techniques that would be complementary to such models. This paper describes one step in a sequence of research efforts that is intended to lead to the adaptive control of unattended machine tools. Numerical parameters are used to evaluate coefficients of a previously developed state space model of semi-orthogonal metal cutting on a lathe. An advanced continuous simulation language (ACSL) program is presented. 19 Refs.

8, T. Waida, H. Noguchi, M. Rezaei, T. Suto, "Creep feed grinding of ceramics and ceramic-matrix composites with slotted & perforated wheels," Journal of the Japan Society of Precision Engineering, 57(2), pp. 324-329. (Feb 1991). Electroplated and vitrified bonded diamond grinding wheels with unique structure were newly developed which have slots/segments and cooling holes in the wheel working surface for creep feed grinding of ceramic materials. Silicon nitride was ground with 64% of the grinding power required with a conventional wheel. Wear flats of diamond grits on the leading edge and trailing edge of the cutting segments were observed. Residual stresses of the ground surface of ceramics were measured by the X-ray diffraction method. Aluminum reinforced alumina was slightly easier to grind than alumina, but its surface finish was 150% as rough as that of alumina. Carbon fiber reinforced silicon nitride was ground with 44% of the grinding power required for silicon nitride, in the case when the grinding direction was normal to the fibers, but its surface roughness increased by 130% compared with that for silicon nitride. When the grinding direction was longitudinal, the grinding power was 10%, but the surface roughness increased by a factor of four. Specific energy for grinding ceramic composites with the newly developed wheel does not increase with increasing wheel depth of cut up to 8 mm. 8 Refs.

9, C. Evans, "Cryogenic diamond turning of stainless steel," 41st General Assembly of CIRP, Manufacturing Technology, Vol 40 n 1, Aug 18-24, 1991. pp. 571-575. Int Inst for Production Engineering Research. Berne, Switz. Tool wear is extremely rapid when ferrous materials are single point diamond turned. This paper reviews diamond tool wear mechanisms, showing that both fracture and chemical mechanisms may be important. The rate of all chemical reactions increases exponentially with temperature. Hence tool wear may be reduced significantly by machining at cryogenic temperatures. A cryogenic machining system comprising tool post and chuck with constrained liquid nitrogen flows has been built. Using this system a number of 35 mm diameter, 400 series stainless steel flats have been diamond turned. Surface finish is better than 25 nm R a. 42 Refs.

10, K. Suzuki, T. Uematsu, T. Yanase, M. Honma, S. Asano, "Development of a simplified electrochemical dressing method with twin electrodes," 41st Genera/Assembly of CIRP, Manufacturing Technology, Vol 40 n 1, Aug 18-24, 1991. pp. 363-366. Int Inst for Production Engineering Research. Berne, Switz. The paper deals with a newly developed method for electrochemical dressing of metal bonded superabrasive wheels. In this method, alternating current derived from a wall outlet via an inexpensive transformer is supplied to a wheel through twin electrodes, hence a troublesome brush and an expensive DC power source are unnecessary. The preprocess dressing of a wheel (ds equals 200 ram) was accomplished within a few minutes. Inprocess dressing of a wheel resulted in lower grinding force, longer wheel life and higher grinding efficiency in grinding of ceramic materials and hard metals. 6 Refs.

11, J. Ikeno, Y. Tani, A. Fukutani, "Development of chipping-free dicing technology applying electrophoretic deposition of ultrafine abrasives," 41st Genera/Assembly of C/RP, Manufacturing Technology, Vol 40 n 1, Aug 18-24, 1991. pp. 351-354. Int Inst for Production Engineering Research. Berne, Switz. It is very important to decrease the amount of chipping in the dicing process of brittle materials for the reduction of material loss and the improvement of surface integrity in the production of optical and electrical components. The use of ultrafine abrasives reduces the grain depth of cut which results in the minimization of subsurface damage. Thus, a new dicing technology has been developed by applying electrophoretic deposition of ultrafine abrasives. During the process, the abrasives cohered around a conductive thin blade used as the anode in an electric field and polished the side surfaces of grooves. Consequently, chipping-free dicing was accomplished and an optically smooth surface was obtained on the side surfaces of the groove. 8 Refs.

