Al_2O_3基陶瓷拉丝模材料的摩擦磨损性能

FRICTION AND WEAR BEHAVIORS OF Al_2O_3-BASED CERAMIC COMPOSITE USING AS WIRE DRAWING DIES

采用热压法制备出三种Al2O3基复合陶瓷材料,用于陶瓷拉丝模的制作。计算出拉丝模在拉拔加工中的应力分布,指出拉丝模应力最大和磨损最严重的区域。陶瓷拉丝模的摩擦磨损特性是影响拉丝模工作寿命的主要原因,因此在MRH-3高速环块磨损试验机上对Al2O3基复合陶瓷材料摩擦磨损行为及其磨损机理作了试验研究。测试出Al2O3基复合陶瓷材料在不同转速和载荷下,摩擦因数和磨损率的变化规律。通过扫描电镜观测其磨损区微观形貌,分析其滑动摩擦的微观机理为机械磨损耕犁、粘着和脆性微脱落。结果表明,这三种Al2O3基复合陶瓷拉丝模材料具有较高抗弯强度和断裂韧度。Al2O3基复合陶瓷材料的磨损机理主要是脆性脱落和耕犁,具有良好的耐磨性,是制备拉丝模的优良材料。

Al2O3-based ceramic composite is produced using hot pressing sintering, it can be used to manufacture wire drawing dies. Work out the stress distributing of wire drawing dies at drawing process and point out the maximum region and the most wear and tear region. The friction and wear behaviors of the composite are the mostly influenced with the wire drawing dies working life. Therefore friction and wear behaviors of the composite are studied at high speed wear and tear test machine. Test and work out the coefficient of friction and the wear rate of Al2O3-based ceramic composite at the different rotate speed and the different load, point out the change trend of it. Observation the Al2O3-based ceramic composite microcosmic shape used by scanning electronic microscopy micrographics, the wear mechanism of the Al2O3-based ceramic composite is furrow, adhere and brittleness break off. Results show that the Al2O3-based ceramic composite has strong fracture toughness and wear resistance. The wear mechanism of Al2O3-based ceramic composite are mostly brittleness break off and furrow, it has great capabilities in wear resistance, and it is a preferable materials for wire drawing dies.