Experiments On Friction And Wear Of 45 Steel With Small Displacemen Tunder The Condition Of Magnetic Field

With the development of societyand the advancement of science and technology, especially the magnetism application technology maturing, it is increasingly common that friction pairs have to work in the magnetic environment. It is of great significance to reduce friction and wear, prolong the life of friction pair, improve friction efficiency and reliability under magnetic field.A fixture was designedtoclampthe DCcoil for excitation in the study. Thesamplesused in the experiments were designed and processed. Experimentalscheme and process was made.Experiments were tested on the HSR-2Mreciprocating friction andweartesting machine.As known to us, 45 steel is widely used in the machinery manufacturing industry. It is set to be the main studying object in this paper. At first, experiments of discs and pins made of 45 steel were carried out in the DC steady magnetic field condition. Then, experiments of GCr15 steel balls and 45 steel discs were carried out in the condition of permanent magnetic field. Effects of the load, magnetic flux density and other parameters on the friction and wear properties have been studied in both experimental conditions. While metallographical microscopeand other instruments were adoptedto test and analyze the worn surface morphology. Details are as follows:The influence of magnetic flux density on friction and wear properties of the two conditions was studied. The results showed that the magnetic field can effectively reduce the friction coefficient, lower the wear rate. Wear performance of 45 steel pin/disc friction pair and GCr15 steel ball/45 steel disc friction pair can be improved in the magnetic field.The influence of velocity on friction and wear properties of GCr15 steel ball and 45 steel disc friction pair in the permanent magnetic fieldwas studied. The results showed that, under the same load and magnetic flux density, with the sliding velocity increasing, the wear rate and the friction coefficient decreased.With the same magnetic flux density and sliding velocity, the influence of load on friction and wear properties of the two conditions was studied. The results showed that with the load increasing, the friction coefficient decreased, while the wear rate increased.In the DC steady magnetic field conditions, wear was mainly adhesive wear, spalling and slightly oxidized wear. With the load increasing, the frictional heat increased, plastic deformation of friction pair surface enhanced, and the amount of wear loss increased. At the same time, the actual contact area of the friction pair surface increased, resulting in friction coefficient reduced.Applying a magnetic field of the permanent magnetcan reduce the wear of 45 steel and GCr15 Steel. Without magnetic field, wear was a typical abrasive wear, and worn surface was obviously furrowed. The friction coefficient and wear rate was greater than that in the existing of magnet field.With a magnetic field, the wear was mainly in the form of wear adhesive.Under the conditions of the permanent magnet field, the increasing load made the wear condition worse. With the increasing of load, the adhesion wearbecame worse. While shedding phenomenon enhanced.Under the conditions of the permanent magnet field, the increasing of velocity wasconducive to the reduction of friction and wear. It made the wear transformedfrom more severe form of adhesive wear into a mild adhesive wear.