Development of nano-structured Al2O3-TiB2-TiN coatings by combined SHS and laser surface alloying
Source: The International Journal of Advanced Manufacturing Technology, Volume 38, Numbers 9-10, September 2008 , pp. 938-943(6)
Abstract:A powder mixture of aluminium (Al), titania (TiO2) and hexa-boron nitride (h-BN) was laser-triggered to undergo SHS (self-propagating high temperature synthesis) and was subsequently laser alloyed onto a mild steel substrate surface. A nano-structured coating was formed with high microhardness (∼3000 HV0.05 at the cross-section and ∼2600 HV0.2 on the top surface). X-ray diffraction (XRD) identified the presence of aluminium oxide (Al2O3), titanium di-boride (TiB2), titanium nitride (TiN), iron (Fe) and its borides (FeB, Fe2B) in the coating. Scanning electron microscopy (SEM) and high resolution transmission electron microscopic (HRTEM) analysis of the coating revealed nano-fibrous titanium-rich reinforcements in a matrix of nano-crystalline alumina. The thickness of titanium di-boride nano-fibres was an order of magnitude higher than the size of nano-alumina crystallites.
Document Type: Research Article
Affiliations: 1: Department of Mechanical Engineering, IIT Kharagpur, 721302, Kharagpur, West Bengal, India 2: International Advanced Research Center for powder metallurgy and new materials (ARCI), Hyderabad, India 3: Department Metallurgical & Materials Engineering, IIT Kharagpur, 721302, Kharagpur, West Bengal, India 4: Department of Mechanical Engineering, IIT Kharagpur, 721302, Kharagpur, West Bengal, India, Email: firstname.lastname@example.org
Publication date: September 1, 2008