Effect of Si Content on the Creep Properties of Ti-6Al-4Fe-xSi Alloys

Abstract:

Effect of silicon content on the creep properties of Ti-6Al-4Fe-xSi was studied. Creep resistance of Ti-6Al-4Fe-xSi alloys was superior to that of Ti-6Al-4V. Ti-6Al-4Fe-0.5Si alloy exhibited the highest rupture strength and creep resistance among the Ti-6Al-4Fe-xSi alloys investigated. The minimum creep rate of the alloys decreased with increasing silicon content up to 0.5wt.% and then it increased again when the silicon content was higher than 0.5wt.%. TiFe precipitates were formed mainly at the β phase area of Ti-6Al-4Fe-xSi alloys by consuming titanium and iron in β phase, when the alloys were thermally exposed at 500 and 600°C during the creep test. During the creep test, microvoids were induced at the TiFe/α phase interfaces and the cracks were formed along the TiFe/α phase interfaces by the coalescence of the voids. Those cracks were finally connected each other through the α phase.

• Periodical: Key Engineering Materials (Volumes 261-263)
• Pages: 1141-1146
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.261-263.1141
• Online since: April 2004
• Authors: Jong Won Yoon, E.H. Kim, Hi Won Jeong, Yong Taek Hyun, Seung Eon Kim, Yont Tai Lee
• Keywords: Creep Properties, Precipitation, Si Content, Ti-6Al-4Fe-xSi Alloy

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