Development of Ni-based and CeO2-modified coatings by microwave heating

In the present investigation the microwave hybrid heating process was used to develop coatings on P20 tool steel substrates. The experiments were carried out in a domestic microwave oven of 900 W and 2.45 GHz frequency for a duration of 360 s. Ni-based clads/coatings without cerium oxide (CeO2; unmodified coating) and with the addition of CeO2 (modified coating) with varying wt.% of 1-3 were developed by the microwave hybrid heating process. The effect of CeO2 addition on the microstructure, X-ray diffraction, and Vickers hardness, and the abrasive wear behavior of the developed clads was studied under varying sliding speeds and grit sizes. Investigation showed that the optimal addition of CeO2 (1 wt.%) can effectively improve the microstructure, hardness, and abrasive wear behavior of the coatings. The Vicker's microhardness of the modified coating with 1 wt.% of CeO2 was 30% higher than the unmodified coating. Abrasive wear resistance of the modified coatings was found higher with an optimal addition of 1 wt.% CeO2 at varying sliding speeds and grit sizes.