High vacuum brazing of synthetic diamond grits with steel using micro/nano Al^sub 2^O^sub 3^ reinforced Ag-Cu-Ti alloy

• Published in: Journal of materials processing technology Vol. 266; p. 198
• Main Authors: Mukhopadhyay, Prithviraj, Ghosh, Amitava
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier BV 01-04-2019
• Subjects: Abrasion resistant alloys; Abrasion resistant steels; Aluminum oxide; Brazing alloys; Copper; Copper base alloys; Diamonds; Filler materials; High vacuum; Medium carbon steels; Microstructure; Silver base alloys; Vacuum brazing; Weight; Wetting
• ISSN: 0924-0136; 1873-4774
• DOI: 10.1016/j.jmatprotec.2018.11.002

Ti activated 72Ag-28Cu filler alloy was reinforced with micro/nano-Al2O3 ceramic particles for active brazing of synthetic diamond grits with 1045 steel. Microstructural changes due to reinforcement and corresponding influence on abrasion resistance characteristics of the modified filler alloy were observed. Different weight percentages (wt%), each of micro and nano-Al2O3 reinforcements, were tried. Micro-Al2O3 ceramic reinforcements were found to be uniformly distributed in the microstructure of the modified filler material. Alumina particles reacted with titanium to form hard Cu3Ti3O and TiO reaction compounds. Nano-Al2O3 reinforcements showed a tendency to get clustered, impairing the improvement in abrasion resistance property of the primary filler alloy. 1 wt% micro-Al2O3 added filler alloy underwent 58% less volumetric wear than the primary Ag-Cu-Ti alloy during the pin-on-disc test. This micro- reinforced filler also could effectively braze diamond grits with the steel without any significant deterioration in its wetting ability on diamond surface and joint strength, compared to its counterpart having the primary formulation.