片状超细WS_2粉末的制备及其润滑性能研究

Preparation and Tribological Properties of Sheet-like Fine WS_2 Powder

当WS2粉末的基面与材料表面平行时，润滑效果最好，因此纳米片状形貌能极大地改善WS2粉末的润滑效果。为制备纳米片状WS2粉末，将分析纯WO3和S粉末在氩气保护下进行球磨，将球磨后的混合粉末在硫蒸气气氛中进行硫化得到WS2粉末。基于XRD和SEM的成分和形貌分析表明，通过球磨加硫化的方法成功制备出边缘长度在250—500nm，厚度小于100nm的片状超细WS2粉末。将片状超细WS2粉末添加到石蜡油中进行标准四球摩擦试验，结果表明：该粉末可显著提高石蜡油最大无卡咬负荷值，同时有效减小磨斑直径，其中质量分数1．3％的片状超细WS2粉末可使石蜡油的最大无卡咬负荷值增加118N，质量分数1．5％的片状超细WS2粉末可使试样的平均磨斑直径减小0．33mm。

When the base planes of WS2 particles are parallel to the surface of metal, the tribological performance will be the best. Therefore,2D sheet-like nanostructures can greatly improve its tribological properties. To obtain such mierostrue- tures, a mixture of analytically pure WO3 and S powder was energetically ball-milled in Ar atmosphere, the ball-milled mixture was sulfurized in sulfur vapor. XRD phase detection and SEM morphology observation shows that sheet-like and fine WS2 powder with edge length between 250 - 500 nm and thickness less than 100 nm is obtained through the route of ball- milling to sulfuration. The obtained product was added into liquid paraffin to investigate its tribologieal behavior using standard four-ball test method. The result shows that the powder ean inerease the maximum non-seizure load of liquid par- affin and decrease the average wear scar diameter of the below balls obviously. The maximum non-seizure load value increases 118 N when adding 1.3% WS2 powder and the average wear diameter decreases 0. 33 mm when adding 1.5% WS2 powder.