@article{guduru_darling_scattergood_koch_murty_bakkal_shih_2006, title={Shear punch tests for a bulk metallic glass}, volume={14}, ISSN={["1879-0216"]}, DOI={10.1016/j.intermet.2006.01.052}, abstractNote={A shear punch test technique was used for characterization of the mechanical properties of Zr–5Ti–17.9Cu–14.6Ni–10Al bulk metallic glass. The ultimate shear stress values matched very closely with values derived from uniaxial compression tests reported in the literature. This is consistent with a lack of pressure sensitivity in compression reported for this particular metallic glass. Deformation response was strain rate insensitive up to a critical rate, beyond which softening occurred. The latter was attributed to thermal heating effects.}, number={12}, journal={INTERMETALLICS}, author={Guduru, R. K. and Darling, K. A. and Scattergood, R. O. and Koch, C. C. and Murty, K. L. and Bakkal, M. and Shih, A. J.}, year={2006}, month={Dec}, pages={1411–1416} } @article{lemaster_shih_yu_2005, title={Blasting and erosion wear of wood using sodium bicarbonate and plastic media}, volume={55}, number={5}, journal={Forest Products Journal}, author={Lemaster, R. L. and Shih, A. J. and Yu, Z.}, year={2005}, pages={59–64} } @article{bakkal_shih_scattergood_2004, title={Chip formation, cutting forces, and tool wear in turning of Zr-based bulk metallic glass}, volume={44}, ISSN={["1879-2170"]}, DOI={10.1016/j.ijmachtools.2004.02.002}, abstractNote={The chip light emission and morphology, cutting forces, surface roughness, and tool wear in turning of Zr-based bulk metallic glass (BMG) material are investigated. Machining results are compared with those of aluminum 6061-T6 and AISI 304 stainless steel under the same cutting conditions. This study demonstrates that the high cutting speeds and tools with low thermal conductivity and rake angle activate the light emission and chip oxidation in BMG machining. For the BMG chip without light emission, serrated chip formation with adiabatic shear band and void formation is observed. The cutting force analysis further correlates the chip oxidation and specific cutting energy and shows the significant reduction of cutting forces for machining BMG at high cutting speeds. The machined surface of BMG has better surface roughness than that of the other two work materials. Some tool wear features, including the welding of chip to the tool tip and chipping of the polycrystalline cubic boron nitride (PCBN) tool edge, are reported for turning of BMG. This study concludes that BMG can be machined with good surface roughness using conventional cutting tools.}, number={9}, journal={INTERNATIONAL JOURNAL OF MACHINE TOOLS & MANUFACTURE}, author={Bakkal, M and Shih, AJ and Scattergood, RO}, year={2004}, month={Jul}, pages={915–925} } @article{hardin_shih_lemaster_2004, title={Diamond wire machining of wood}, volume={54}, number={11}, journal={Forest Products Journal}, author={Hardin, C. W. and Shih, A. J. and Lemaster, R. L.}, year={2004}, pages={50–55} } @article{bakkal_shih_scattergood_liu_2004, title={Machining of a Zr-Ti-Al-Cu-Ni metallic glass}, volume={50}, ISSN={["1359-6462"]}, DOI={10.1016/j.scriptamat.2003.11.052}, abstractNote={Zr52.5Ti5Cu17.9Ni14.6Al10 metallic glass machining chips were characterized using SEM, X-ray diffraction and nano-indentation. Above a threshold cutting speed, oxidation of the Zr produces high flash temperatures and causes crystallization. The chip morphology was unique and showed the presence of shear bands, void formation and viscous flow.}, number={5}, journal={SCRIPTA MATERIALIA}, author={Bakkal, M and Shih, AJ and Scattergood, RO and Liu, CT}, year={2004}, month={Mar}, pages={583–588} } @article{shih_scattergood_curry_yonushonis_gust_grant_mcspadden_watkins_2003, title={Cost-effective grinding of zirconia using the dense vitreous bond silicon carbide wheel}, volume={125}, ISSN={["1087-1357"]}, DOI={10.1115/1.1559167}, abstractNote={Results of grinding zirconia using wheels with fine grain size SiC and dense vitreous bond are presented. Wheel wear results demonstrated that this type of SiC wheel could grind fully and partially stabilized zirconia (PSZ) very effectively. X-ray diffraction was used to analyze the percentage of monoclinic phase in the PSZ base material, ground surface, and debris. As expected, due to the stress- and temperature-induced phase transformation during grinding, the percentage of monoclinic phase on the ground surface was increased relative to the base material. However, X-ray diffraction showed no monoclinic phase in the PSZ debris. This suggests that, during grinding, the low thermal conductivity of zirconia and SiC, compared to that of diamond, facilitates heat retention in the chip and softens the work-material. This makes the efficient grinding of PSZ possible. Grinding temperature measurement results supported this hypothesis.