EN
Thermal properties, microstructure and magnetic properties of Fe_{79}Zr_{9}B_{12}, Fe_{76}Zr_{9}B_{15}, Fe_{39.5}Co_{39.5}Zr_{9}B_{12} and Fe_{38}Co_{38}Zr_{9}B_{15} alloys were investigated by differential thermal analysis, X-ray diffraction and vibrating sample magnetometer. High Co addition has a significant impact on the properties of alloys. High Co addition increases the main crystallization peak temperature and the crystallization activation energy. Moreover, high Co addition changes the crystallization products and influences the crystallization processes of Fe_{79}Zr_{9}B_{12} and Fe_{76}Zr_{9}B_{15} alloys. The specific saturation magnetization (M_{s}) increases and coercivity (H_{c}) decreases by high Co additions.