| For a long time,there is an excellent characteristic of oil resistance in Nitrile Buladience Rubber(NBR),so NBR is used in petrochemical and automotive industry massively.However,with the properties of mechatronic equipments continuously improved,people have an increasing strict requirement on seal conditions under such conditions as high rate,high or low temperature,deep-etching and so on.NBR is noncrystalline and unbodied polymer,whose tensile-strength is very low, about only 3MPa.Thus,it must be enhanced so as to be useful.By adding the black pigment,tensile-strength of NBR could be up to 15～25MPa, with the forced coefficient 4～12.But improving the hardness of NBR was only by black pigment and other enhancer,NBR's hardness will be difficult of to improve further,as well as its elastane and extensibility of valcanisate will also not meet the needs of application.In this case, improving the wear-resistant and antifriction properties become an urgent problem.Friction and wear are prombles in the direct contact seal.Because seal components contact,fraction is produced,which cause the fever and the wear of the surface of the parts.And this is just the main reason for leaking and breakage of sealing.The oil resistance of NBR is better than common rubbers,so NBR is widely used by sealing products.However, in the process of using NBR,it also has its bad qualities,such as a big friction,easy to wear,a short product life,etc.Friction and wear of rubber productions were reduced by reducing fraction coefficient. Application of mixing modify in NBR can improve properties,such as fraction coefficient,wear-resistant,physical and mechanical and magnetic properties.And,nano-NdFeB magnetic particles and NBR was excellent magnetic composite by chemical mixing.Because magnetic rubber used in petrochemical and automotive industry is put forward,Nano-NdFeB particles are impregnated in NBR in this research so as that a litter particles can get high magnetic as the same large NBA particles.Nano- NdFeB by modified can be better combined with common back pigment and sheet rubber,magnetic NanoNdFeB NBR is made;substituting back pigment by nano-magnetic is also studied in this research.Proof sample was made up by NBR of substrate materal and magnitic NdFeB of filler.Physical and mechanical properties and tribology properties under oil lubrication were tested,the effect of magnetic particles on NBR was evaluated.Friction resistance and antic-attrition mechanism of magnetic NdFeBr modified-NBR were discussed.The purpose is to improve friction resistance and antic-attrition mechanism of material.Nature of modified-NBR was studied,in order to supply experiment data of designing and production of NBR sealing.This project analyzes the surface friction,wear and lubrication and magnetic properties of of Nano-NdFeB,by taking the way of a dry subject of magnetic NdFeB NBR composite material and testing its mechanical properties,magnetic properties as well as its friction properties in the state of oil friction.In summary,the results of this research are as follows:1)After nano- NdFeB MNBR is prepared,with the particles increasing, hardness is improved.The tensile-strength increases first,and then decreases;Then,a hump turns up;The elongation at break decreases;2)After nano- NdFeB MNBR is prepared,compared with NBR, fraction coefficient and wear rate are litter under a dry condition; When the NdFeB particles filled is 15%,fraction factor reaches the least.3)When there are better magnetic force and coercive force in MNdFeB which can compensate stress of sealing,the sealing capacity and length of life will be improved.
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