【作者】 杜晓东；

【导师】 丁厚福； 陈翌庆；

【作者基本信息】 合肥工业大学 ， 材料学， 2006， 博士

【摘要】 材料的磨损是机械产品中常见的失效形式，每年给社会带来巨大的经济损失。在冶金矿山行业湿式磨矿机中，耐磨材料不仅受到浆料的腐蚀，还受到物料的冲击和磨损，这三者的交互作用大大加速了耐磨材料的磨损，降低了材料的寿命。因此，研究开发新型的耐冲击腐蚀磨损材料，提高工件在冲击、腐蚀和磨损交互作用下的服役寿命具有现实意义。 新型耐磨材料的开发依赖于材料磨损特性和机制的研究。只有明确了不同条件下材料的磨损特性和磨损机制，才能针对实际情况合理选择耐磨材料、制定正确的工艺过程，以及指导设计开发新型耐磨材料。而材料性能、寿命的好坏取决于其合金设计和工艺设计的优劣。 本文采用MLDF-10冲击腐蚀磨损试验机，研究了高锰钢、中碳低合金钢、CrNiMo、CrMnMo低碳高合金钢在冲击腐蚀磨损条件下的磨损特性、机制，探讨了冲击功、冲击角、腐蚀介质pH值对冲击腐蚀磨损特性和机制的影响；以光学金相分析、扫描电镜分析等研究方法为手段，研究了上述合金冲击腐蚀磨损机制形成的微观机理：并采用有限元分析方法，利用ANSYS软件，实现了在虚拟环境下对冲击过程的研究和数字仿真，研究了冲击磨料磨损冲击过程中试样的应力分布状态。 主要研究结果如下： (1) 强冲击弱腐蚀的冲击腐蚀磨损条件下，随冲击功的增加，高锰钢耐磨性明显下降；失效机制由挤出棱沿根断裂及轻微浅层剥落和腐蚀磨损，向浅层的疲劳剥落和严重腐蚀磨损及深层加工硬化导致的硬化层大块剥落和严重腐蚀磨损转变；在弱冲击强腐蚀的冲击腐蚀磨损条件下，随冲击功增加，其冲击腐蚀磨损机制由微观犁皱和二次显微切削变为以挤出棱的低周疲劳断裂为主，兼有轻微的腐蚀磨损。 (2) 在冲击腐蚀磨损条件下，冲击角减小，高锰钢冲击腐蚀磨损失效机制由浅层疲劳剥落和腐蚀磨损向深层剥落和严重腐蚀磨损转变；冲击腐蚀磨损特性曲线变得陡峭，稳定磨损期缩短；裂纹起源倾向于选择表面腐蚀坑底部应力集中区。 (3) 中碳低合金钢在冲击腐蚀磨损条件下，冲击功增加，失效机制由以浅层剥落为主向以深层剥落为主转变。其剥落裂纹均起源于表面，在亚表层中扩更多还原

【Abstract】 The wear of materials is the common failure form of mechanical productions. It results in tremendous economic losses around the world. The wear resistant materials used in the wet-grinding machine in metallurgical industry are corroded by the slurry, as well as impacted and abraded by the mineral particles. The interaction of these three factors accelerates the wear rate of the wear resistant materials and reduces the service life greatly. So, it is significant to develop the new impact-corrosion-wear resistant materials and increase the service life of the workpieces under the interaction of impact, corrosion and wear.The development of new wear resistant materials depends upon the investigation of the wear character and mechanism of the materials. The materials can be chosen properly, the processes can be determined correctly and the new wear resistant materials can be designed and developed only when the wear characteristic and mechanism of materials under various conditions are understood. The properties and service life of the materials depend on the alloy design and process design.The wear character and mechanism of high manganese steels, medium carbon low alloyed steels, CrNiMo and CrMnMo low carbon high alloy steels in the impact corrosion and wear condition were investigated by means of MLDF-10 impact corrosion and wear tester in the paper. The influence of impact energy, impact angle and pH value of corrodent on the character and the mechanism were evaluated. The optical metallographic analysis and SEM analysis were carried out to investigate the micro mechanism of impact corrosion and wear. The ANSYS finite element code was chosen to perform the simulation of the transient dynamic impact processes in the virtual environment, and evaluated the stress distribution in the impact corrosion and wear process.The main results are shown as follows.(1) In the stronger impact and lower intensive corrosion condition, the wear更多还原