}, number={2}, journal={JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME}, author={Shih, AJ and Scattergood, RO and Curry, AC and Yonushonis, TM and Gust, DJ and Grant, MB and McSpadden, SB and Watkins, TR}, year={2003}, month={May}, pages={297–303} } @article{garrell_shih_lara-curzio_scattergood_2003, title={Finite-element analysis of stress concentration in ASTM D 638 tension specimens}, volume={31}, number={1}, journal={Journal of Testing and Evaluation}, author={Garrell, M. G. and Shih, A. J. and Lara-Curzio, E. and Scattergood, R. O.}, year={2003}, month={Jan}, pages={52–57} } @article{boothe_shih_kong_roberts_2003, title={Goniometric characteristics of optical fibres for temperature measurement in diesel engine exhaust filters}, volume={14}, ISSN={["1361-6501"]}, DOI={10.1088/0957-0233/14/5/305}, abstractNote={The accurate in situ, non-contact measurement of the temperature distribution within diesel after-treatment filters requires the employment of optical fibres with special tip geometry. The goniometric characteristics of optical fibres with flat, 45° angled and bent and polished tips are studied such that the specific radiation acceptance region can be determined. One 2 mm diameter fused silica and two 0.425 mm diameter sapphire optical fibres are examined. Detailed discussion of the relative intensity profiles observed for these fibres is presented. Of the three fibres evaluated, the 45° angled tip geometry provides the most precise response for measuring radiation emitted from the internal filter walls. Exploiting the characteristics of total internal reflection, the 45° angled tip fibre accepts the maximum quantity of incident radiation at an angle perpendicular to the optical axis.}, number={5}, journal={MEASUREMENT SCIENCE AND TECHNOLOGY}, author={Boothe, BJ and Shih, AJ and Kong, N and Roberts, WL}, year={2003}, month={May}, pages={563–572} } @article{curry_shih_kong_scattergood_mcspadden_2003, title={Grinding temperature measurements in magnesia-partially-stabilized zirconia using infrared spectrometry}, volume={86}, ISSN={["1551-2916"]}, DOI={10.1111/j.1151-2916.2003.tb00019.x}, abstractNote={Results of temperature measurements by analysis of the thermal emission spectra generated during grinding and subsequently transmitted through partially stabilized zirconia workpieces are presented. Portions of emitted visible and near‐infrared spectra were collected with spectrometers. Source temperatures were determined by fitting the scaled spectrometer output spectra to blackbody curves. Simulations showed that the effective temperatures determined by this method will be strongly biased toward hot‐spot (flash) temperatures, which are expected to occur at the grinding grit–workpiece interface. Hot‐spot temperatures on the order of 3000 K were obtained for grinding with both SiC and diamond wheels. These high temperatures modify the grinding process and the phase content of grinding chips.}, number={2}, journal={JOURNAL OF THE AMERICAN CERAMIC SOCIETY}, author={Curry, AC and Shih, AJ and Kong, J and Scattergood, RO and McSpadden, SB}, year={2003}, month={Feb}, pages={333–341} } @article{garrell_shih_ma_lara-curzio_scattergood_2003, title={Mechanical properties of Nylon bonded Nd-Fe-B permanent magnets}, volume={257}, ISSN={["0304-8853"]}, DOI={10.1016/S0304-8853(02)00983-6}, abstractNote={Tensile and flexural strengths as well as Young's modulus of Polyamide-11 (Nylon-11) based injection molded Nd–Fe–B magnets have been determined from −40°C to 100°C. Two types of Nd–Fe–B powders were included in this study. One is the conventional melt spun powder of irregular shape, the other is the atomized powder of spherical morphology. It was found that the tensile strength varies significantly with both test temperature and morphology of Nd–Fe–B powder. For a fixed volume fraction of magnet powder, the tensile strength decreases with increasing temperature. For bonded magnets made of melt spun powder, the tensile strength increases with increasing volume fraction of magnet powder. Specimens made of spherical atomized powders exhibit much lower tensile strength and better flexibility when compared to those made of melt spun powder. Scanning electron microscopy (SEM) analysis indicated that the debonding at the Nd–Fe–B powder and Nylon interface is the main cause of failure at 23°C and 100°C. At −40°C, a different failure mechanism with the fracture of Nd–Fe–B particle was observed on magnets prepared from melt spun powders. For the specimen containing 59.7 vol% of melt spun powder, a bending strength of 41 MPa and dynamic Young's modulus of 12.7 GPa were obtained.