Comparative study on effects of different coatings on biodegradable and wear properties of Mg-2Zn-1Gd-0.5Zr alloy

• Published in: Surface & coatings technology Vol. 352; pp. 273 - 284
• Main Authors: Chen, Junxiu, Lu, Sihan, Tan, Lili, Etim, Iniobong P., Yang, Ke
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 25.10.2018; Elsevier BV
• Subjects: Alloys; Biodegradability; Biodegradation; Ca-P coating; Coating effects; Comparative studies; Corrosion resistance; Corrosion resistant alloys; Degradation; Gadolinium; Magnesium base alloys; MAO coating; Mg alloy; Oxidation; Protective coatings; Sr-P coating; Wear resistance; Biodegradation; Wear resistance; Ca-P coating; Mg alloy; Sr-P coating; MAO coating
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2018.08.028

Coating is one of the effective methods to improve the corrosion resistance of the biodegradable Mg alloys. In this work, comparative study on the effects of micro-arc oxidation (MAO) coating, SrP coating and CaP coating on the biodegradable and wear properties of Mg-2Zn-1Gd-0.5Zr alloy were investigated. The results showed that the degradation deposition contained Gd on the surfaces of both MAO coating and SrP coating, which stabilized the coating, thereby increasing the degradation resistance of the alloy. The wear test showed that MAO coating and CaP coating exhibited good wear resistance. For a 5 N loading, the sliding distances of MAO coating, SrP coating and CaP coating were 2.24 m, 0.29 m and 9.00 m respectively, before the coatings were completely destroyed. This investigation revealed that the MAO coating exhibits the best degradation resistance and the CaP coating exhibits the best wear resistance. •(1) The degradation products contained Gd could increase the degradation resistance of the MAO and SrP coated alloys.•Gd2O3 in MAO coating could stabilize the coating and delay the degradation process.•The rod-like deposition could act as a barrier to improve the wear resistance of the CaP coated alloy.