Wear Resistance of Iron-Coated Zirconia Toughened Alumina Particle Reinforced High Chromium Cast Iron Composites

Iron powder and zirconia oxide-strengthened alumina （ZTA） particles was used as raw materials to prepare iron-coated ZTA particle preforms with the same size and ZTA volume fractions of 45%, 51% and 58%. Then, the particle reinforced high chromium cast iron composites were fabricated using the lost foam casting process. The influence of ZTA volume fraction on the microstructure and abrasive wear performance of the composite materials was studied, and the wear mechanism was analyzed. The results show that when the ZTA volume fraction was 45% and 51%, there were no obvious defects such as gaps, debonding and delamination at the interface between the ZTA particles and the matrix, and the interface bonding was good. When the ZTA volume fraction 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 volume fraction was 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 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.