Effect of Aluminum Coating on Corrosion and Heat Transfer Performance of Magnetic Refrigerant Gadolinium

• Published in: Journal of Wuhan University of Technology. Materials science edition 2019-08, Vol.34 (4), p.914-918
• Main Authors: Guo, Huaqiang, Tang, Yongbai
• Format: Article
• Language: English
• Subjects: Aluminum; Aluminum coatings; Chemistry and Materials Science; Coating effects; Composite materials; Corrosion effects; Corrosion potential; Corrosion rate; Corrosion resistance; Diffusion coating; Diffusion coefficient; Gadolinium; Heat conductivity; Heat transfer; Materials Science; Metallic Materials; Pressure effects; Protective coatings; Thermal conductivity; Thermal diffusion; Thermal resistance; Workpieces
• ISSN: 1000-2413; 1993-0437
• DOI: 10.1007/s11595-019-2137-4

The surface of gadolinium was covered with a layer of Al film(10–15 µm) by hot-press. Corrosion resistance, thermal conductivity and diffusivity of the composites were studied. As a result, temperature and pressure are the main factors that influence the combination of Gd and Al, and the effect of pressure is especially obvious. When the pressure exceeds 700 MPa, the binding force reaches 9 MPa. After coating, corrosion resistance of the composites is significantly improved, Corrosion rate is significantly reduced and mass loss reduced to one-tenth of pure Gd after 15 days. The current density decreases by an order of magnitude and corrosion potential increases by 0.3 V. The thermal conductivity of the composites is 11.12 W·m −1 ·K −1 . Due to good thermal diffusion coefficient of aluminum, the magnetic work piece coated with Al film might show better heat transfer performance.