}, number={1}, journal={JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS}, author={Garrell, MG and Shih, AJ and Ma, BM and Lara-Curzio, E and Scattergood, RO}, year={2003}, month={Feb}, pages={32–43} } @article{garrell_ma_shih_lara-curzio_scattergood_2003, title={Mechanical properties of polyphenylene-sulfide (PPS) bonded NdFe-B permanent magnets}, volume={359}, ISSN={["0921-5093"]}, DOI={10.1016/s0921-5093(03)00400-3}, abstractNote={Mechanical properties, namely tensile and flexural strengths and elastic modulus, of polyphenylene-sulfide (PPS) bonded Nd–Fe–B magnets have been studied from −40 to 180 °C. The ultimate tensile strength (Sut) of PPS bonded magnets decreases with increasing temperature. The tensile strength of PPS bonded Nd–Fe–B magnets was reduced significantly above 100 °C. At 180 °C, the PPS bonded magnets still exhibit a Sut of 16–18 MPa. For bonded magnets with about 60% volume fraction of Nd–Fe–B powder, the PPS bonded magnet shows about twice the tensile strength and half the ultimate strain compared to that of Nylon bonded magnet. At room temperature, the flexural strength is, in general, comparable to the tensile strength. Dynamic elastic modulus measured using the impact resonance method was in good agreement with the elastic modulus obtained from tensile tests. Scanning Electron Microscopy analyses of the fractured surfaces revealed two distinct failure mechanisms. Debonding along the Nd–Fe–B particle and PPS interface is the main cause for failures at 100 and 180 °C. The fracture of Nd–Fe–B particle was observed on the fracture surface of specimens tested at −40 and 23 °C.}, number={1-2}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Garrell, MG and Ma, BM and Shih, AJ and Lara-Curzio, E and Scattergood, RO}, year={2003}, month={Oct}, pages={375–383} } @article{qu_riester_shih_scattergood_lara-curzio_watkins_2003, title={Nanoindentation characterization of surface layers of electrical discharge machined WC-Co}, volume={344}, ISSN={["0921-5093"]}, DOI={10.1016/s0921-5093(02)00395-7}, abstractNote={This study applies nanoindentation and other analysis techniques to investigate the influence of wire electrical discharge machining (EDM) process on the structure and properties of machined surface layers of WC–Co composites. Multiple indents were conducted on the cross-section of the surface recast layer, sub-surface heat-affected zone, and bulk material. The energy disperse X-ray spectrometry and X-ray diffraction were used to analyze the material compositions in the heat-affected zone and recast layer and to study the electrical spark eroded surface. The indents were inspected by scanning electron microscopy to distinguish between regular and irregular indents in these three regions. Irregular indents were caused by the porosity, soft matrix material, separation of grain boundaries, and thermal cracks caused by EDM process. The hardness and modulus of elasticity obtained from regular indents in bulk material and heat-affected zone were comparable to those of WC. It was found that the recast layer had lower hardness and modulus of elasticity than the bulk material and heat-affected zone.}, number={1-2}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Qu, J and Riester, L and Shih, AJ and Scattergood, RO and Lara-Curzio, E and Watkins, TR}, year={2003}, month={Mar}, pages={125–131} } @article{strenkowski_shih_lin_2002, title={An analytical finite element model for predicting three-dimensional tool forces and chip flow}, volume={42}, ISSN={["1879-2170"]}, DOI={10.1016/S0890-6955(01)00162-6}, abstractNote={A model of three-dimensional cutting is developed for predicting tool forces and the chip flow angle. The approach consists of coupling an orthogonal finite element cutting model with an analytical model of three-dimensional cutting. The finite element model is based on an Eulerian approach, which gives excellent agreement with measured tool forces and chip geometries. The analytical model was developed by Usui et al. [ASME J. Engng Indust. 