Thermal expansion behavior and mechanical properties of zirconia toughened alumina reinforced high chromium cast iron matrix composites
Abstract
A method based on squeeze casting technology, without the requirement of pre-coating for the particles and the usage of preforms beforehand, was proposed for the preparation of particle-reinforced metal matrix composites. A zirconia toughened alumina (ZTA) particles reinforced high chromium cast iron (HCCI) matrix composites were fabricated using this method. The microstructure, thermal expansion behavior, and properties including hardness, Young’s modulus, and strain recovery of the prepared composites were investigated by means of SEM, XRD, thermal mechanical analyzer, and nanoindentation tests. The results illustrate that the particles are relatively uniform distributed within the matrix and a mechanically strong bonding interface is obtained. The experimentally determined average coefficient of thermal expansion (CTE) of the composites is 12.77×10−6 K−1, which is in good agreement with theoretically calculated values, showing an error of less than 2%. The hardness and Young’s modulus of the ZTA are higher than that of the interface and matrix, and the elastic and plastic behavior of the interface is close to that of the ZTA particles.