A Modified Micro-Scale Abrasion for Large Hard Phase Cermet
Various research programmes have been conducted examining cermet coatings in relation to wear, corrosion and the combination of both (erosion-corrosion and abrasion-corrosion). Several methods have been employed to deposit cermet coatings, the most common being thermal spraying or hard facing (weld overlaying).The cermet coatings are carbide-sized ranging from 50 150 μm which is larger than abrasive particles which range between 2 to 10 μm. This allows the abrasive particles to interact with the carbide and matrix separately. Understanding the mechanism of this situation is necessary as abrasion maybe caused by a small abrasive. However, carbide sinking caused by this large carbide leads to diverse local carbide distributions and wear rates with a larger standard deviation. Modified micro-scale abrasion tests were performed with a silica abrasive of 2-10 μm particle size distribution and suspended in water. Due to the sinking of carbide particles during the coating process, the ground samples with more carbide on the surface displayed better wear resistance than those with a lower local carbide content. By using a modified micro-scale abrasion wear test, the correlation between local carbide content and wear rate may be determined with a smaller standard deviation. Rolling wear mode was observed due to the lower degree of hardness of the abrasive compared to the hard phase. The wear behaviour is related to the microstructure.
Wahyu Kuntjoro, Aidah Jumahat, Farrahshaida Mohd Salleh and Rosnadiah Bahsan
Z. Kamdi et al., "A Modified Micro-Scale Abrasion for Large Hard Phase Cermet", Applied Mechanics and Materials, Vol. 393, pp. 888-892, 2013