Microstructure and dry sliding wear properties of laser clad tribaloy coatings

Crack-free laser clad layers of intermetallic Tribaloy^® T-800 (Deloro) were prepared on a substrate of Fe52. Key factor in eliminating the cracks in clad layer was proper preheating of substrate up to 460 – 500 °C. Cross-sections of T-800 coatings were examined to reveal the microstructure by using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction and microhardness testing methods. The sliding wear resistance was tested in dry condition at room temperature by using block-on-ring test device. Tribaloy T-800 coatings turned out to be more wear resistant than solid solution strengthened and carbide type hardfacing alloys. The wear mechanism was studied by examining worn surfaces with SEM. It was largely oxidative in nature for Tribaloys and adhesive for solid solution strengthened alloy.