Microstructure and wear characteristics of ATZ ceramic particle reinforced gray iron matrix surface composites

The alumina toughened zirconia (ATZ) ceramic particle reinforced gray iron matrix surface composite was successfully manufactured by pressureless infiltration. The porous preform played a key role in the infiltrating progress. The microstructure was observed by scanning electron microscopy (SEM); the phase constitutions was analyzed by X-ray diffraction (XRD); and the hardness and wear resistance of selected specimens were tested by hardness testing machine and abrasion testing machine, respectively. The addition of high carbon ferrochromium powders leads to the formation of white iron during solidification. The wear volume loss rates of ATZ ceramic particle reinforced gray iron matrix surface composite decreases first, and then tends to be stable. The wear resistance of the composite is 2.7 times higher than that of gray iron matrix. The reason is a combination of the surface hardness increase of gray iron matrix and ATZ ceramic particles and alloy carbides protecting effect on gray iron matrix.