Fe-Cr-C纳米晶合金材料的制备成型与摩擦磨损性能研究

【作者】 刘胜林；

【导师】 耿刚强；

【作者基本信息】 长安大学 ， 材料学， 2004， 硕士

【摘要】 本文研究了Fe-Cr-C纳米晶合金材料在机械合金化(MA)制备和粉末真空热压烧结成型过程中，成分和工艺参数变化对材料的晶粒度、颗粒度、固态相变以及力学性能和摩擦磨损性能影响作用。试验结果显示：机械合金化可以加速固态扩散，随着球磨的进行，粉末晶粒、颗粒尺寸急剧下降，晶粒、颗粒尺寸最小分别可达70纳米与300纳米左右。根据相变特点将Fe-Cr-C三元合金的机械合金化过程分为两个阶段：物理粉碎阶段、扩散固溶阶段。此外，球磨粉末在400℃条件下进行真空热压烧结即可完全烧结成形。经优选出的最佳烧结工艺参数烧结的试样机械性能最好。其硬度值是T10钢的大约1.9倍，耐磨性能比T10钢大约高四倍多，而滑动磨擦系数仅为T10钢的0.70，并对烧结成型的后续工艺进行了探索，提出了改进意见。更多还原

【Abstract】 The ferrous-base nanocrystalline material synthesized by mechanical alloying (MA) and vacuum hot pressing was studied. The ternary Fe-Cr-C nanometer alloy powders were obtained in the planetary mill.Evaluating the transformations in solids, the affect of the element and the changing size of the grain and the granule and friction and wear properties.The results show that the MA can accelerate the diffusion in solids. During the MA process, the size of grain in the sample sharply decreases to about 300nm after 20 hour milling. According to the characters of transformations in solids, the MA process can be divided into two stages: physical fragmentizing stage, diffusion and solid solution stage. In addition, this paper also made a research on the milled powder forming technology, the bulk nanocrystalline samples were synthesized using vacuum hot pressing under all kind of the pressure and temperature and sintering time. Through mechanical test ,evaluated the affect of the element and temperature on mechanic performance of samples ,and presented some improvement methods.更多还原