UHMWPE/纳米SiO_2弹性复合材料的平面旋转绕流冲蚀磨损研究

Study on Plane Sweeping Flow Erosion Wear of UHMWPE/Nano-SiO_2 Elastic Composite Materials

以纳米SiO2作为填料制备UHMWPE/SiO2弹性复合材料,利用转盘式冲蚀磨损试验台,研究了纳米SiO2含量、绕流速度、绕流含沙浓度(质量浓度)和沙粒粒径对UHMWPE/SiO2复合材料平面绕流冲蚀磨损性能的影响;采用扫描电镜观察表面冲蚀形貌。结果表明:当SiO2含量为10%(质量分数)左右时,弹性复合材料的冲蚀率最小;冲蚀率随绕流含沙浓度的增大而增大,但当含沙浓度到达0.96kg/m3以后,冲蚀率增长的趋势开始变得平缓;绕流速度对冲蚀率的影响呈指数关系,SiO2含量为10%时,复合材料的冲蚀速度指数n为1.87;冲蚀率随沙粒粒径的增大而增大;复合材料的冲蚀率较纯UHMWPE的冲蚀率降低了30%,只有45钢的冲蚀率的1/16;复合材料冲蚀表面存在挤压、隆起和唇片断裂的现象。

Nanocomposites of UHMWPE/SiO2 were prepared by filling nano--SiO2 in UHMWPE （Ultra-high molecular weight polyethylene ）. The effects of SiO2 contents in composite, sand concentration,velocity of sweeping flow and particle size on the erosion property of UHMWPE/SiO2 were studied by using the rotating disk erosion instrument. The erosion property of UHMWPE/SiO2 was compared with the pure UHMWPE and 45 steel. The worn surface of UHMWPE composite was examined with the scanning electron microscope（SEM） and the wear mechanism was discussed. It is found that when the content of SiO2 reaches 10M ,the erosion rate of composite reaches the minimum; the erosion rate of composite increases with the increase of sand content, however, when the sand content reaches about 0.96kg/m^3 , the increase tend starts to become slow. The relationship between the impact speed and the erosion rate is a power function, when the content of SiO2 reaches 10%, the power of composites is 1.87; the erosion rate of composites increases with the increase of the particle size;when the content of SiO2 reaches 10% ,compared with UHMWPE,the erosion rate of composites decreases by 30% and reaches one of sixteen of 45 steel. The important wear mechanism of plane sweeping flow erosion is extyuding deformation and ploughing--cutting and fracture of lip tablets for UHMWPE/SiO2 elastic composite materials.