Laser cladding composite coating on mild steel using Ni–Cr–Ti–B₄C powder

ABSTRACT

The composite coating was fabricated by laser cladding on Q235 mild steel. The cross-section morphology, microstructure, phase, micro-hardness and wear resistance of the coating were investigated by scanning electron microscope, energy dispersive spectrometry, X-ray diffraction, Vickers micro-hardness tester and dry sliding wear testing machine, respectively. Results showed that composite coating was gained without cracks and bonded with substrate excellently because of the prominent metallurgical bonding. The composite coating was made up of Ni₃Ti, Cr₂Ti, Ni–Cr–Fe, TiB₂ and TiC. Ceramic reinforcements existed in coating with eutectic and independent structures. The micro-hardness of coating was about 5 times the substrate. Compared with substrate, the coating showed superior wear resistance.

KEYWORDS:

• Composite coating
• Q235 mild steel
• laser cladding
• microstructure
• wear resistance

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study work was supported by the National Natural Science Foundation of China (51475232); Young Scientists Fund of the National Natural Science Foundation of China (51605473); Jiangsu Natural Science Foundation (SBK2016022015); Science and Technology Planning Project of Jiangsu Province of China (BE2015029).