Super-hard CBN grinding wheel and preparation method thereof

Abstract

The invention discloses a super-hard CBN grinding wheel and a preparation method thereof, and belongs to the field of super-hard abrasives. The grinding wheel comprises a steel core and an abrasive ring. The steel core and the abrasive ring are combined by a resin binder and a resin adhesive. The abrasive ring is prepared by a CBN abrasive, a metal bond and an auxiliary binder. The metal bond contains Cu60Sn40 powder and TiH<2> powder. The abrasive ring is composed of the CBN abrasive, the metal bond and pores. The preparation method comprises the steps that (1) the CBN abrasive, the Cu60Sn40powder and the TiH<2> powder are mixed to obtain a mixture A; (2) the auxiliary binder is mixed with the mixture A to obtain a mixture B; (3) the mixture B is dried; (4) the dried mixture B is sieved;(5) the sieved mixture B is subjected to cold press forming to obtain a green body of the abrasive ring; (6) the green body of the abrasive ring is sintered in an inert atmosphere and then cooled toobtain a blank of the abrasive ring; and (7) the blank of the abrasive ring is bonded to the steel core with the resin adhesive to obtain the super-hard CBN grinding wheel.

Description

technical field [0001] The invention relates to the field of superhard abrasives, in particular to a superhard CBN grinding wheel and a preparation method thereof. Background technique [0002] With the development of modern machining in the direction of high precision, high speed, hard machining, dry machining (no coolant) and cost reduction, quite high requirements are put forward for the performance of abrasive tools. Traditional silicon carbide and corundum ordinary abrasive molds can no longer fully meet the current high-speed, high-efficiency, and high-precision grinding requirements. Therefore, it is an inevitable development to develop various superhard grinding materials with excellent wear resistance and stable processing for a long time trend. Currently commonly used superhard grinding materials include cubic boron nitride (CBN) and diamond abrasives. Although the hardness of cubic boron nitride abrasive is lower than that of diamond, it is still much higher tha...

AI Technical Summary

Problems solved by technology

Traditional superhard abrasives (grinding wheels) are mostly manufactured by resin, ceramics, metal bond sintering and electroplating. The problem is that single crystal particles are only mechanically embedded in the bond and electroplating layer, and bond and Weak force between plating layers

Specifically, although the resin bond is relatively easy to process and repair, it has poor heat resistance, low bonding strength, serious abrasive shedding, and seriously affects efficiency; the vitrified bond is relatively easy to repair and has a high service temperature, but it is brittle and impact toughness. Poor fatigue, prone to brittle cracking, difficult to use in high-speed machining

Although metal bond sintering has strong heat resistance, chemical metallurgical bonding cannot occur between the bond and the abrasive grains, so the abrasive grains are only mechanically embedded in the bond with limited holding power; abrasive grains in metal electroplating are only mechanically embedded

Therefore, it is easy to cause the overall failure of the grinding wheel due to the particle shedding of the abrasive and the peeling off of the coating in flakes. This situation is especially obvious when the more difficult-to-process materials are efficiently ground; in addition, the coating is thick, the exposure height of the abrasive is low, and the chip space is small. , it is easy to fail due to the adhesion and clogging of chips during grinding