ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Microstructural evolution taking place during equal channel angular pressing (ECAP) wasstudied in a commercial coarse-grained Al-6%Mg-0.4%Mn-0.3%Sc alloy in a temperature interval 200-450oC (~0.5-0.8 Tm). Samples were pressed using route A to a total strain of 12 and quenched in waterafter each ECAP pass. Uniform fine-grained microstructures with the average grain sizes of 0.7 and 2.50m, are almost fully evolved at high ECAP strains at 250oC and 450oC, respectively, while ECAP at300oC (~0.6 Tm) leads to the formation of bimodal grain structure with fine grains of around 1 µm andrelatively coarse grains of around 8 µm. The latter are developed due to the occurrence of staticrecrystallization during “keeping” time in the ECAP channel and/or reheating between ECAP passes. Themicrostructural development under warm-to-hot ECAP conditions is discussed in terms of the largepotential for grain boundary migration resulted from an overlapping of accelerated grain boundarymobility at high pressing temperatures and enhanced driving force for recrystallization, which is caused bya strong inhibition of dynamic recovery in a heavily-alloyed Al alloy
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/19/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.584-586.481.pdf
