STUDY OF INFLUENCE OF TEMPERATURE-TIME FACTORS ALUMINIUM ALLOY STUCTURE АД31 Al-Mg-Si SYSTEM
The results of the study of macro and microstructure, grain sizes and their dispersion, as well as the degree of transformation of α and β iron phases, in cylindrical blanks with diameter of 0.203 m and length of 6.4 m from aluminium alloy АД31 Al-Mg-Si system obtained according to the technology: Melting, semi-continuous casting, mechanical treatment, homogenization annealing at temperatures of 560, 570 and 590 оС with subsequent holding for 0.5 h and cooling together with furnace, fan, sprayer and in water. It has been found that the highest cooling rate and lowest average grain size and dispersion are observed downwards for media: water, sprayer, fan, oven. It has been found that high temperature annealing at a temperature of 590 ° C is more effective than annealing at temperatures of 560 and 570 ° C, which is due to a decrease in the number of iron phases with a simultaneous increase in the proportion of trans-formed inclusions.