Motha, SLekoadi, PaulRaji, SASkhosane, Basebakhe SPityana, Sisa LTlotleng, Monnamme2023-04-062023-04-062022-06Motha, S., Lekoadi, P., Raji, S., Skhosane, B.S., Pityana, S.L. & Tlotleng, M. 2022. Laser micro in situ alloying of c-Ti46.8Al1Cr0.2Si with Manganese. <i>Materials Today: Proceedings,62, Supplement 1.</i> http://hdl.handle.net/10204/127252214-7853https://doi.org/10.1016/j.matpr.2022.05.077http://hdl.handle.net/10204/12725Titanium 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 temperatures. To extend their scope of application, (a + ß)-phase titanium alloys can be micro-alloyed with ß-eutetic elements (Mn, Cr, Si, Co etc) to form intermetallic compounds which are typically referred to as titanium aluminides (Ti-Al). Several intermetallic alloys can be formed in the Ti-Al phase diagram but only (a2)-Ti3Al and ( )-TiAl are stable and of relevance to structural engineering since they can be used in industries spanning across energy, aerospace and tissue-engineering. In this study, a castable -Ti46.8Al1Cr0.2Si pre-alloyed powder, was micro-alloyed with Mn in order to examine if it can improve its tensile properties. When 1–2 at. % Mn is added to Ti-Al alloys, it is able to increase ductility, reduce oxidation resistance and shift the (a2 + )/ to the titanium side and decrease the Al content in the -phase. To effectively ascertain these effects Mn feed rates were varied from 0.2 to 1.0 rpm during the micro-alloying of -Ti46.8Al1Cr0.2Si through in-situ laser deposition to form -Ti46.8Al1Cr0.2Si-(xMn). The produced clads were characterised for chemistry and microstructure using scanning electron microscope. Results concluded that Al content decrease with an increase in Mn from 56 at. % to 49 at. %. Mn of 10.16 g/min had similar properties to the non-Mn alloyed sample. Moreover, it was shown in this work that laser processing decreased the tensile and yield strength of the alloy when compared to the as-cast in previous studies, and that 2.69 g/min and 10.16 g/min are lower and upper Mn values when ductility of the master alloy is to be improved.FulltextenAdditive manufacturingAluminium(a2)-Ti3Al(c)-TiAl(a2+c) - duplex microstructureLaser In Situ AlloyingManganeseArticleMotha, S., Lekoadi, P., Raji, S., Skhosane, B. S., Pityana, S. L., & Tlotleng, M. (2022). Laser micro in situ alloying of c-Ti46.8Al1Cr0.2Si with Manganese. <i>Materials Today: Proceedings,62, Supplement 1</i>, http://hdl.handle.net/10204/12725Motha, S, Paul Lekoadi, SA Raji, Basebakhe S Skhosane, Sisa L Pityana, and Monnamme Tlotleng "Laser micro in situ alloying of c-Ti46.8Al1Cr0.2Si with Manganese." <i>Materials Today: Proceedings,62, Supplement 1</i> (2022) http://hdl.handle.net/10204/12725Motha S, Lekoadi P, Raji S, Skhosane BS, Pityana SL, Tlotleng M. Laser micro in situ alloying of c-Ti46.8Al1Cr0.2Si with Manganese. Materials Today: Proceedings,62, Supplement 1. 2022; http://hdl.handle.net/10204/12725.TY - Article AU - Motha, S AU - Lekoadi, Paul AU - Raji, SA AU - Skhosane, Basebakhe S AU - Pityana, Sisa L AU - Tlotleng, Monnamme AB - Titanium 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 temperatures. To extend their scope of application, (a + ß)-phase titanium alloys can be micro-alloyed with ß-eutetic elements (Mn, Cr, Si, Co etc) to form intermetallic compounds which are typically referred to as titanium aluminides (Ti-Al). Several intermetallic alloys can be formed in the Ti-Al phase diagram but only (a2)-Ti3Al and ( )-TiAl are stable and of relevance to structural engineering since they can be used in industries spanning across energy, aerospace and tissue-engineering. In this study, a castable -Ti46.8Al1Cr0.2Si pre-alloyed powder, was micro-alloyed with Mn in order to examine if it can improve its tensile properties. When 1–2 at. % Mn is added to Ti-Al alloys, it is able to increase ductility, reduce oxidation resistance and shift the (a2 + )/ to the titanium side and decrease the Al content in the -phase. To effectively ascertain these effects Mn feed rates were varied from 0.2 to 1.0 rpm during the micro-alloying of -Ti46.8Al1Cr0.2Si through in-situ laser deposition to form -Ti46.8Al1Cr0.2Si-(xMn). The produced clads were characterised for chemistry and microstructure using scanning electron microscope. Results concluded that Al content decrease with an increase in Mn from 56 at. % to 49 at. %. Mn of 10.16 g/min had similar properties to the non-Mn alloyed sample. Moreover, it was shown in this work that laser processing decreased the tensile and yield strength of the alloy when compared to the as-cast in previous studies, and that 2.69 g/min and 10.16 g/min are lower and upper Mn values when ductility of the master alloy is to be improved. DA - 2022-06 DB - ResearchSpace DP - CSIR J1 - Materials Today: Proceedings,62, Supplement 1 KW - Additive manufacturing KW - Aluminium KW - (a2)-Ti3Al KW - (c)-TiAl KW - (a2+c) - duplex microstructure KW - Laser In Situ Alloying KW - Manganese LK - https://researchspace.csir.co.za PY - 2022 SM - 2214-7853 T1 - Laser micro in situ alloying of c-Ti46.8Al1Cr0.2Si with Manganese TI - Laser micro in situ alloying of c-Ti46.8Al1Cr0.2Si with Manganese UR - http://hdl.handle.net/10204/12725 ER -26251