.27 MPa.Based on this,the optimal process parameters are determined to be 1 100℃/10 min,and the joint strength reaches 92%of the room temperature tensile strength of the IN738Lc base material(247 MPa),meeting the long-term ser-vice requirements of gas turbine honeycomb sealing components.关键词
Inconel 738Lc合金/Hastelloy X合金/异种材料连接/钎焊/力学性能Key words
Inconel 738Lc alloy/Hastelloy X alloy/dissimilar materials joining/brazing/mechanical properties分类
矿业与冶金
