Study on microstructure and wear properties of different nickel base hardfacing alloys deposited on austenitic stainless steel

Results of studies carried out on the microstructure, hardness, and wear properties of three nickel base Ni–Cr–B–Si hardfacing alloys deposited on austenitic stainless steel by gas tungsten arc welding are presented here. Sliding wear resistance of the deposits is evaluated by ball-on-disc tribo-test followed by electron microscopy and Raman spectroscopy of the worn out surfaces.

It is found that dilution in the deposit by the substrate alters microstructure and hardness and brings down wear resistance. The effect of dilution on wear resistance is more for the alloy with the highest alloy content due to change in the volume fraction of precipitate caused by dilution. Oxides formed on the wear track are different for these alloys and friction coefficients of the deposits are influenced by these oxide layers.