Al-Mg-Si系合金の研究 (第7報)
押出し加工材の押出し加工ならびにその後の溶体化処理条件と結晶粒粗大化の関係
1964 年 14 巻 3 号 p. 154-163
詳細
1964 年 14 巻 3 号 p. 154-163
Experiments were carried out to study the manufacturing condition of extruded products of Al-0.45% Mg-0.38% Si alloy, with which their mechanical properties and electrical conductivity should meet the requirements of the 2EC standard (Tensile strength_??_20.3kg/mm2. Electrical conductivity_??_55% IACS), also with the least occurrence of grain growth.
The findings are summed up as follows:
(i) An abnormal grain growth is not observed in as extruded state of Al-0.45% Mg-0.38% Si alloy which was extruded at the temperature of 410 to 530°C with the reduction of 87 to 98%.
(ii) Solution heat treatment at or less than 480°C showed no abnormal grain growth of the above mentinned extruded products, but a large amount of grain growth due to secondary recrystallization was observed around the surface of extruded products after the solution heat treatment at higher temperature.
(iii) Extruded products of this alloy has about 22kg/mm2 in tensile strength and 56% IACS in electrical conductivity after solution heat treatment at 480°C followed by the precipitaition at 175°C for 20hrs.
(iv) Therefore, to meet with the requirement of the 2EC standard also to prevent an abnormal grain growth, solution heat treatment at 480°C is recommended for Al-Mg-Si alloy electric conductor.
