UHMWPE/纳米SiO_2弹性复合材料的粒子流冲蚀特性研究

Erosion properties of UHMWPE/nano-SiO_2 composite materials

采用热压工艺制备了UHMWPE/纳米SiO2弹性复合材料,实验考察了弹性复合材料的冲蚀特性,分析了UHMWPE/SiO2纳米复合材料的冲蚀磨损机理。结果表明:纳米SiO2含量为10%左右时,弹性复合材料的抗冲蚀性能最好,射流冲击角在30°左右时,冲蚀率达到峰值;冲蚀率与射流速度呈指数变化关系,纳米SiO2含量为10%时,复合材料的冲蚀速度指数n为2.03;水流含沙浓度达到1.92 kg/m3以后,材料冲蚀率随含沙浓度的增长趋势开始变得平缓;冲蚀率随沙粒粒径的增大而增大;纳米SiO2含量为10%左右时,弹性复合材料的冲蚀率较纯UHMEPE降低了30%,只有45#钢的1/16。UHMWPE/纳米SiO2弹性合材料的冲蚀机理主要是犁削和唇片的断裂。

Nano-composites of UHMWPE/SiO2 were prepared by filling nano-scale SiO2 in UHMWPE(ultra-high molecular weight polyethylene).The effects of SiO2 contents,impact angle,sand concentration,impact velocity and particle size on the erosion property of UHMWPE/SiO2were studied by using the rotating disk erosion instrument.The erosion property of UHMWPE/ SiO2 was compared with that of the pure UHMWPE and 45# steel.With a scanning electronic microscope(SEM),The worn surface of UHMWPE composite was examed and the mechanism was discussed.It was found that when the content of SiO2 reached 10%,the erosion rate of composite reached the minimum;the erosion of composite increased with the impact angle at first,and then,it decreased;when the impact angle was 30°,the erosion rate reached the maximun;the erosion rate of composite increased with increase in sand content,however,when the sand content reached about 1.92kg/m3,the increase tendency became slow;the relationship between the impacting speed and the erosion rate was an index function;when the content of SiO2 reached 10%,the index of composites was 2.03;The erosion rate of composites increased with increase in the particle size;when the content of SiO2 reached 10%,compared with UHMWPE,the erosion rate of composite decreased by 30% and reached one sixteenth of 45# steel.Its important wear mechanism was ploughing-cutting and breaking of cutting scraps.