Abstract: An abrasive cutter formed of at least one diamond particle, preferably at least one mono-diamond crystal and metallic binder material distinguished by the fact that the diamond particle (D) has a size of about 50 &mgr;m to about 500 &mgr;m and each diamond particle (D) is enclosed by a coating (H) produced in a fluidized bed with the coating having a wall thickness of about 10 &mgr;m to about 200 &mgr;m. The volume of the coating (H) constitutes at least 30% of the volume of the diamond particles (D) in the fully consolidated state following individual sintering of the coated diamond particles (D, H). The abrasive cutters can be applied directly onto an abrasive tool. Further they can be processed to form composite cutters or cutting segments. In the method of forming the abrasive cutter, the diamond particle (D) is brought into a fluidized bed reactor and enclosed in a metallic coating (H).

Abstract: A composite cutting tool for use in the abrasive processing of hard substrates comprising cutting elements wherein diamond particles in a predominantly metallic binder material are agglomerated and sintered during an individual molding process of each of said cutting elements.

Abstract: A cutting member to be connected to a material removing device such as an annular bit, a drilling bit, a cutting bit, a saw and the like, consists of a binder agent, diamond grains and a small amount of hard material particles. The hard material particles reinforce the binder agent and supports the anchorage of the diamond grains.

Abstract: A hollow drilling tool is made up of an axially extending tubular carrier part, a cutting body at one end of the carrier part, and guide elements located in the axial direction of the carrier part between the cutting body and the carrier part. The radially outer surface of each guide element is in alignment in the axial direction of the carrier part with the radially outer surface of the cutting body. The guide elements guide the hollow drilling tool in a borehole formed by the cutting body.

Abstract: A hollow drill bit is formed of an axially extending tubularly-shaped support member (1) with cutter elements (2) inserted into the leading end (1a) of the support member. Each cutter member (2) has a radially outer surface (2a) and a radially inner surface (2b) with channels (2c, 2d) in each surface inclined relative to the axis of the support member (1). The channels (2c,2d) carry a flowable cooling agent to the leading end of the drill bit, and remove drillings produced by the bit from the leading end.