Abstract:
Iron-coated zirconia toughened alumina (ZTA) particle reinforced high chromium cast iron composites were fabricated by the lost foam casting process. The effects of ZTA volume fraction (45%, 51%, 58%) on the microstructure and abrasive wear properties of the composites were investigated, and the wear mechanism was analyzed. The results show that when the ZTA content was 45% and 51%, there were no obvious defects such as gaps, debonding and delamination at the interface between the iron-coated ZTA particles and the matrix, and the interface bonding was good. When the ZTA content was 58%, gap defects appeared at the interface. Compared with high chromium cast iron, the wear mass loss of the composites with different ZTA contents was smaller, and the wear mass loss decreased first and then increased with the increase of ZTA content. When the ZTA content reached 51%, the wear mass loss was the lowest, only 40% of that of high chromium cast iron. During the wear process, the matrix was concave due to micro-cutting wear by hard abrasive, and the iron-coated ZTA particles protruded from the matrix surface. The excellent interface bonding performance between the particles and the matrix could effectively restrain the protruding particles from falling off, allowing them to stably play a protective role for the matrix, preventing the abrasive from embedding and cutting the matrix, thereby improving the wear resistance.