Infrared brazing Fe3Al using Ag-based filler metals
Journal
Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
Journal Volume
41
Journal Issue
11
Pages
2836-2843
Date Issued
2010
Author(s)
Shiue, R.-K.
Li, Y.
Wu, S.-K.
Wu, L.-M.
Shiue, Ren-Kae
Li, Yao
Wu, Shyi-Kaan
Wu, Ling-Mei
Abstract
The microstructural evolution and bonding shear strength of infrared brazed Fe3Al using Ag and BAg-8 (72Ag-28Cu in wt pct) braze alloys have been studied. The Ag-rich phase alloyed with Al dominates the entire Ag brazed joints, and the shear strength is independent of the brazing time. The BAg-8 brazed joint contains Ag-Cu eutectic for all brazing conditions, and its shear strength increases slightly with increasing brazing time. The highest shear strength of 181 MPa is acquired from the joint infrared brazed at 1073 K (800 °C) for 600 seconds. A thin layer of Fe3Al is identified at the interface between the brazed zone and the substrate for both braze alloys. An Al depletion zone in the Fe3Al substrate next to the interfacial Fe3Al is identified as the α-Fe phase. The dissolution of Al from the Fe3Al substrate into the molten braze causes the formation of α-Fe in the Fe3Al substrate. © 2010 The Minerals, Metals & Materials Society and ASM International.
Type
journal article