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Transitional metal selenide MSe2（M=W,Mo,Nb） have lamellar close-packed hexagonal structures,was used as solid lubricants extensively.The dangling bonds on the edge of crystal have chemical activity,and to be oxidized easily in ambition,especially in humanity conditions,the friction properties of lubricants decrease.The unique closed one dimensional nanostructure（nanotubes,nanowires,nanobundles） formed with rolled up MSe2（M= Mo,W,Nb） materials have eliminated the fringe dangling bonds,thereafter they improves the chemical stability and have very expansive application prospects on tribology.In this article,experimental investigation and theoretical analysis were carried out on the preparation process and tribology properties of transitional metal selenide MSe2（M=W, Mo,Nb） nanostructures.Firstly,MoSe2、WSe2and NbSe2 nanoflake were obtained by heating sealed quartz ampoules by mixed Se and Mo,W and Nb in high temperature boxed furnace.And the products’ component and microstructure of MSe2 nanostructue were investigated by means of X-ray diffraction（XRD）,scanning electronic microscope（SEM） and transmission electronic microscope（TEM）.Secondly,take example for WSe2,the growth and conditions of nanowires and nanoparticles were discussed including reaction temperature,keep temperature time,reducing temperature velocity,flux of gas,coefficient of exceeding Se and so on.The growth mechanism of MSe2 nanostructures were discussed rational.Thirdly,MoSe2、WSe2 and NbSe2 were added in different base oil as additives,the tribological properties of MoSe2、NbSe2 and WSe2 were tested by CETR UMT-2 Tester in different conditions and different locomotion form and discussed the tdbology properties in simple.Fourthly,the friction mechanism of lubrication including MSe2 as additives was discussed preliminary by means of the tribology properties test of the oil.The lubrication has excellent tribology properties may be due to the following factors:one dimensional nanomaterials have unique structures,lubrication films and fill up -repair mechanism.At last,to analyse the properties of antifi-iction and antiwear of Mse2 when it is used as additives by the test of Electrical Contact Resistance.At the meantime,because of the change of normal coordinates Zc,it will lead the coefficient changed slightly,so we can analyse the role of the nanomaterials when it is used as additives.
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