【摘要】 通过形貌观察和硬度测试研究了球磨纯铁中纳米铁素体的退火行为 观察到球磨制备的纳米铁素体具有相对较高的热稳定性 在高温退火的条件下，纳米铁素体区域内出现了一些具有不规则晶界结构的大晶粒． 分析表明，纳米铁素体的品粒长大是通过邻近晶粒的聚合而完成的 显微硬度测试表明，纳米铁素体的硬度随着退火温度的升高而降低．然而在相同的退火条件下、纳米铁素体区的硬度仍然明显高于加工硬化区的硬度，这主要是因为纳米铁素体区的晶粒尺寸比较小以及退火时晶粒长大速度相对缓慢所致．更多还原

【Abstract】 The annealing behavior of nanocrystalline ferrite in pure Fe(0.004%C) has been studied through morphology observation and microhardness measurements. A relatively high thermal stability of the nano-ferrite formed by ball milling was observed. The irregular grain boundaries of nano-ferrite annealed at high temperature were attributed to that the grain growth of nanocrystalline ferrite took place by coalescence of neighboring grains. Although the microhardness of nano-ferrite decreased with increasing annealing temperature, a much higher hardness than that of the recrystal- lized work-hardened structure was still maintained under the same annealing condition. This may be attributed to the smaller grain size in the prior nano-ferrite region.更多还原