Study On The Erosion Wear Resistance Of UHMWPE/SiO₂ Elastic Composites

Chinese river sand content and the percentage of rivers with sand are both on the top of the world.It is difficult technology problems for the running water with sand wear the channels' edge wall and cause erosion in water conservancy and water-electricity project.It is an important method to develop the the erosion resistant material to prolong the life span of hydraulic turbine transition part.In this paper,a kind of elastic Ultra-high Molecular Weight Polyethylene (UHMWPE)/nanometer SiO₂ composites is synthesized by sintering and pressing.The erosion wear of elastic composites is studied,comparing with pure UHMWPE and Carbon steel.The abrasion mechanism of elastic composites is discussed through analyzing the worn surface with a scanning electron microscope(SEM).Based on this foundation,this material has been applied to project experiment.In the study of the dry sliding wear properties of elastic composites,it is found that the particulates of nanometer SiO₂ can decrease the friction coefficient and improve the UHMEPE wear properties as compared with Pure UHMWPE material.When the content of SiO₂ is about 10%,the friction coefficient of elastic composites is minimal and the wear properties is maximal;There are a transient running-period in the course of friction.The friction coefficient of elastic composites increases with the load at first,and then it becomes stable.The abrasion rate increases with the load;The main abrasion mechanism of elastic composites is plough ditch and fatigue peeling.The shooting flow and sweeping flow erosion wear resistance of elastic composites are investigated.Experiment results show that the relationship between the impacting speed and the erosion rate is an exponential function.When the impact angle of shooting flow is about 30°,the erosion rate reaches the peak;however,when the sand content of shooting flow is bclow 1.92kg/m³ and the sweeping flow is below 0.96kg/m³,the erosion rate of elastic composites rises with the increase of the sand content,then the increase tends to become slow;The experiment of the two kinds of erosion wear show that the erosion resistance of elastic composites is maximum, when the content of SiO₂ is about 10%.The erosion wear resistance and application among elastic composites,pure UHMWPE and 45^# steel are studied.It is found that the erosion rate of elastic composites decreases by 30%,as compared with pure UHMWPE,and is only 1/14 of 45^# steel.The wear resistance plate of hydraulic turbine made from the composites prolongs life span about three times comparing with stainless steel parts in the same conditions.