Tlotleng M., Akinlabi E., Shukla M., Pityana S.
Laser Material Processing, National Laser Center CSIR, Pretoria, South Africa; Department of Mechanical Engineering Science, University of Johannesburg, Auckland Park, Kingsway Campus, Johannesburg, South Africa; Department of Mechanical Engineering, MNNIT, Allahabad, UP, India; Department of Mechanical Engineering Technology, University of Johannesburg, Doornfontein Campus, Johannesburg, South Africa; Department of Chemical and Metallurgical Engineering, Tshwane University of Technology, Pretoria, South Africa
Tlotleng, M., Laser Material Processing, National Laser Center CSIR, Pretoria, South Africa, Department of Mechanical Engineering Science, University of Johannesburg, Auckland Park, Kingsway Campus, Johannesburg, South Africa; Akinlabi, E., Department of Mechanical Engineering Science, University of Johannesburg, Auckland Park, Kingsway Campus, Johannesburg, South Africa; Shukla, M., Department of Mechanical Engineering, MNNIT, Allahabad, UP, India, Department of Mechanical Engineering Technology, University of Johannesburg, Doornfontein Campus, Johannesburg, South Africa; Pityana, S., Laser Material Processing, National Laser Center CSIR, Pretoria, South Africa, Department of Chemical and Metallurgical Engineering, Tshwane University of Technology, Pretoria, South Africa
Bio-composite coatings of 20 wt.%, HAP and 80 wt.%, HAP were synthesized on Ti-6Al-4V substrates using LACS technique. The coatings were produced with a laser power of 2.5 kW, powder-laser spot trailing by 5 s. The coatings were analyzed for the microstructures, microhardness, composition, and bio-corrosion using SEM-EDS, XRD, hardness tester, and Metrohm PGSTAT101 machine. SEM images indicated least pores and crack-free coating with dark-spots of Ti-HAP for the 20 wt.%, HAP as opposed to the 80 wt.%, HAP coating which was solid, porous and finely cracked and had semi-melted Ti-HAP particles. The EDS mappings showed high content of HAP for the 80 wt.%, HAP coating. The diffraction patterns were similar, even though the Ti-HAP peak was broader in the 80 wt.%, HAP coating and the HAP intensities were lower for this coating except for the (004) peak. The hardness values taken at the interface inferred that the 80 wt.%, HAP coating was least bonded. It was possible to conclude that when this phase material increased the hardness dropped considerably. The bio-corrosion tests indicated that the presence of HAP in coating leads to a kinetically active coating as opposed to pure titanium coating. © 2014, ASM International.
Ceramic coatings; Composite coatings; Composite materials; Corrosion; Cracks; Hardness; Hydroxyapatite; Medical applications; Powder coatings; Sprayed coatings; Titanium; Active coatings; Biomedical applications; Crack-free coatings; Laser power; Laser-assisted cold sprays; Mechanical evaluation; Micro-structural; Phase materials; Aluminum coatings