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以化学水解法合成的β－ＦｅｏｏＨ纳米微粉（平均粒径在１２ｎｍ左右）为原料，分别在０．０～４．５ＣＰａ和２００～３５０℃的压力和温度范围进行冷压和热压处理。实验结果表明，冷压对β－ＦｅｏｏＨ纳米固体的结构没有明显影响，但却使它的热致相变（从β－ＦｅＯＯＨ相到α－Ｆｅ＿２Ｏ＿３相）温度从常压下的２０３．８℃提高到４．５ＧＰａ压力下的２７４℃，接近常规体相材料的相变温度。而在一定的热压条件处理下，首次发现了从β－ＦｅＯＯＨ相到α－ＦｅＯＯＨ相的结构转变，并在４．５ＧＰａ、２００℃的热压条件下得到了转变过程中的一个新的亚稳相。从压力和温度对纳米微粒的作用角度，对上述实验结果进行了讨论。
The β-FeooH nanosized powders synthesized by chemical hydrolysis (average particle size about 12nm) were used as raw materials, respectively, under the pressure and temperature range of 0.0 ~ 4.5CPa and 200 ~ 350 ℃. The experimental results show that cold pressing has no obvious effect on the structure of β-FeooH nanosolid, but its temperature-induced phase transformation from β-FeOOH phase to α-Fe_2O_3 phase increases from 203.8 ℃ under normal pressure To 274 ° C at 4.5 GPa pressure, approaching the phase change temperature of conventional bulk materials. Under certain hot-pressing conditions, the structural transition from β-FeOOH phase to α-FeOOH phase was first discovered and a new sub-phase of transformation was obtained under the hot pressing conditions of 4.5GPa and 200 ℃ Steady phase. From the pressure and temperature on the role of nanoparticles, the above experimental results are discussed.