12, T. Horiuchi, S. Matsui, "Development of optically controlled automatic balancer for grinding wheel , " Journal of the Japan Society of Precision Engineering, 57(2), pp. 245-249. (Feb 1991). This paper describes a non-contact type automatic wheel balancer which is operated by photo signals. It consists of driving mechanisms for balancing weights, actuators, power sources, control circuits and photo transistors. The photo transistors receive signals from the photo diodes which are set on a wheel cover. Thus, the rotating balancer can be operated under non-contact condition. Using this balancer, vibration amplitude on a wheel head of a surface grinder can be reduced to less than 0.05 ~m in any cases. 5 Refs.

13, F. Tagliabue, "Diamond grinding of cermets," Materials & Design, 12(4), pp. 209-212. (Aug 1991). The paper describes some test results obtained in the diamond grinding of modern cermet tool materials, which are becoming more widely used in the metalworking industry. In general, a relatively low G-ratio, low material removal rate and high power consumption will be observed. A rigid grinding machine is needed, with no vibrations and adequate spindle motor power. 7 Refs.

14, K. Takeuchi, T. Sugano, Y. Yoshida, "Diamond turning of oxygen free copper for metal mirrors. 2nd Report. Selection of raw materials for mirrors and machining test over long cutting distances," Journal of Mechanical Engineering Laboratory, 45(4), pp. 169-177. (Jul 1991). The fundamental data of ultra precision turning of the oxygen free copper (OFC) for mirrors were reported in the previous paper. This paper deals especially with the diamond turning of high purity OFC (class 1). The machining test were carried out about (1) the selection of suitable material for diamond turning from four kinds of raw materials, and (2) the mirror finishing properties of the raw material selected in (1) over long cutting distances. The test results may be summarized as follows: (1) The raw material produced by the processes of hot roll, cold roll and heat treatment (annealing) is most suitable in aspect of surface integrity. (2) The surface roughness and the cutting forces are stable in the range up to 500 km of cutting distance. The compressive residual stresses of surface increase gradually from 20 MPa at initial cutting to 50 MPa at the cutting distance of 300 km, and after that become stable. As for the

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tool wear, the crater wear is especially remarkable, but on the other hand, flank wear is negligible small. These phenomena are different from those of diamond turning of AI alloy. 5 Refs. In Japanese.

15, W. S. Blackley, R. O. Scattergood, "Ductile-regime machining model for diamond turning of brittle materials," Precision Engineering, 13(2), pp. 95-103. (Apr 1991). A new machining model has been developed for single point diamond turning of brittle materials. Experiments using the interrupted cutting method allow model parameters to be determined that provide a quantitative method for determining the machinability of a material with respect to the rake angle, tool nose radius and machining environment. The model uses two parameters, the critical depth of cut and the subsurface damage depth, to characterize the ductile-regime material removal process. Also included in the model is a parameter used to set a process limit defined as the maximum feed rate. Machining experiments have verified the model, and allow for determination of optimum machining conditions. 9 Refs.

16, F. S. Entelis, V. N. Nazarova, G. A. Bogdanova, "Effect of abrasive grain size on glass surface texture," Steklo i Keramika v 9 n 2 Feb 1991 p 27, (1991). The possibility to obtain tarnished surfaces of various roughness by glass treatment with abrasives of different granulometric composition has been investigated. Sand blasting of BF-105 flint glass and LK-106 crown glass is performed using ejector with spray length of 100 mm, air pressure 3.5 MPa during 10 s. The tests show that application of abrasive powders with particle size 15, 35, 65, 100 and 500 I~m allows one to finish glass surfaces and obtain wide range of textures. In Russian.

