Carbide Cutting Tool Coatings Characterization of 8YSZ

Abstract

Using a duplex deposition of TiO2/8YSZ on a carbide cutting tool, a successful sol-gel procedure was achieved, resulting in high homogeneity, good dispersion, and a low average value of surface roughness (223.6)nm. Thermal experiments were done to see how well the coating layers could withstand heat transfer and thermal deterioration. Residual stresses for coated and uncoated carbide cutting tools are measured after thermal shock (thermal shock). Both were immediately chilled in ice water after being heated for 90 minutes for coated inserts and 30 minutes for uncoated inserts at 500, 600, 700, 800, 900, and 1200 °C. For inserts, thermal shock from 900 °C results in significantly different damage mechanisms. The uncoated outside surface is still delineated by a crack network and is surrounded by nearby homogenous cells, but the coated insert (sol gel TBC) in this case really has a few tiny cracks beginning at the edge. The coated insert (sol-gel TBC) fails after being heated to 1200 °C and then cooled in water to freezing which is caused the start of the duplex coating degradation .