100(1978) 222; 229], in which a minimum energy approach was used to determine the chip flow direction. The model developed by Usui required orthogonal cutting test data to determine the tool forces and chip flow angle. In this paper, a finite element model is used to supply the orthogonal cutting data for Usui's model. With this approach, a predictive model of three-dimensional cutting can be developed that does not require measured data as input. Cutting experiments are described in which good agreement was found between measured and predicted tool forces and chip flow angles for machining of AISI 1020 steel.}, number={6}, journal={INTERNATIONAL JOURNAL OF MACHINE TOOLS & MANUFACTURE}, author={Strenkowski, JS and Shih, AJ and Lin, JC}, year={2002}, month={May}, pages={723–731} } @article{qu_shih_scattergood_2002, title={Development of the cylindrical wire electrical discharge machining process, part 1: Concept, design, and material removal rate}, volume={124}, ISSN={["1528-8935"]}, DOI={10.1115/1.1475321}, abstractNote={Results of applying the wire Electrical Discharge Machining (EDM) process to generate precise cylindrical forms on hard, difficult-to-machine materials are presented. The design of a precise, flexible, and corrosion-resistant underwater rotary spindle is first introduced. A detailed spindle error analysis identifies the major sources of error at different frequency spectrum. The spindle has been added to a conventional two-axis wire EDM machine to enable the generation of free-form cylindrical geometries. The mathematical model for material removal rate of the free-form cylindrical wire EDM process is derived. Experiments were conducted to explore the maximum material removal rate for cylindrical and 2D wire EDM of carbide and brass work-materials. Compared to the conventional 2D wire EDM of the same work-material, higher maximum material removal rates may be achieved in the cylindrical wire EDM, possibly due to better debris flushing condition.}, number={3}, journal={JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME}, author={Qu, J and Shih, AJ and Scattergood, RO}, year={2002}, month={Aug}, pages={702–707} } @article{qu_shih_scattergood_2002, title={Development of the cylindrical wire electrical discharge machining process, part 2: Surface integrity and roundness}, volume={124}, ISSN={["1087-1357"]}, DOI={10.1115/1.1475989}, abstractNote={This study investigates the surface integrity and roundness of parts created by the cylindrical wire EDM process. A mathematical model for the arithmetic average surface roughness on the ideal surface of a cylindrical wire EDM workpiece is first derived. Effects of wire feed rate and part rotational speed on the surface finish and roundness for brass and carbide work-materials at high material removal rates are investigated. The pulse on-time and wire feed rate are varied to explore the best possible surface finish and roundness achievable by the cylindrical wire EDM process. This study has demonstrated that, for carbide parts, an arithmetic average surface roughness and roundness as low as 0.68 and 1.7 μm, respectively, can be achieved. Surfaces of the cylindrical EDM parts were examined using Scanning Electron Microscopy (SEM) to identify the macro-ridges and craters on the surface. Cross-sections of the EDM parts are examined using the SEM to quantify the sub-surface recast layers and heat-affected zones under various process parameters. This study has demonstrated that the cylindrical wire EDM process parameters can be adjusted to achieve either high material removal rate or good surface integrity and roundness.