Research On The Friction And Wear Properties Of Different Magnetic Materials Under The Condition Of Magnetic Field

In this paper, ferro magnetic material(45steel)and nonferromugnetic material2A12-T4aluminum alloy are the main object of study by friction pair45steel/45steel,2A12-T4aluminum alloy pin/2A12-T4aluminum alloy ring and2A12-T4aluminum alloy pin/45steel ring, using modified post-MPV-1500friction and weartesting machine model to study the influence of different condition includingmagnetic field,load and velocity on ferro magnetic material (45steel) andnonferromugnetic material2A12-T4aluminum alloy about materials friction andwear properties. At the same time,the wear surface of the different material pinsspecimen were carried on the microscopic analysis by3d profilometer,scanningelectron microscope with energy spectrum instrument and so on. Specific content asfollows:The influence of magnetic field on friction and wear properties of differentmaterials was studied, the results show that: for ferromagnetic material, comparedwith no magnetic field, magnetic field can reduce the wear rate and the frictioncoefficient of pin of45steel, which shows that magnetic field can improve theferromagnetic material friction performance. For nonferromugnetic material,compared with no magnetic field, magnetic field make the wear rate and frictioncoefficient of2A12T4aluminum alloy pin increase,so that friction and wearperformance was deteriorated,which Shows that magnetic field applied againstnonferromugnetic material2A12-T4aluminum alloy abrasion resistance increased.The influence of load on friction and wear properties of different materials wasstudied, results show that under the condition of the same speed and magnetic fieldintensity, load applied can make the friction coefficient and wear rate of friction pairincrease. For friction pair containing magnetic material (45steel since the pair of45steel and aluminum alloy with pair), the presence of a magnetic field has better friction performance; For friction pair containing no magnetic material(2A12-T4aluminum alloy pin/2A12-T4aluminum alloy ring),the result is opposite.The influence of velocity on friction and wear properties of different materialswas studied, results show that under the condition of the same load and magneticfield intensity, the wear rate of friction pair increases and the friction coefficientreduces with the increase of velocity. For friction pair containing magnetic material(45steel since the pair of45steel and aluminum alloy with pair), the presence of amagnetic field has better friction performance; For friction pair containing nomagnetic material(2A12-T4aluminum alloy pin/2A12-T4aluminum alloy ring),theresult is opposite.Under the same conditions, the influence of constant magnetic field ontribological behaviour of quenching and annealing45steel pin against45steel discwas investigated.The results indicated that constant magnetic field can make thesurface roughness reduced, as a result, the friction coefficient and wear loss wasreduced. within the scope of the magnetic field, quenching45steel has less effect bymagnetic field,however, annealing45steel is contrary to that.Both of them about themechanism of wear was similar. the mechanism ia abrasive wear attrition without amagnetic field and adhesion wear in the field.With the instrument of electron microscopy (SEM) and spectrometer(EDS),microscopic analysis and component analysis on the worn surface of differentmaterials were carried on. Results show that the magnetic field of the surface offerromagnetic materials have more abrasive dust,worn surface is notclean;however,the wear surface of nonferromugnetic material2A12-T4aluminumalloy has less abrasive dust, the surface is cleaner. Applying direct magnetic field canmake the oxygen content of the wear surface of ferromagnetic material increasedobviously, make the proportion of abrasive wear smaller, At the same time, moreabrasive dust absorbed isolated and lubricated the friction pair surface, improved thefriction and wear properties of ferromagnetic materials.However,the friction andwear performance of non ferromagnetic material2A12-T4aluminum alloy wasdeteriorated under the condition of direct magnetic field,the oxygen levels of wearsurface did not change obviously.