J Mater Sci Technol ›› 2007, Vol. 23 ›› Issue (02): 201-206.

• Research Articles • Previous Articles     Next Articles

Microstructure and Wear Behaviour of Laser-induced Thermite Reaction Al2O3 Ceramic Coating on AA7075 Aluminum Alloy

Kaijin HUANG, Xin LIN, Changsheng XIE, T.M.Yue   

  1. State Key Laboratory of Plastic Forming Simulation and Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, China...
  • Received:2006-01-04 Revised:2006-06-20 Online:2007-03-28 Published:2009-10-10
  • Contact: Kaijin HUANG

Abstract: The microstructure and wear behaviour of the thermite reaction coating produced by the hybrid laser cladding-remelting on AA7075 aluminum alloy for the systems of Al-CuO-SiO2, Al-Cr2O3-SiO2, Al-Fe2O3-SiO2, and Al-TiO2-SiO2 were studied. The results of the X-ray diffraction (XRD) analysis show that in all the four reaction coatings, α-Al2O3 and γ-Al2O3 phases were present at the top surface, together with various intermetallic phases, the corresponding reduced metal and Al phase in the fusion zone. Under the dry sliding condition, the wear resistance, in terms of weight loss, of the laser-clad specimens was considerably higher than that of the untreated specimen. The predominant wear mechanism of the former specimens was abrasive wear, while for the latter, it was the adhesive wear that prevailed.

Key words: Laser cladding, Thermite reaction, Aluminum alloy, Wear