Microstructure, mechanical and wear resistance properties of low-pressure cold-sprayed Al-7 Mg/Al2O3 and Al-10 Mg/Al2O3 composite coatings

Abstract

Aluminium alloy-based metal matrix composites have successfully provided effective wear resistance and repair solutions in the automotive and aerospace sectors; however, the design and manufacture of these alloys are still under development. In this study, the microstructure, mechanical properties and wear resistance of low-pressure cold-sprayed Al-7 Mg/Al2O3 and Al-10 Mg/Al2O3 composite coatings were investigated. The specific wear rates of the coatings were measured when testing them against alumina (Al2O3) counterbody, and the results showed that the cold-sprayed Al-10 Mg/Al2O3 composite coating showed less wear due to its superior hardness, lower porosity and shorter mean free path compared to the Al-7 Mg/Al2O3 composite coating. The microstructural analysis of the worn surfaces of the composite coatings revealed abrasive wear as the primary wear mechanism, and more damages were observed on Al-7 Mg/Al2O3 composite coatings. Most notably, Al2O3 particles were pulled out from the coating and were entrapped between the Al2O3 counterbody and the coating contact surfaces, resulting in a three-body abrasion mode.

Wear behavior and wear mechanism of iron foam reinforced SiCp/A359 interpenetrating phases composites at high temperature

“…13 Recently, investigators have recognized that the removal of particles or fibers can lead to a decrease in the wear resistance of typical discontinuous reinforced metal matrix composites. 14 The poor wettability of molten metal and ceramic particles makes it difficult to incorporate reinforcing ceramic particles into a molten matrix under elevated temperature. The ceramic particle reinforced composites are hampered to be utilized for their commercial applications.…”

Solid-State Additive Deposition of AA7075 on AZ31B Substrate: Heat Treatment to Improve the Corrosion Fatigue Resistance

“…Mg is one of the lightest metallic materials, the potential candidate for light-weighting. The resistance to wear and corrosion of Mg alloys should be improved to extend the application of Mg alloys for structural applications, and surface modification is one of them [1][2][3][4][5][6]. The typical surface modification processes [7][8][9][10] of the Mg alloys are conversion coating, laser processing, physical vapor deposition, micro-arc oxidation, and solid-state additive deposition, namely cold spray (CS) deposition, etc.…”