Microstructure and interfacial evaluation of Co-based alloy coating on copper by pulsed Nd:YAG multilayer laser cladding

• Published in: Journal of alloys and compounds Vol. 505; no. 2; pp. 645 - 653
• Main Authors: Yan, Hua, Wang, Aihua, Xu, Kaidong, Wang, Wenyan, Huang, Zaowen
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 03.09.2010; Elsevier
• Subjects: CLADDING; Co-based alloy; COATING; COATINGS; Cobalt; COBALT ALLOYS (50 TO 99 CO); Cobalt base alloys; Condensed matter: structure, mechanical and thermal properties; Copper; COPPER ALLOYS (40 TO 99.3 CU); Copper base alloys; Exact sciences and technology; Interface; INTERFACES; INTERLAYERS; Laser beam cladding; Laser cladding; Mechanical and acoustical properties; Mechanical and acoustical properties of condensed matter; Mechanical properties of solids; MICROSTRUCTURES; Multilayer; Multilayers; Nickel; Physical properties of thin films, nonelectronic; Physics; SCANNING ELECTRON MICROSCOPY; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Transport properties of condensed matter (nonelectronic); Tribology and hardness; Co-based alloy; Microstructures; Multilayer; Laser cladding; Interface; XRD; Coatings; Multilayers; Wear resistance; Copper; Diffusion; Scanning electron microscopy; Sliding wear; YAG laser; Mechanical properties; Dispersive spectrometry; Microhardness; Interfaces; Cobalt base alloys; Experimental result; Transmission electron microscopy; Solid solutions; Nickel; Microstructure; Tribology
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2010.06.099

Laser cladding defect-free coatings on copper is rather difficult. The purpose of this study is to fabricate high quality Co-based alloy coating on copper substrate by laser cladding. Powder preplacement with a thickness of 0.7 mm improves the absorptivity of copper substrate to laser effectively and generates defect-free coating. Microstructures, phase constitutions and wear properties are investigated by means of scanning electronic microscopy (SEM) with X-ray energy dispersive microanalysis (EDX), transmission electron microscopy (TEM) and X-ray diffraction (XRD), as well as dry sliding wear test. Experimental results show that α-Co solution, Cr 23C 6, Ni 17W 3 and Cr 4Ni 15W are the main phases in the Co-based coating. The Ni-based solid solutions (α-Co, Ni) and (Ni, Cu) are formed at interface, which generate metallurgical bonding by diffusion between Co-based coating and copper substrate. The average microhardness of the coating is 478HV 0.1. Wear resistance of copper is significantly improved by laser cladding Co-based alloy multilayer coating.