Published online by Cambridge University Press: 26 February 2011
Targeting to develop E21 Co3AlC based heat resistant alloys, phase stability of E21 Co3AlC and (Co, Ni)3AlC has been investigated together with the magnetic properties of E21’ Co3AlC0.5 which is formed by the extra ordering of carbon atoms accompanying anti-phase boundary (APB). The correlation of ferromagnetism with APB in E21’ Co3AlC0.5 was evaluated using single crystals by high-resolution transmission electron microscopy (HRTEM) and vibrating sample magnetometer. Anti-phase domain (APD) size affects the ferromagnetism: for instance, the saturation magnetization becomes larger as the APD size is smaller. Local atomic configuration at APB was clearly observed by HRTEM image.