| Fe-based sintered material has good mechanical properties,but has poor antifriction performance.Polymer material has very good tribological properties.It is easy to form transfer film between the friction surfaces in friction process.But it has poor heat resistance and abrasion resistance.Therefore,in order to improve such defect of Fe-base material and polymer material,use metal as the matrix and use polymer material as the antifriction phase to produce composite material.Matrix material is made through the method of powder metallurgy.The base powder is low alloy steel powder,and by adding Cr-Fe powder and change the sintering temperature to improve the material performance of base material.Test the density,hardness and compressive strength of matrix material,and observe the microstructure of matrix material.Then infiltrate PEEK in the matrix material.And observate infiltration results through metallographic microscope.Test the friction and wear performance of the matrix material sample and infiltrated sample with the friction and wear testing machine.Observe worn surface by scanning electron microscope(SEM)and 3D laser scanner.Then analysis chemical composition of the worn surface,discuss the the friction and wear mechanism of infiltrated PEEK material.The research results show that with the increasing of sintering temperature,the quantity and size of pore of low alloy steel is decreased obviously.Density,hardness and compressive strength rise with the temperature.With temperature rising from 1150 to 1350 ℃,density rise from 6.37 to 6.75 g/cm~3,compressive strength rise from 669 to 1191 Mpa,hardness rise from 69 to80 HRB.Under the sintering temperature of 1250 ℃,with the increasing of Cr-Fe powder content,the number of the pore is decreased,but the size of the pore is increased.Pearlite is gradually reduced,ferrite increased,and the martensite present.Hardness of material increased,density and compressive strength decreases.With Cr-Fe powder content rising from 0 to 4%,density decrease from 6.55 to 6.28 g/cm~3,compressive strength decrease from 884 to 380 Mpa,hardness increase from 72 to 93 HRB.Friction coefficient of infiltration PEEK sample is very small for a period of time,at around 0.03.After a period of time,the friction coefficient increases to 0.1.The smaller the density is,the longer running time at the friction coefficient of 0.03 is.As a whole,anti-friction effect of samples after infiltration PEEK has increased significantly.This is because PEEK swells under the high temperature.And the lubricating film is formed between the friction surfaces.But the duration and load bearing of lubrication film are not ideal.It can be seen from the wear surface morphology that wear before and after infiltrate PEEK are Adhesive peel.The depth of peeling pit is shallow.And abrasion loss is significantly reduced after infiltrate PEEK. |
