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Prediction of Texture Evolution in Continuous Cast Aluminum Alloys T ongguang Zhai , University of Kentucky, DMR 0413724. Hot rolling of CC AA5052 Al alloy. texture evolution. evolution rates. : evolution rate M i0 / M f : initial/final volume fraction s.
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Prediction of Texture Evolutionin Continuous Cast Aluminum Alloys Tongguang Zhai, University of Kentucky, DMR 0413724 Hot rolling of CC AA5052 Al alloy texture evolution evolution rates :evolution rate Mi0 /Mf: initial/final volume fractions • Research and Education Highlights • The evolution of texture components was quantified during thermo-mechanical processing of continuous cast Al alloys (AA2037, AA3004, AA5052 and AA5083) using Johnson-Mehl-Avrami-Kolmogorov type equations. • The evolution rates of texture components were also quantified in these alloys during thermomechanical treatment. • P texture {011}<566> could also be formed without concurrent precipitation, with the assistance of precipitates formed during the prior annealing in these alloys. • Undergraduate students (Kristin Banik, Jyothi Venugopalan, and Joshua Stitzer) participated in this project. Texture Evolution and evolution Rates Texture evolution during both rolling and annealing was successfully quantifiedin CC Al alloys using Johnson-Mehl-Avrami-Kolmogorov (JMAK)-type of equations, fi : change rate of a texture component ki and ni: constants e: true strain e0: true strain when fi=0 The texture evolution rate of each texture component was quantified and used to explain the evolution texture during both rolling and annealing. The evolution rates are given by,
Prediction of Texture Evolutionin Continuous Cast Aluminum Alloys T. Zhai, University of Kentucky. Award Number: DMR 0413724 P P P P P P P P P P P P 20mm 20mm P Texture Formation without Concurrent Precipitation • It was believed that concurrent precipitation effect was responsible for the formation of P orientation {011}<566> in Al-Mn alloys. Thisstudyrevealed that a strong P texture could still be formed in a continuous cast Al-Mn-Mg alloy without occurrence of concurrent precipitation. • The P orientation formation was growth controlled, as indicated by the observation of the P oriented grains in the early stage of recrystallization. • The strong pinning effect fromthe fine particles formed during the prior heat treatment was likely to lead to the formation of the P texture. • Production of continuous cast Al alloy sheet consumes over 25% less energy than the Al sheet produced by the conventional ingot casting method. (b) (a) (a) EBSD orientation map (cube orientation as reference) of recrystallized grain structure, P orientated grains are highlighted. (b) EBSD orientation map of the grain structureafter early recrystallization. The P oriented grains are highlighted. (c) TEM: Strong pinning effect by the precipitates formed during the prior heat treatment. (c)