【正文】 s not normally acpanied by a proportional reduction in the tangential grinding force, and thus results in an increase in process power. Reducing the length of time the abrasive grain is in contact with the work piece can reduce the quantity of heat into the work piece. An increase in the machining rate of the process is necessary for this to happen, where the chip thickness is increased to the level that applies to lower cutting speeds without overloading the grinding wheel. Experimental results [3] illustrate that increasing the cutting speed by a factor of two while maintaining the same metal removal rate leads to a reduction in the tangential force but, unfortunately, leads to an increase in the amount of work done. Owing to constant grinding time, there is an increase in the process energy per work piece and, subsequently, in the total thermal energy generated. When the material removal rate is also increased the rising tangential force results in a further increase in grinding power. The quantity of thermal energy introduced into the work piece is lower than the initial situation when the samemachined work piece volume applies despite the higher cutting speed and increased metal removal rate. These considerations show that machining productivity can be increased using highspeed grinding without having to accept undesirable thermal effects on ground ponents. There are three fields of technology that have bee established for highspeed grinding. These are 1. Highspeed grinding with CBN grinding wheels. 2. Highspeed grinding with aluminum oxide grinding wheels. 3. Grinding with aluminum oxide grinding wheels in conjunction with continuous dressing techniques (CD grinding). Material removal rates resulting in a super proportional increase in productivity for ponent machining have been achieved for each of these fields of technology in industrial applications [4,5] (Fig. 1). High equivalent chip thickness of between and 10 mm are a characteristic feature of highspeed grinding. CBN highspeed grinding is employed for a large proportion of these applications. An essential characteristic of this technology is that the performance of CBN is utilized when high cutting speeds are employed. 3. Grinding tools for highspeed grinding CBN grinding tools for highspeed machining are subject to special requirements regarding resistance to fracture and wear. Good damping characteristics, high rigidity, and good thermal conductivity are also desirable. Such tools normally consist of a body of high mechanical strength and a parably thin coating of abrasive attached to the body using a highstrength adhesive. The suitability of cubic boron nitride as an abrasive material for highspeed machining of ferrous materials is attributed to its extreme hardness and its thermal and chemical durability. High cutting speeds are attainable above all with metal bonding systems (Fig. 2). One method that uses such bonding systems is electroplating, where grinding wheels are produced with a singlelayer coating of abrasive CBN grain material. The electrodeposited nickel bond displays outstanding grain retention properties. This provides a highlevel grain projection and large chip spaces. Cutting speeds of 280 m s1 are possible [6]. The service life ends when the abrasive layer wears out. The high roughness of the cutting surfaces of electroplated CBN grinding wheels has disadvantageous effects. The high roughness is accountable to exposed grain tips that result from different grain shapes and grain diameters. Although electroplated CBN grinding wheels are not considered to be dressable in the conventional sense, the resultant workpiece surface roughness can nevertheless be influenced within narrow limits by means of a socalled touchdressing process. This involves removing the peripheral grain tips from the abrasive coating by means of very small dressing infeed steps in the range of dressing depths of cut between 2 and 4 mm, thereby reducing the effective roughness of the grinding wheel [7]. Multilayer bonding systems for CBN grinding wheels include sintered metal bonds, resin bonds, and vitrified bonds. Multilayer metal bonds possess high bond hardness and wear resistance. Profiling and sharpening these tools is a plex process, however, on account o