3004系合金における高温加熱時の相変化
1983 年 33 巻 3 号 p. 149-156
詳細
1983 年 33 巻 3 号 p. 149-156
The structural changes in 3004 base alloys with commercial composition and higher Si or Mg content have been investigated by mainly optical microscopic observation and X-ray diffraction method. Heating led to the transformation of the coarse primary phase Al6 (Fe, Mn) into the equlibrium phase α-Al12 (Fe, Mn)3Si; so-called α transformation. TTT diagrams showed the C-curves having a nose near at 550°C. The activation energy for α transformation was estimated to be about 2.6eV. It suggests that the rate controlling process of α transformation is the diffusion of Mn atoms in Al matrix. In higher Si containing alloy, α transformation was accelerated, while, in higher Mg containing alloy, it was remarkably suppressed. The above results can be attributed to the differense of effective Si content for α transformation.
