화학공학소재연구정보센터
Materials Science Forum, Vol.475-479, 2949-2954, 2005
Developing high strain rate superplasticity in aluminum alloys
The conventional materials used in superplastic forming operations generally have grain sizes of similar to 2 mu m or larger and they exhibit superplasticity at relatively low strain rates. Processing by equal-channel angular pressing (ECAP) produces materials having ultrafine-grain sizes, usually in the submicrometer range. If these ultrafine grains show reasonable stability at elevated temperatures, the alloys may exhibit a capability for achieving superplastic elongations at high strain rates. This paper examines the development of ultrafine-grained structures and superplastic ductilities in a spray-cast aluminum 7034 alloys through ECAP. The results show that ECAP is a very effective procedure for achieving grain refinement and superplasticity at rapid strain rates.