材料期刊网

用旋转圆盘实验机对6种奥氏体铁基合金的抗冲蚀性能与高铬铸铁和水轮机用不锈钢0Cr13Ni5Mo进行了对比研究, 通过冲蚀形貌扫描电镜观察、组织结构X射线衍射分析以及犁削抗力和局域弹性的模拟测定, 探索了硬度、犁削抗力、弹性性质和相变对抗冲蚀性能的影响. 结果表明, 冲蚀微观失效机制是泥沙犁削. 犁削抗力Wp和局域弹性he是不锈钢和Fe-Mn-Si-Cr形状记忆合金抗冲蚀性能的主要控制因素, 其冲蚀率Re与局域弹性he值和犁削抗力Wp值之间存在着相关性较高的量化表征关系式. 相变在抗冲蚀性能中作用取决于局域弹性he和犁削抗力Wp的综合效应. Fe-Mn-Si-Cr形状记忆合金0Mn25Cr7Si6Cu抗冲蚀性能因诱发的密排六方ε马氏体局域弹性he高而优于除高铬铸铁以外的所有其它实验材料.

Erosion resistance of 6 austenitic ferrous alloys has been investigated by comparison with a high chromium iron and 0Cr13Ni5Mo stainless steel used for hydraulic turbine using a rotating disc rig. Based on SEM observations of eroded surface and X-ray diffraction examinations of microstructure as well as simulative measurements of plough-cutting resistant capacity Wp and localized surface layer elasticity he for tested alloys, an attempt has been made to discuss the influence of hardness as well as the capacity Wp, the elasticity he and phase transformation on the resistance of the alloys. The results show micro-failure mechanism is plough-cutting of sand particles in the erosion process. The capacity Wp and the elasticity he are predominant factors characterizing the resistance of the stainless steels and Fe-Mn-Si-Cr shape memory alloys, and there exists a good quantitative formula indicating correlation of the elasticity he and the capacity Wp with their erosion rate Re. The role of phase transformation in the resistance depends on the synthetic effect of the capacity Wp and the elasticity he of induced martensite, and the resistance of 0Mn25Cr7Si6Cu Fe-Mn-Si-Cr shape memory alloy is better than that of the other tested alloys except the high chromium iron because the value of he of induced hexagonal closed-packed martensite is larger.