17, A. E. Bayoumi, Q. Xie, M. N. Hamdan, "Effect of cutting conditions on dynamic properties and surface integrity of work material," Wear, 146(2), pp. 301-312. (Jun 28, 1991). An investigation of orthogonal metal machining was carried out to characterize workpiece materials and to correlate the findings of shear stress, shear strain and strain rate under a wide range of cutting conditions to the induced surface integrity of the machined surface. Standard materials testing techniques are widely known and applied in the dynamic range of deformation, but results of such methods cannot be generalized to reflect the condition of a workpiece being machined. This work involves the study of the machined surface integrity in the form of residual stress, strain and subsurface energy for a wide range of conditions. An attempt was made to relate the surface integrity to the dynamic characterization of the workpiece materials. It was found that an increase in cutting speed or feed rate led to a decrease in the average shear strain. It was also found that the average shear stress was constant for different cutting conditions. It was concluded from this research that an increase in cutting speed or a decrease in feed rate will lead to improvements in the machined surface integrity and reduction in the machining energy consumption. 17 Refs.

18, M. Mochida, H. Suzuki, T. Shimamune, "Effects of grinding conditions on the ground surface aspects of fine ceramics (1st report). Forming mechanism of ground surface in case of SiC, Si3N 4 and AI203, " Journal of the Japan Society of Precision Engineering, 57(2), pp. 304-309. (Feb 1991 ). In precision grinding of normal sintered fine ceramics of silicon carbide, silicon nitride and alumina, the effects of grinding conditions on the ground surface aspects and the removal mechanism of these materials are investigated experimentally. As the results, the following facts are clarified. (1) When the cutting area of an abrasive grain or wheel speed is reduced, the proportion of brittle fracture area on the ground surface decreases and so surface roughness becomes small. (2) The surface roughness depends strongly on the trace of brittle fracture. (3) As the cutting area of an abrasive grain becomes small, the removal mechanism of materials changes to plastic deformation type from brittle fracture type. (4) The lower wheel speed is, the larger the critical cutting area which material removal of an abrasive grain is caused by plastic deformation becomes. The value of silicon carbide is larger than the value of silicon nitride, 2 Refs.

19, R. Crase, "Effects of polishing materials on the laser damage threshold of optical coatings," 22nd Annual Boulder Damage Symposium on Laser-Induced Damage in Optical Materials, Vol 1441, pp. 381-389, Oct 24-26, 1990. Int Soc for Optical Engineering. Bellingham, WA. This paper reports the effects of polishing material on the laser damage threshold of optical coatings. Two identical sets of BK-7 glass windows were polished to a laser quality surface finish. One set was polished with cerium dioxide (CeO2) and the second set was polished with a soft zirconia (ZrO2). Samples of each type were coated with electron beam evaporated dielectric coatings. After coating, the samples were then tested to determine their relative damage threshold. The results for each polish type were then compared. Implications for the use of zirconia as an alternative polishing material for high power laser optics is presented. 1 Ref.

20, T. Masuzawa, M. Kimura, "Electrochemical surface finishing of tungsten carbide al loy," 41st Genera/ Assembly of CIRP, Manufacturing Technology, Vol 40 n 1, Aug 18-24, 1991. pp. 199-202. Int Inst for Production Engineering Research. Berne, Switz. This paper deals with an experimental study on finishing the surface of tungsten carbide alloy. A special design of the pulse train for alternate polarity ECM is proposed for realizing a uniform dissolution of tungsten carbide and for suppressing the dissolution of the tool electrode. The effectiveness was confirmed by applying the pulse on an EDMed surface. A smooth surface without heat-affected layer or cracks was obtained. The experiments also led to hints for selecting the electrode material. 3 Refs.

21, J. W. Dini, "Electroless vs electrodeposited Ni-P alloys for diamond turning applications," Electroless Nickel 91, (Jul 1991). 20 pages. (UCRL-JC-107839). Electrolytes nickel deposits with greater than 10% phosphorous have been widely used for diamond turning applications such as fabrications of large optics and other high precision parts. Although the coatings have worked well, they are not without their drawbacks. Porosity and nodule formation have been problems as well as the difficulty of obtaining deposits greater than about 75 I~m. In recent years much effort has been directed at the investigating electrodeposition of Ni-P alloys in an attempt to avoid these problems. The purpose of this paper is to compare diamond turning results for both electroless and electrodeposited alloys and speculate about the future uses of electrodeposited Ni-P for precision finishing applications. 16 refs., 7 figs.

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