}, number={3}, journal={JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME}, author={Qu, J and Shih, AJ and Scattergood, RO}, year={2002}, month={Aug}, pages={708–714} } @article{shih_yan_2002, title={Synthesis of a single-loop, overconstrained six revolute joint spatial mechanism for two-position cylindrical rigid body guidance}, volume={37}, ISSN={["0094-114X"]}, DOI={10.1016/S0094-114X(01)00055-6}, abstractNote={The synthesis and analysis of a single-loop, overconstrained spatial mechanism with six binary links and six revolute joints for the guidance of a cylindrical rigid body between two positions are presented. The geometric constraints that make the spatial 6R mechanism movable are first introduced. Four features of the geometrical constraints of this mechanism are summarized to demonstrate its mobility and used for dimensional synthesis. Steps for mechanism dimensional synthesis are developed based on the descriptive and analytical geometry. The mechanism analysis based on analytical geometry is also presented. One of the advantages of this spatial mechanism is that the toggle position can be integrated into the synthesis. This is especially attractive in the synthesis of the wheel retract and twist mechanism for aircraft landing gears and the automated grinding wheel or tool changer for machine tools. A detailed example is used to illustrate the mathematical models for mechanism synthesis and analysis.}, number={1}, journal={MECHANISM AND MACHINE THEORY}, author={Shih, AJ and Yan, HS}, year={2002}, month={Jan}, pages={61–73} } @article{rhoney_shih_scattergood_ott_mcspadden_2002, title={Wear mechanism of metal bond diamond wheels trued by wire electrical discharge machining}, volume={252}, ISSN={["0043-1648"]}, DOI={10.1016/S0043-1648(02)00019-4}, abstractNote={The stereographic scanning electron microscopy (SEM) imaging was used to investigate the wear mechanism in wire electrical discharge machining (EDM) truing of metal bond diamond wheels for ceramic grinding. A piece of the grinding wheel was removed after truing and grinding to enable the examination of wheel surface and measurement of diamond protrusion heights using a SEM and stereographic imaging software. The stereographic SEM imaging method was calibrated by comparing with the profilometer measurement results. On the wheel surface after wire EDM truing and before grinding, some diamond grain protruding heights were measured in the 32 μm level. Comparing to the 54 μm average size of the diamond grain, this indicated that over half of the diamond was exposed. During the wire EDM process, electrical sparks occur between the metal bond and EDM wire, which leaves the diamond protruded in the gap between the wire electrode and wheel. These protruding diamond grains with weak bond to the wheel were fractured under a light grinding condition. After heavy grinding, the diamond protrusion heights were estimated in the 5–15 μm range above the wear flat. A cavity created by grinding debris erosion wear of the wheel bond could be identified around the diamond grain.}, number={7-8}, journal={WEAR}, author={Rhoney, BK and Shih, AJ and Scattergood, RO and Ott, R and McSpadden, SB}, year={2002}, month={Apr}, pages={644–653} } @article{rhoney_shih_scattergood_akemon_gust_grant_2002, title={Wire electrical discharge machining of metal bond diamond wheels for ceramic grinding}, volume={42}, ISSN={["1879-2170"]}, DOI={10.1016/S0890-6955(02)00056-1}, abstractNote={The application of cylindrical wire Electrical Discharge Machining (EDM) for profile truing of metal bond diamond wheels is presented. Instead of using the mechanical force to break the diamond and matrix in the grinding wheel, the wire EDM process uses the thermal energy or electrical sparks between the wire and rotating grinding wheel to remove the metal bond and form the wheel. The design and manufacture of a corrosion-resistant, precise spindle with the high-electrical current capability for wire EDM truing of grinding wheel is first introduced. Three truing configurations were designed to study effects of wire EDM process parameters and to investigate the level of form accuracy and corner radii achievable by the wire EDM truing of diamond wheels. Results show that the wire EDM process can efficiently generate the μm-scale precision form on the diamond wheels. The wheel, after truing, was used to grind the silicon nitride workpiece. Grinding forces and wheel wear rate were measured. In the beginning of the grinding, high wheel wear rate was identified. The subsequent wheel wear rate was considerably lower and stabilized.