Title: Study on dry sliding wear characteristics of air plasma spraying deposited CoNiCrAlY intermetallic coatings on aluminium alloy substrate
Authors: Dipak Kumara; K.N. Pandey
Addresses: Department of Mechanical Engineering, Motilal Nehru National Institute of Technology (MNNIT) Allahabad, Allahabad-211004, UP, India ' Department of Mechanical Engineering, Motilal Nehru National Institute of Technology (MNNIT) Allahabad, Allahabad-211004, UP, India
Abstract: This study focuses on the wear and microstructural properties of CoNiCrAlY bond coatings produced on an aluminium alloy substrate by the air plasma spray (APS) technique. A wear test was performed on the samples to know the wear characteristics of APS CoNiCrAlY coatings. The microstructures of as-sprayed and worn bond coatings are presented by scanning electron microscopy and X-ray diffractometer respectively. Plastic smearing and tearing via ploughing, grooving and cracking modes were observed on wear track of CoNiCrAlY coatings using a pin-on-disk friction wear tester. Plastic smears and tearing were observed along the sliding direction of loadings. Microstructural study revealed that the plastic flow induced under sliding normal load conditions did not result in any changes in phase transformations and crystal structures. The wear rate of CoNiCrAlY coatings was also found to decrease with an increasing sliding distance.
Keywords: dry sliding wear; surface topography; intermetallics; thermal spray coatings; air plasma spraying; APS; intermetallic coatings; aluminium alloys; alloy substrates; microstructure; plastic smearing; tearing; ploughing; grooving; cracking; plastic flow; phase transformations; crystal structures.
International Journal of Surface Science and Engineering, 2016 Vol.10 No.3, pp.303 - 316
Received: 18 Sep 2014
Accepted: 15 May 2015
Published online: 17 Jun 2016 *