The effects of solder alloys on the morphologies and mechanical properties of brazed diamond grits

• The diamond grits are brazed with Ag–Cu–Ti alloy or Ni–Cr alloy.
• Ag–Cu–Ti alloy has little effect on the morphologies and mechanical properties.
• The morphologies of brazed diamond grits with Ni–Cr alloy have changed.
• The mechanical properties of brazed diamond grits with Ni–Cr alloy are decreased.

In this work, diamond grits are brazed with either Ag–Cu–Ti alloy or Ni–Cr alloy. Variations in the morphology of the brazed diamond grits, such as graphitization, erosion, microcracking and fracture, are observed. The compressive strength and thermal toughness index (TTI) of the brazed diamond grits are evaluated. The results obtained show that the morphologies of the original, unaltered diamond grits are similar to those of the brazed diamond grits. When the diamond grits were brazed using the Ag–Cu–Ti alloy, several disadvantageous phenomena, i.e., graphitization, erosion, microcracking, and fracture, were not observed, and the compressive strength and the TTI values of the brazed diamond grits were decreased only slightly. However, when the diamond grits were brazed with the Ni–Cr alloy, surface graphitization, erosion, microcracking, and fracture of the brazed diamond grits resulted, in addition to a significant reduction of the mechanical strength of the brazed diamond grits.