}, number={12}, journal={INTERNATIONAL JOURNAL OF MACHINE TOOLS & MANUFACTURE}, author={Rhoney, BK and Shih, AJ and Scattergood, RO and Akemon, JL and Gust, DJ and Grant, MB}, year={2002}, month={Sep}, pages={1355–1362} } @article{shih_2001, title={A new regulating wheel truing method for through-feed centerless grinding}, volume={123}, ISSN={["1087-1357"]}, DOI={10.1115/1.1366684}, abstractNote={A new regulating wheel truing method for through-feed centerless grinding is presented. In conventional regulating wheel truing systems, a single-point diamond tool is traversed across the regulating wheel in a straight line. The interference between the regulating wheel and workpiece exists. This interference problem, a main source of error in precision through-feed centerless grinding, is due to the radius of curvature of the regulating wheel and workpiece. A new concept for regulating wheel truing is developed to eliminate the interference problem. In this new truing system, the rotary diamond truing tool has the same size as the finished workpiece, locates at the same center-height of the workpiece, and moves across the regulating wheel in the direction parallel to axes of workpiece and grinding wheel. A mathematical model is developed to calculate the surface profile for the regulating contact and to study the curved line of contact between workpiece and regulating wheel. An example is used to illustrate the model and to demonstrate that the interference between regulating wheel and workpiece has been eliminated.}, number={2}, journal={JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME}, author={Shih, AJ}, year={2001}, month={May}, pages={319–324} } @article{shih_akemon_2001, title={Wear of the blade diamond tools in truing vitreous bond grinding wheels - Part I. Wear measurement and results}, volume={250}, ISSN={["0043-1648"]}, DOI={10.1016/S0043-1648(01)00610-X}, abstractNote={The wear of stationary blade diamond tools used to generate a precise and intricate form on the vitreous bond grinding wheel is presented. Two types of blade tools made of rod and particle diamond were used. A method to measure the wear of the blade diamond tool in the μm-scale range using the size difference of two parts ground before and after truing was introduced. Two sets of experiments with four truing feeds and four tool traverse speeds across the grinding wheel were conducted on the rod and particle blade diamond tools, respectively. Experimental results showed the wear rate of blade diamond tools was improved at higher truing feeds and traverse speeds due to the brittle fracture of the abrasive and vitreous bond.}, journal={WEAR}, author={Shih, AJ and Akemon, JL}, year={2001}, month={Oct}, pages={587–592} } @article{shih_clark_akemon_2001, title={Wear of the blade diamond tools in truing vitreous bond grinding wheels - Part II. Truing and grinding forces and wear mechanism}, volume={250}, ISSN={["1873-2577"]}, DOI={10.1016/S0043-1648(01)00611-1}, abstractNote={Truing and grinding forces and the wear mechanism of particle and rod diamond blade tools used to generate precise and intricate forms on rotating vitreous bond silicon carbide grinding wheels are presented. A Hall effect sensor was used to measure the change of grinding spindle power during truing and grinding. A signal processing procedure was developed to identify individual truing passes and to extract the average, peak-to-valley, and standard deviation of the variation of truing force for each pass. The truing force data and SEM micrographs of worn surfaces on blade tools reveal micro- and macro-fracturing of the diamond. The attritious and erosion wear of the diamond rod and particle, erosion of the metal bond, and pulling-out of the diamond particle are also identified. Grinding force data shows that, for the same truing parameters, a wheel trued by the rod diamond blade tool has higher grinding forces than one trued by a particle diamond blade tool.}, journal={WEAR}, author={Shih, AJ and Clark, WI and Akemon, JL}, year={2001}, month={Oct}, pages={593–603} } @article{shih_2000, title={An experimental investigation of rotary diamond truing and dressing of vitreous bond wheels for ceramic grinding}, volume={40}, ISSN={["0890-6955"]}, DOI={10.1016/S0890-6955(00)00022-5}, abstractNote={Experiments of rotary diamond truing and dressing of vitreous bond grinding wheels were conducted to investigate the effects of feed, speed ratio, and overlap ratio on cylindrical grinding of zirconia. The applications of ceramic engine components with complex and precise form and the lack of technology for precision truing of diamond grinding wheels have driven the need to study the use of vitreous bond CBN and SiC wheels for form grinding of ceramics. Truing and grinding forces and the roundness and surface finish of ground zirconia parts were measured. By varying truing process parameters, a wide range of surface finish and roundness could be achieved. Experimental results showed that wheels trued at speed ratio below −1.0 could grind parts with fine surface finish and good roundness. The analysis of truing and grinding results showed the trend of increasing grinding force at higher specific truing energy and better surface finish at higher grinding force. The lack of speed control of the direct–drive, variable–speed truing spindle was observed and its effect on the reverse of direction of truing force at positive speed ratios was studied.