The interfacial reaction between diamond grit and Ni-based brazing filler metal

Abstract

The main goal of this study was to examine the interfacial reaction between diamond grits and Ni-based brazing filler metal. A Ni alloy (Ni-7Cr-3Fe-3B-4Si (wt. %)) was used as the brazing filler metal. Brazing was carried out by heating up to the brazing temperature (1223, 1273 or 1323 K) and then held at this temperature for 10 min. The morphology of the interface between diamond grits and Ni-based filler metal exhibited a very good condition after this heat treatment. Cr-carbide and Ni-rich compounds were detected by XRD analysis in the vicinity of the interface between diamond grits and Ni-based filler metal after vacuum induction brazing. Chromium carbide is considered to play an important role in the high bonding strength achieved between diamonds grits and the brazing alloy. © 2007 The Japan Institute of Metals.