金属材料直流磁场干摩擦的研究进展

磁场干摩擦主要是研究磁场强度参量对材料干摩擦磨损性能的影响机理和规律。系统综述了金属材料直流磁场干摩擦的研究过程、研究方法和相应研究成果。阐述了不同磁属性(抗磁性、顺磁性和铁磁性)材料的磁场干摩擦特性及其机理,得出材料磁导率与其磁场干摩擦学特性有一定对应关系,材料磁导率越大,磨损率和摩擦系数的减小趋势越明显,并指出了试验研究中遇到的问题,如应关注摩擦副材料选配、磁场施加装置、摩擦接触方式及装卡装置等。为了避开材料化学成分不同造成的干扰,设计了三种制备方案,发现通过热处理工艺改变微观组织相含量或添加铁、钴、镍等铁磁性元素进行化学成分设计等常规的材料制备方法,难以达到目的。最终利用奥氏体不锈钢1Cr18Ni9Ti较大的冷加工硬化特性,采用常温下锻造工艺制备了不同磁导率的几种相同成分材料,使磁导率成为关键变量。研究了磁场强度、材料磁导率与其磁场干摩擦特性的交互影响情况和规律,并展望了未来需要开展的研究方向。

Dry Friction of Metal Materials under DC Magnetic Field

For dry friction in magnetic field, the work mainly aims to study mechanism and rule of effects of magnetic field intensity parameters on dry friction and wear properties of materials. Study process, study methods and corresponding study results regarding dry friction of metal materials in DC magnetic field were reviewed systematically. Dry friction properties and mechanism of different magnetic (diamagnetic, paramagnetic and ferromagnetic) materials in magnetic field were expounded. It was concluded that magnetic permeability of materials had certain corresponding relation with dry friction properties in dry friction. The higher the magnetic permeability was, the more obvious the decreasing trend of wear rate and wear coefficient were. Problems encountered during experimental study were pointed out, for example, friction pair material selection, magnetic field applying device, frictional contact mode and holding jig should be noted. Three preparation schemes were designed to prevent interference caused by difference in chemical composition. It was founded that the aim was hardly achieved in conventional material preparation methods by changing micro-structure phase content with heat treatment process, or changing chemical composition by adding ferromagnetic elements including Fe, Co and Ni. Finally, relying on extensive cold working hardening characteristics of austenitic stainless steel 1Cr18Ni9Ti, several materials with identical composition and of different magnetic permeability were prepared by adopting forging process at room temperature. As a result, magnetic permeability became a key variable. Reciprocal effect and effect law of magnetic field intensity and material magnetic permeability on dry friction properties in magnetic field were studied, and research orientation in the future was expected.