Research On The Evaluation Of Anti-scuffing Property Of Material On Piston Pump Friction Pair

In the development of hydraulic pump,plunger pump is fit to the development of rapidness,high pressure miniaturization and high effect of volumetric pump.The anti-scuffing property of three key friction pair material is the fundamental guarantee for the superiority of plunger pump,it is also one of the important blocks for the development of hydraulic pump.For this reason,the research of anti-scuffing performance of friction material,which provides some theoretical guidance for the selection of friction materials,is also very important.In this dissertation,the spheroidal graphite iron QT700-2 and aluminum bronze QAl9-4,which are used as the key friction pair of plunger pump,respectively match with GCr15 bearing steel.By comparative analysis of three different test methods called "Three ball-on-disc","Three pin-on-disc" and End-face in the HDM-20 friction and wear test machine,the "Three pin-on-disc" assessment method is determined finally.And the anti-scuffing performance test is executed in the condition of oil circulating and the evaluation of the anti-scuffing property with different materials is under the same test condition.The results show that the abrasion resistance of the friction material is gradually deteriorated with increase of the linear velocity at the speed of 1.0~1.4m/s.As the linear velocity increases,the corresponding scratch pressure also continue decreasing.In the velocity of 1.0~1.1m/s,the change pattern of the surface friction coefficient and friction torque of QT700-2 is W-type,and prompts would appear before the material is scratched.When the linear velocity increases,the change pattern would transform from the W-type to the U-type.However,in the linear speed of 1.0~1.4m/s,the dynamic variation of friction parameters of QAl9-4 shows a U-type trend,and no prompts appear before the abrasion of the material.Along with the vibration and noise of testing machine,the serious damage occurred directly.On the comprehensive macroscopic and microscopic analysis of the detection results of abrasion morphologyon friction material at different linear speeds for different time periods by scanning electron microscopy(SEM)and EDS microscopic,the friction coefficient of materials occurred steep before the first-level load should be selected as the scratch load point.Finally,four evaluation indexes are selected to evaluate the anti-scuffing performance of different materials under the same condition.Compared with the PV value method,the results show that the multi-index comprehensive evaluation method has better reliability.