}, number={12}, journal={INTERNATIONAL JOURNAL OF MACHINE TOOLS & MANUFACTURE}, author={Shih, AJ}, year={2000}, month={Sep}, pages={1755–1774} } @article{shih_mcspadden_morris_grant_yonushonis_2000, title={High speed and high material removal rate grinding of ceramics using the vitreous bond CBN wheel}, volume={4}, ISSN={["1532-2483"]}, DOI={10.1080/10940340008945699}, abstractNote={Abstract High-speed (up to 127 m/s) and high material removal rate grinding experiments were conducted using a vitreous bond cubic boron nitride (CBN) wheel to investigate the effects of material removal rate, wheel speed, dwell time and truing speed ratio on cylindrical grinding of silicon nitride and zirconia. Experimental results show that operating the grinding wheel at a high surface speed can reduce grinding forces, enable high material removal rates, and achieve a higher grinding ratio (G-ratio). The material removal rate was increased to 9.6 and 7.6 mm3/s/mm for zirconia and silicon nitride, respectively, to explore the advantage of using high wheel speeds for cost-effective, high-material-removal-rate grinding of ceramics. Models for specific grinding force vs. the specific material removal rate and G-ratio vs. grinding wheel surface speed were developed based on the experimental results. Overall, this study showed that high grinding wheel surface speed is beneficial to the grinding of ceramics.}, number={1}, journal={MACHINING SCIENCE AND TECHNOLOGY}, author={Shih, AJ and McSpadden, SB and Morris, TO and Grant, MB and Yonushonis, TM}, year={2000}, pages={43–58} } @article{shih_lee_1999, title={Precision cylindrical face grinding}, volume={23}, ISSN={["0141-6359"]}, DOI={10.1016/S0141-6359(99)00008-2}, abstractNote={The mathematical models and experimental validations of precision cylindrical face grinding using a narrow ring superabrasive wheel are presented. The high pressure seal in diesel engine fuel systems demands the μm-scale form tolerance specifications and has driven the development of precision face grinding using the superabrasive wheel. Two mathematical models were developed: one was applied to predict the convex or concave face profile and another was used to simulate the abrasive trajectories, which become the cross-hatch grinding marks on the ground face. Cylindrical face grinding experiments were conducted. Experimental measurements of face profile and abrasive trajectories were used to validate the theoretical results. For high-pressure sealing surfaces, the height of face profile and grinding trajectories were two critical characteristics for design and manufacturing. Two design tools, a linear approximate solution for the profile height and an atlas for grinding trajectories, were developed to assist the selection of process parameters for the machine setup.}, number={3}, journal={PRECISION ENGINEERING-JOURNAL OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING}, author={Shih, AJ and Lee, NL}, year={1999}, month={Jul}, pages={177–184} } @article{tricard_gust_shih_1999, title={Systems approach for the ceramic thru-feed centerless grinding}, volume={3}, ISSN={["1091-0344"]}, DOI={10.1080/10940349908945690}, abstractNote={ABSTRACT An approach for simulation and production implementation of thru-feed centerless grinding of transformation toughened zirconia using vitreous bond diamond grinding wheels is presented. A set of grinding tests was designed and conducted to identify the effects of abrasive product (diamond grit size), work-material, and operational factors (stock removal, thru-feed rate, number of thru-feed passes and truing and dressing methods) on grinding performance. Evaluation parameters of surface finish, grinding forces and C-ratio were utilized to determine machine tool features. Very fine surface finishes, in the order of 0.05 to 0.1 u.m Ra range, could be achieved using vitreous bond micro-grit diamond wheels, without additional part processing. Such a level of surface finish on ground ceramics has traditionally been generated only by using resinoid bonded diamond wheels. These test results were used to design and manufacture a full-size composite or sandwiched diamond grinding wheel. This grinding wheel ...