Microstructure and Shear Strength in Brazing Joint of Mo-Cu Composite with 304 Stainless Steel by Ni-Cr-P Filler Metal

High Temperature Materials and Processes

Zheng Deshuang¹  Li Yajiang¹  Wang Jiteng¹  Wang Juan¹ 

[1] Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Shandong, China;

关键词: mo-cu composite;    ni-cr-p filler metal;    vacuum brazing;    microstructure;    81.05.bx;   

DOI  :  10.1515/htmp-2014-0048

来源: DOAJ

【 摘 要 】

The brazing of Mo-Cu composite and 304 stainless steel was carried out in vacuum with Ni-Cr-P filler metal at 980 °C for 20 min. Microstructure in Mo-Cu/304 stainless steel joint was investigated by field-emission scanning electron microscope (FE-SEM) with energy dispersive spectrometer (EDS) and shear strength was measured by shearing test. The results indicate that shear strength of the Mo-Cu/304 stainless steel joint is about 155 MPa. There forms eutectic structure of γ-Ni solid solution with Ni3P in the braze seam. Ni-Cu(Mo) and Ni-Fe solid solution are at the interface beside Mo-Cu composite and 304 stainless steel, respectively. Shear fracture exhibits mixed ductile-brittle fracture feature with trans-granular fracture, ductile dimples and tearing edges. Fracture originates from the interface between brazing seam and Mo-Cu composite and it propagates to the braze seam due to the formation of brittle Ni5P2 and Cr3P precipitation.

【 授权许可】

Unknown