Blending of powders for in-Situ Alloying of Ti-6Al-4V laser powder bed fusion
| dc.contributor.advisor | Blaine, Deborah | en_ZA |
| dc.contributor.author | Parker, Benjamin Stuart | en_ZA |
| dc.contributor.other | Stellenbosch University. Faculty of Engineering. Dept. of Mechanical and Mechatronic Engineering. | en_ZA |
| dc.date.accessioned | 2021-03-05T14:10:53Z | |
| dc.date.accessioned | 2021-04-21T14:41:27Z | |
| dc.date.available | 2021-03-05T14:10:53Z | |
| dc.date.available | 2021-04-21T14:41:27Z | |
| dc.date.issued | 2021-03 | |
| dc.description | Thesis (MEng)--Stellenbosch University, 2021. | en_ZA |
| dc.description.abstract | ENGLISH ABSTRACT: Novel powder blending techniques for Ti-6Al-4V powder mixtures, using master-alloy (MA) and blended elemental (BE) powders as opposed to the industry standard of pre-alloyed (PA) Ti-6Al-4V powder,have been developed for laser powder bed fusion(LPBF), in particular direct metal laser sintering ®(DMLS®).The quality of a LPBF component is a result of both the metal powder characteristics and the LPBF process parameters. This study is limited to the metal powder characterisation of such blends, focussing on typical powder characterisation metrics of morphology, particle size distribution(PSD), flowability, apparent and skeletal density, and the angle of repose(AoR). A relatively novel metric of spreadability is a key focus in this study as it directly represents the mechanics of the LPBF recoating process. A spreadability test rig was commissioned in this work and obtained spreadability metrics of percent coverage and spread density.Moisture accumulation on stored metal powders has an adverse effect on flowability and spreadability of metal powders and was shown to significantly improve through air drying.It was found that MA or BE powder blends have spreadability characteristics similar to PATi-6Al-4V,with the standard metrics of particle morphology,PSD, flowability, and AoR having the most significant correlation to spreadability.This indicates that powders that: are more spherical, have a narrow PSD span, are highly flowable, and have a low AoR, have a better spreadability. | en_ZA |
| dc.description.abstract | AFRIKAANSE OPSOMMING: Nuwe poeiermengingstegnieke vir Ti-6Al-4V poeiermengsels, met behulp van meesterlegering (MA) en gemengde elementêre (BE) poeiers, in teenstelling met die industriestandaard van voorgelegeerde (PA)Ti-6Al-4V poeier, is ontwikkel vir laser poeier bed samesmelting (LPBF), in die besonder direkte metaal laser sintering® (DMLS®). Die kwaliteit van 'n LPBF-komponent is die gevolg van beide die metaalpoeier-eienskappe en die LPBF-prosesparameters. Hierdiestudie is beperk tot die metaalpoeierkarakterisering van sulke mengsels, wat fokus op tipiese poeierkarakteriseringsmetrieke van morfologie, partikelgrootteverdeling (PSD), vloeibaarheid, effektieween geraamtedigtheid, en die hoek van rus (AoR).'n Maatstaf van verspreidbaarheid, wat relatief nuut is,is 'n kernfokus in hierdie studie, aangesien dit die meganika van die LPBF-verspreidingsproses direk beïnvloed. 'nVerspreidbaarheidstoets is in hierdie werk in diens gestelen het verspreidingsstatistieke van persentasie verspreidingen verspreidingsdigtheid verkry. Vogakkumulasie op gestoorde metaalpoeiers het 'n nadelige uitwerking op die vloeibaarheid en verspreidbaarheid van metaalpoeiers, en dit blyk dat dit aansienlik verbeter deur lugdroging. Daar is gevind dat MA-of BE-poeiermengsels verspreidbaarheidseienskappe het soortgelyk aan PA Ti-6Al-4V, met die standaardmeters van partikel-morfologie, PSD, vloeibaarheid en AoR,wat die belangrikste korrelasie met verspreidbaarheid het. Dit dui daarop dat poeiers wat: meer sferiesis, 'n smal PSD-span het, baie vloeibaar is en 'n lae AoR het, 'n beter verspreidbaarheid het. | af_ZA |
| dc.description.version | Masters | en_ZA |
| dc.format.extent | 144 pages | en_ZA |
| dc.identifier.uri | http://hdl.handle.net/10019.1/110122 | |
| dc.language.iso | en_ZA | en_ZA |
| dc.publisher | Stellenbosch : Stellenbosch University | en_ZA |
| dc.rights.holder | Stellenbosch University | en_ZA |
| dc.subject | Additive manufacturing (AM) | en_ZA |
| dc.subject | Powder metallurgy | en_ZA |
| dc.subject | Laser Powder Bed Fusion (LPBF) | en_ZA |
| dc.subject | Spreadability | en_ZA |
| dc.subject | UCTD | en_ZA |
| dc.subject | Metal-metal bonds | en_ZA |
| dc.title | Blending of powders for in-Situ Alloying of Ti-6Al-4V laser powder bed fusion | en_ZA |
| dc.type | Thesis | en_ZA |