}, number={2}, journal={MACHINING SCIENCE AND TECHNOLOGY}, author={Tricard, M and Gust, DJ and Shih, AJ}, year={1999}, pages={201–219} } @article{tu_corless_gehrich_shih_1998, title={Experimental study of a precision, hydrodynamic wheel spindle for submicron cylindrical grinding}, volume={22}, ISSN={["0141-6359"]}, DOI={10.1016/S0141-6359(98)00003-8}, abstractNote={Abstract Hydrodynamic journal bearings have been widely used in various types of rotating machinery, ranging from heavy duty, high-impact applications, such as the crank shaft of an internal combustion engine and turbine rotor, to high-precision, light load applications, such as precision spindles in cylindrical grinding machines. Although extensive theoretical and experimental results have been presented for hydrodynamic bearings, the available literature seems to be limited for precision hydrodynamic bearing spindles. In this study, practical methods have been developed to quantify the performance of a hydrodynamic wheel spindle operating in the horizontal mode to produce precision parts with submicron roundness tolerance and very fine surface finish. These methods can easily and cost effectively be implemented on various machines in an actual production environment for effective predictive maintenance. The main experimental results show that the long-term drift of the spindle at steady state is less than 1 μm vertically and 0.2 μm horizontally, and the radial error motion of the spindle based on unfiltered data is less than 1.6 μm for all the speeds tested. It is also found that the shaft center position (vertical lift and horizontal shift) at the cold condition is substantially different from that in the steady-state warm condition. From the results, an optimal spindle speed is recommended.}, number={1}, journal={PRECISION ENGINEERING-JOURNAL OF THE AMERICAN SOCIETY FOR PRECISION ENGINEERING}, author={Tu, JF and Corless, M and Gehrich, MJ and Shih, AJ}, year={1998}, month={Jan}, pages={43–57} } @inproceedings{shih_yonushonis_grant_morris_mcspadden_1998, title={High speed and high material removal rate grinding of ceramics using the vitreous bond CBN wheel}, number={1998}, booktitle={ASPE 13th annual meeting, St. Louis, MO, Oct. 25-30, 1998}, author={Shih, A. J. and Yonushonis, T. M. and Grant, M. B. and Morris, T. O. and McSpadden, S. B.}, year={1998}, pages={25–30} } @article{shih_1998, title={Rotary truing of vitreous bond diamond grinding wheels using metal bond diamond disks}, volume={2}, ISSN={["1091-0344"]}, DOI={10.1080/10940349808945656}, abstractNote={Abstract Experiments on rotary truing of vitreous bond diamond grinding wheels were conducted to investigate the effects of truing speed ratio, type of diamond in the metal bond truing disks (synthetic versus natural), and diamond grit size in the grinding wheel on the wear of truing disk and on the cylindrical grinding of zirconia. Similar to G-ratio, a new parameter called D-ratio is defined to quantify the wear rate of the diamond truing disks. Experimental results show that, under the same truing condition, the truing disk with blocky, low friability synthetic diamond has a higher D-ratio than the truing disk with natural diamond. Diamond wheels trued by the disk with synthetic diamond also generate lower grinding force and rougher surface finish. High truing disk surface speed, 1.8 times higher than the surface speed of the grinding wheel, was tested and did not show any improvement in D-ratio. This study indicates that μm-scale precision form truing of the vitreous bond diamond wheel is difficult du...}, number={1}, journal={MACHINING SCIENCE AND TECHNOLOGY}, author={Shih, AJ}, year={1998}, pages={13–28} } @inproceedings{shih_yonushonis_grant_morris_mcspadden_1998, title={Vitreous bond CBN wheel for high speed grinding of ceramic and M2 steel}, number={1998}, booktitle={Transaction of 26th NAMRC (North American Manufacturing Research Conference), 1998}, author={Shih, A. J. and Yonushonis, T. M. and Grant, M. B. and Morris, T. O. and McSpadden, S. B.}, year={1998}, pages={195–200} }