Grinding Characteristics of MoS2-Coated Brazed CBN Grinding Wheels in Dry Grinding of Titanium Alloy

Abstract

As an important green manufacturing process, dry grinding has problems such as high grinding temperature and insufficient cooling capacity. Aiming at the problems of sticking and burns in dry grinding of titanium alloys, grinding performance evaluation of molybdenum disulfide (MoS2) solid lubricant coated brazed cubic boron carbide (CBN) grinding wheel (MoS2-coated CBN wheel) in dry grinding titanium alloys was carried out. The lubrication mechanism of MoS2 in the grinding process is analyzed, and the MoS2-coated CBN wheel is prepared. The results show that the MoS2 solid lubricant can form a lubricating film on the ground surface and reduce the friction coefficient and grinding force. Within the experimental parameters, normal grinding force decreased by 42.5%, and tangential grinding force decreased by 28.1%. MoS2 lubricant can effectively improve the heat dissipation effect of titanium alloy grinding arc area. Compared with common CBN grinding wheel, MoS2-coated CBN wheel has lower grinding temperature. When the grinding depth reaches 20 μm, the grinding temperature decreased by 30.5%. The wear of CBN grains of grinding wheel were analyzed by mathematical statistical method. MoS2 lubricating coating can essentially decrease the wear of grains, reduce the adhesion of titanium alloy chip, prolong the service life of grinding wheel, and help to enhance the surface quality of workpiece. This research provides high-quality and efficient technical support for titanium alloy grinding.