熔体浇注温度和板倾斜度对倾斜板制备A356铝合金的凝固和显微组织的影响.pdfVIP

Trans. Nonferrous Met. Soc. China 24(2014) 3465−3476 Influence of melt pouring temperature and plate inclination on solidification and microstructure of A356 aluminum alloy produced using oblique plate N. K. KUND Department of Mechanical Engineering, Indian Institute of Science, Bangalore 560012, India Received 18 December 2013; accepted 21 April 2014 Abstract: The preparation of semisolid slurry of A356 aluminum alloy using an oblique plate was investigated. A356 alloy melt undergoes partial solidification when it flows down on an oblique plate cooled from underneath by counter flowing water. It results in continuous formation of columnar dendrites on plate wall. Due to forced convection, these dendrites are sheared off into equiaxed/fragmented grains and then washed away continuously to produce semisolid slurry at plate exit. Melt pouring temperature provides required condition of solidification whereas plate inclination enables necessary shear for producing semisolid slurry of desired quality. Slurry obtained was solidified in metal mould to produce semisolid-cast billets of desired microstructure. Furthermore, semisolid-cast billets were heat treated to improve surface quality. Microstructures of both semisolid-cast and heat-treated billets were analyzed. Effects of melt pouring temperature and plate inclination on solidification and microstructure of billets produced using oblique plate were described. The investigations involved four different melt pouring temperatures (620, 625, 630 and 635 °C) associated with four different plate inclinations (30°, 45°, 60° and 75°). Melt pouring temperature of 625 °C with plate inclination of 60° shows fine and globu