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用等离子体法制备的纳米晶体铁由ＸＲＤ和ＳＥＭ等方法测定其晶粒尺寸的平均值为８７ｎｍ．用绝热量热方法在７９～３７１Ｋ温区精确测定了其低温热容、测量结果比大晶粒Ｆｅ的热容值有明显的增强．在 ８０～３００Ｋ温区之间增强热容为８％～１４％．差示扫描量热（ＤＳＣ）在高温区的研究结果则表明，纳米晶体 Ｆｅ在４００～７００Ｋ温区有一个宽的放热峰，对应于非平衡晶格缺陷所引起的含释放．８５０Ｋ观察到一个放热峰，是纳米晶体铁从α相向α＋γ相转变所引起的．
The average particle size of nanocrystalline iron prepared by plasma method was 87 nm as determined by XRD and SEM. The heat capacity at low temperature of 79 ~ 371K was accurately measured by the adiabatic calorimetry method. The measurement results showed that the heat capacity of the large grain Fe was obviously enhanced. In the 80 ~ 300K temperature increase between the heat capacity of 8% to 14%. The results of differential scanning calorimetry (DSC) in the high temperature region show that the nanocrystalline Fe has a broad exothermic peak in the temperature range from 400K to 700K, which corresponds to the release due to unbalance lattice defects. 850K observed an exothermic peak, is the nanocrystalline iron from α phase α + γ phase caused by the transformation.