Wear behaviors of Cf/Mg composites fabricated by extrusion directly following vacuum pressure infiltration technique

• Published in: Wear Vol. 307; no. 1-2; pp. 127 - 133
• Main Authors: Qi, Lehua, Guan, Juntao, Liu, Jian, Zhou, Jiming, Wei, Xinliang
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 30-09-2013; Elsevier
• Subjects: Applied sciences; Contact of materials. Friction. Wear; Electron microscopy; Exact sciences and technology; Extrusion; Fiber orientation; Fibre reinforced metals; Infiltration; Magnesium; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metal-matrix composite; Metals. Metallurgy; Powder metallurgy. Composite materials; Production techniques; Sliding; Sliding wear; Surface analysis; Wear; Wear mechanisms; Wear rate; Wear testing; Metal-matrix composite; Sliding wear; Wear testing; Surface analysis; Electron microscopy; Scanning electron microscopy; Fibre reinforced metal; Metal matrix composite; Wear test; Wear mechanisms; Composite material; Magnesium base alloys; Matrix fiber interface; Wear rate; Extrusion; Infiltration; Fiber orientation; Delamination; Squeeze casting; Carbon fiber
• ISSN: 0043-1648; 1873-2577
• DOI: 10.1016/j.wear.2013.08.024

Cf/Mg composites were fabricated by extrusion directly following vacuum pressure infiltration technique (EVI). Fiber distribution and wear behaviors of the composites were investigated. For comparison, Cf/Mg composites were also fabricated by squeeze casting as references. Dry wear tests were carried out at room temperature under a normal load of 100N, at a sliding velocity of 0.47m/s for sliding distances up to 2000m. Worn surfaces were observed under SEM to understand wear mechanisms. The results indicated that wear rates of squeeze-casting composites were higher than those of as-extruded composites (fabricated by EVI). The main wear mechanisms of the squeeze-casting composite were delamination wear. Fiber orientation with respect to sliding direction had a remarkable influence on the wear rates. With fiber orientation paralleled to the sliding direction, the wear rate of composites was higher, compared with that when fiber orientation inclined to the sliding direction. Correspondingly, carbon fibers on the worn surface were pulled out and fractured, respectively. The main wear mechanisms of the as-extruded composites were abrasive wear and fiber fracture. In addition, partial delaminations were found on the worn surface, when fiber orientation was parallel to the sliding direction. With fiber orientation perpendicular to the sliding direction, the wear rate of composites was somewhat lower than that when fiber orientation was parallel to the sliding direction.
•Investigate wear behaviors of Cf/Mg composites fabricated by extrusion directly following vacuum pressure infiltration technique (EVI).•Fiber distributions, worn surfaces and sub-surfaces were observed by SEM.•Wear rates of Cf/Mg composites fabricated by EVI were lower than those by squeeze casting method.•Fiber orientation has no obvious influence on wear rate of the composite fabricated by EVI.•Wear mechanisms of the composites fabricated by EVI were abrasive wear and fiber breakage.