Abstract Ti10Fe5Si5Cr3Nb composite coatings were fabricated using laser cladding technique. Laser power was varied from 800W to 1200W while the scanning speed was kept constant at 1.5 m/min. The microstructural analysis of the samples was conducted by using optical microscope, X-ray diffractometer and scanning electron microscope coupled with energy dispersive spectroscopy. Potentiodynamic polarization and diamond indenter were used to study the corrosion and microhardness properties of the alloy. The alloy exhibited a dendritic microstructure with Si-rich dispersed phase. Grain coarsening was observed to be dependent on coating depth. The microhardness was high at the top and decreased with coating depth. No improvement in corrosion resistance was noticed but the presence of Cr in the alloy promoted passivation.

Cylindrical components of dimensions 15 mm in diameter and 11 mm in height were laser printed by additive manufacturing using a LENS!™ system. Process parameters used in layer by layer build-ups showed that energy densities in the range of 200 - 300 J/mm³ were sufficient to produce adequate builds with improved physical structures and mechanical properties of Ti-6Al-4V ELI alloy, and subsequently used to produce tensile specimen that showed encouraging yield and tensile strengths in excess of 900 MPa. An approach to estimating the achievable tensile properties is proposed and investigated against experimental results as a means of identifying parameters to be used in studies aimed at tailoring mechanical properties of materials.

A theoretical approach based on a numerical simulation using experimental data is proposed as a contribution to the study of laser-based additive manufacturing by direct energy deposition (DED). The aim is to simulate the stages of layer-by-layer build-ups by considering the induced generated liquid metal in a cylindrical geometry. For normal atmospheric conditions, a 3D model is developed using the finite volumes method to solve the governing equations of the occurring fluid flows and heat transfers. The model is based on the experimental work performed on the LENS system at the Council for Scientific and Industrial Research's (CSIR) National Laser Centre (NLC), where Ti-6Al-4V cylindrical coupons are laser printed and characterised.

'n Teoretiese benadering, gebaseer op 'n numeriese simulasie wat van eksperimentele data gebruik maak, is voorgestel as 'n toevoeging tot die studie van lasergebaseerde toevoegings-vervaardiging met direkte energie deponering. Die doel is om die verskillende stadiums van laag-vir-laag opbou te simuleer deur die geïnduseerde vloeibare metaal in 'n silindriese geometrie te oorweeg. Vir normale atmosferiese toestande is 'n driedimensionele model onwikkel om die beherende vergelykings van die vloei en hitteoordrag op te los met behulp van die eindige volumes metode. Die model is gebaseer op eksperimentele werk wat deur die LENS sisteem by die Wetenskaplike en Nywerheids-navorsingsraad (WNNR) se Nasionale Lasersentrum gedoen is. Silindriese Ti-6Al-4V koepons is lasergedruk en karakteriseer.