铁锰系统由于 Krber 与 Oelsen 及三本木与大谷的研究,可视为理想溶液,即服从 Raoult定律。作者之一曾研究锰在铁液与银液间的分配比及碳对此项分配比的影响。因碳在银液中溶解度很小,故分配比的变化可视为碳对锰在铁液内活度的影响,从而可求得 Fe-Mn-C 熔液内锰的活度。但是当碳>42%时必须应用外插,从得到的数据看来(图1 Iron-manganese system As Krber and Oelsen and Sammu and Otani research, can be regarded as the ideal solution, that is, subject to Raoult’s law. One of the authors studied the distribution of manganese between liquid iron and silver liquor and the effect of carbon on the distribution ratio. Due to the small solubility of carbon in the silver solution, the change of the distribution ratio can be regarded as the effect of carbon on the activity of manganese in the molten iron, so that the activity of manganese in the Fe-Mn-C solution can be obtained. However, extrapolation must be applied when the carbon is> 42%, as the data show (Figure 1)