Author:Van Rooyen, Corney; Burger, H; Theron, MarithaDate:Jun 2009Laser cladding crack repair of austenitic stainless steel vessels subjected to internal water pressure was evaluated. The purpose of this investigation was to develop process parameters for in-situ repair of through-wall cracks in components ...Read more
Author:Kumar, S; Pityana, Sisa LDate:Mar 2010Modification of Aluminium surface by injecting, dispersing and melting TiB2 powder with the help of a laser beam promises to enhance tribological properties of Aluminium. The present work consists of making single lines and various overlapping ...Read more
Author:Lengopeng, T; Botes, A; Popoola, APIDate:Nov 2014This paper evaluates the effect of process parameters (laser power and scanning velocity) on clad layer height, heat affected zone (HAZ) width, metallurgical bonding to base metal and Vickers microhardness profiles of clad layers of various ...Read more
Author:Phume, L; Pityana, Sisa L; Meacock, C; Popoola, APIDate:Dec 2012The objectives of this study were to investigate laser surface coating of Ti6Al4V with preplaced Hafnium powder, and to determine the influence of the energy density on the characteristics of bonding and the microstructure.Read more
Author:Baloyi, N; Tlotleng, Monnamme; Meacock, Christopher; Pityana, Sisa L; Majumdar, JDDate:Nov 2012Laser coating is an advanced coating technology for improving the surface properties of various components. These coatings are extremely dense, crack-free and have non-porous microstructures. Coatings archived by laser based coating technology ...Read morecb
Author:Baloyi, NM; Popoola, API; Pityana, Sisa LDate:May 2014Coating is a technology for improving the surface properties of components. Laser coating produces uniform composition with thickened layers that display a good metallurgical bond to the base material. These coatings are dense and crack-free, ...Read more
Author:Botha, L; Du Plessis, A; Uys, H; de Clercq, LDate:01 Sep 2010Coherent control of quantum dynamics in optical, molecular and biological systems is a rapidly advancing field with many possible applications. This field of study was originally motivated by the goal of steering photoreactions into specific ...Read more
Author:Popoola, API; Pityana, Sisa L; Popoola, OMDate:Oct 2011Poor corrosion performance of aluminium alloys in marine environment has been a subject of intensive research recently. Aluminium substrate was alloyed with a combination of two metallic powders (Cu + Mo) using an Nd: YAG solid state laser. ...Read more
Author:Esser, DDate:Oct 2012In this presentation the development path of new solid-state laser technology, which is taken from the underlying laser physics to challenging real world applications, is shown.Read more
Author:Van Rooyen, Corney; Theron, Maritha; Burger, HPDate:Sep 2011This presentation highlights the case for refurbishment/performance enhancement of industrial components in South Africa. There is potential to improve operational efficiency and reduce operating cost provided that techno-economically viable ...Read more
Author:Labuschagne, K; Pityana, Sisa LDate:Jul 2005In view of the importance of material degradation during laser irradiation, which can have deleterious effects on mechanical and chemical properties of a component, a study was initiated to determine a threshold at which damage takes place ...Read more
Author:Kumpaty, S; Coen, B; Coen, L; Tlotleng, Monnamme; Arthur, Nana KK; Pityana, Sisa LDate:Nov 2021Ti-6Al-4V is a common alloy known for its use in aerospace and/or biomedical applications. In this study, Mo has been employed to increase the biocompatibility of Ti-6Al-4V. Two samples of Ti-6Al-4V with layers of differing percentages of Mo ...Read more
Author:Mahamood, RM; Akinlabi, ET; Shukla, M; Pityana, Sisa LDate:Mar 2013The effect of laser power on the resulting microstructure and microhardness of laser metal deposited Ti6Al4V powder on Ti6Al4V substrate has been investigated. The tracks were deposited using 99.6 % pure Ti6Al4V powder of particle size ranging ...Read more
Author:Abdulrahman, KO; Akinlabi, ET; Mahamood, RM; Pityana, Sisa L; Tlotleng, MonnammeDate:2018Development of additive manufacturing (AM) from three dimensional printers with ability of producing parts having no need for tooling continue to wax stronger in the manufacturing field. Laser metal deposition, a technique in AM is usually ...Read more
Author:Motha, S; Lekoadi, Paul; Raji, SA; Skhosane, Basebakhe S; Pityana, Sisa L; Tlotleng, MonnammeDate:Jun 2022Titanium alloys have two primary phases (a + ß) that are attributed to the a-stabiliser (aluminium) and ß-stabiliser (niobium). The latter stabilisers shift a-phase to higher temperature while the former stabilisers shift the ß-phase to lower ...Read more
Author:Michaelis, MM; Forbes, ADate:Jul 2006Early proposals for laser propulsion were surveyed. Propulsion theory and laboratory momentum coupling experiments demonstrate how it is possible to choose the target material so as to optimize payload efficiency, with a possible order-of-magnitude ...Read more
Author:Forbes, PBCDate:2008Polycyclic aromatic hydrocarbons (PAHs) occur in oil, coal and tar deposits, and are produced as byproducts of fuel burning (whether fossil fuel or biomass). At elevated levels, these pollutants are of concern due to their potential ...Read more