Effect of Mo on corrosion resistance and magnetic property of LaFe_11.5Si_1.5 magnetic refrigeration materials

• Main Authors: HU Jie, DONG Zhong-qi, SHEN Ying-ming, WANG Yang, YANG Jun-ya
• Format: Article
• Language: zho
• Published: Journal of Materials Engineering 2020-08-01
• Series: Journal of Materials Engineering
• Subjects: magnetic refrigeration material; la(fe,si)₁₃; corrosion resistance; magnetic property
• Online Access: http://jme.biam.ac.cn/CN/Y2020/V48/I8/119

The effect of Mo on phase formation, corrosion resistance and magnetic property of LaFe_11.5Si_1.5 magnetic refrigeration materials were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), electrochemical workstation and vibrating sample magnetometer (VSM). The results show that the amount of α-Fe phase and La-rich phase increases with the increase of Mo content. Mo is distributed in both NaZn₁₃-type structure phase (1:13 phase for short) and α-Fe phase, but it does not appear in the La-rich phase. The studies on the corrosion resistance show that the corrosion potential increases and corrosion current density decreases with the increase of Mo content from <i>x</i>=0 to <i>x</i>=0.2, which indicate that the thermodynamic stability and corrosion resistance are improved. However, the corrosion resistance decreases while <i>x</i> increases to 0.3. The maximum magnetic entropy changes of LaFe_{11.5-<i>x</i>}Mo_<i>x</i>Si_1.5 under a magnetic field change of 0-3 T are about 18.51 J/(kg&#183;K)(<i>x</i>=0),16.24 J/(kg&#183;K)(<i>x</i>=0.1) and 5.68 J/(kg&#183;K)(<i>x</i>=0.2), respectively.