Regular Article

Effect of brazing temperatures on microstructure and properties of TC4/Ti₅₇Zr₁₃Cu₂₁Ni₉/316L

¹ School of New Energy and Materials, Southwest Petroleum University, Chengdu 610500, China
2 State Key Laboratory of Long-life High Temperature Materials, Dong Fang Turbine Co, Ltd., Deyang Sichuan 61800, China

^* e-mail: 380056676@qq.com

Received: 9 October 2021
Accepted: 6 December 2021

Abstract

Titanium alloy is an important metal material with excellent specific strength, which is widely used in aerospace field, nuclear industry, chemical medicine, and military industry. In order to investigate the connection conditions of TC4 titanium alloy and 316L stainless steel at different temperatures, the braze welding measurement with Ti₅₇Zr₁₃Cu₂₁Ni₉ filler metal was conducted in vacuum. The microstructure, morphology and phase of the joint were characterized by SEM (scanning electron microscope), EDS (Energy Dispersive Spectrometer) and XRD (X-ray diffraction), respectively. Microhardness and shear strength of the joint at room temperature and the bonding mechanism of TC4 and 316L were also investigated. The obtained results revealed that the main phases in the diffusion layer were Ti-based solid solution and Ti-Fe (TiFe and TiFe₂) intermetallic compoundsands (IMCs) the center of the braze was mainly composed of Ti-Fe IMCs, (Ti, Zr)₂(Ni, Cu), Ti-based solid solution. Additionally, the increase of brazing temperature firstly increased and then decreased the average shear strength with the maximum value of 133.9 MPa at 960 °C.