Heat treatment of TI-6AL-4V produced by laserCUSING

Date
2015
Journal Title
Journal ISSN
Volume Title
Publisher
SAIIE
Abstract
LaserCUSING® is a selective laser melting (SLM) process that is capable of manufacturing parts by melting powder with heat input from a laser beam. LaserCUSING demonstrates potential for producing the intricate geometries specifically required for biomedical implants and aerospace applications. One main limitation to this form of rapid prototyping is the lack of published studies on the material performance of the resulting material. Studies of the material’s performance are often complicated by dependence on several factors, including starting powder properties, laser parameters, and post-processing heat treatments. This study aims to investigate the mechanical properties of LaserCUSING-produced Ti-6Al-4V and its performance relative to the conventional wrought counterpart. A combination of conventional and LaserCUSING-tailored heat treatments is performed. The resulting microstructures are studied and linked to the properties obtained from hardness tests. The findings highlight that LaserCused Ti-6Al-4V is competitive with traditional materials, provided that optimal parameters are chosen and parts are subject to tailored post-processing. In the as-built condition, LaserCused Ti-6Al-4V displays superior strength and hardness as a result of a martensitic microstructure, and a poorer performance in ductility. However, the material performance can be improved using tailored heat treatments. Careful consideration must be given to suitable post-processing before application in critical components in the aerospace or biomedical industry can occur.
LaserCUSING® is ‘n selektiewe lasersmeltproses met die vermoë om onderdele te vervaardig deur die smelt van poeier met hitte inset van ‘n laserstraal. LaserCUSING toon die potensiaal om ingewikkelde geometrieë benodig vir biomediese implantate en lugvaart toepassings, te produseer. Een van die hoof beperkings tot hierdie vorm van blits prototipering is die tekort aan gepubliseerde studies oor die materiaaleienskappe van die gevolglike materiaal. Studies van die materiaaleienskappe is dikwels verder gekompliseer as gevolg van die invloed van verskeie faktore, soos die aanvanklike poeier eienskappe, die laser parameters en hittebehandelings na die lasersmeltproses. Hierdie studie beoog om die meganiese eienskappe van Ti-6Al-4V wat met LaserCUSING geproduseer is, en die vertoning daarvan relatief tot ‘n konvensionele bewerkte eweknie, te ondersoek. ‘n Kombinasie van konvensionele en aangepaste hittebehandelings is toegepas. Die resulterende mikro-strukture is ondersoek en verwantskappe tot die resultate van hardheidstoetse is gevind. Die resultate toon dat die Ti-6Al-4V met tradisionele materiale kan kompeteer mits optimale parameters vooraf gekies word en dat onderdele aangepaste hittebehandelings ondergaan. Die Ti-6Al-4V toon beter sterkte en hardheid, maar het swakker smeebaarheid. Noukeurige oorweging vir verwerking na die lasersmelt is nodig voor die toepassing daarvan op kritiese komponente.
Description
CITATION: Becker, T., Van Rooyen, M. & Dimitrov, D. 2015. Heat treatment of TI-6AL-4V produced by laserCUSING. South African Journal of Industrial Engineering, 26(2):93-103, doi:10.7166/26-2-1161.
The original publication is available at http://sajie.journals.ac.za
Keywords
Metals -- Heat treatment, Microstructure, Powder metallurgy
Citation
Becker, T., Van Rooyen, M. & Dimitrov, D. 2015. Heat treatment of TI-6AL-4V produced by laserCUSING. South African Journal of Industrial Engineering, 26(2):93-103, doi:10.7166/26-2-1161