Abstract: Milling strategies for machining dental ceramic materials are provided that reduce milling time while maintaining strength, accuracy and marginal integrity.

Abstract: A device for measuring the feed motion of a finishing belt includes a movable contact section for contacting the finishing belt, wherein a movement of the finishing belt can be transferred to the contact section, and a sensor device including a sensor and a reference section cooperating with the sensor, wherein the reference section or the sensor is motionally coupled with the contact section.

Abstract: To provide a manufacturing method which can adjust the lengths of a recording element and a reproducing element for enabling manufacture of high-quality magnetic head sliders. The manufacturing method comprises: a stacked-layer forming step which stacks magnetic heads on a substrate; a lapping step which cuts out a bar block having a plurality of connected magnetic head sliders, and polishes a flying surface; and a slider cutting step which cuts out individual magnetic head sliders from the bar block. The stacked-layer forming step forms a reproducing-element polish amount detecting sensor on a same layer as that of the reproducing element, and forms a recording-element polish amount detecting sensor on a same layer as that of the recording element. The lapping step carries out polishing based on each output value of the reproducing-element polish amount detecting sensor and the recording-element polish amount detecting sensor.

Abstract: A method in one embodiment includes forming an electric lapping guide layer; forming a write pole; forming a first gap layer over the write pole; masking a portion of the first gap layer for defining a window over the write pole and at least a portion of the electric lapping guide layer; and forming a bump over the write pole in the window. Additional methods and systems are presented.

Abstract: Processing a wafer using a double side grinder having a pair of grinding wheels. Warp data is obtained by a warp measurement device for measuring warp of a wafer as ground by the double side grinder. The warp data is received and a nanotopography of the wafer is predicted based on the received warp data. A grinding parameter is determined based on the predicted nanotopography of the wafer. Operation of the double side grinder is adjusted based on the determined grinding parameter.

Abstract: In a non-circular workpiece grinding machine, a proximity sensor is arranged to face a non-circular portion of a workpiece for sensing a maximum diameter portion of the non-circular portion to detect that the maximum diameter portion is rotating in a detection phase section when the work spindle is rotating in a low speed rotational phase region in which the work spindle is controlled by a numerical controller to rotate at a low speed. Abnormality judging means is provided for judging that an abnormal workpiece rotation is occurring when the maximum diameter portion of the non-circular portion is not detected by the proximity sensor in the state that the work spindle is rotating in the low speed rotational phase region.

Abstract: Provided is a gear matching device which performs gear matching to establish a rotational phase relationship between a grindstone (13) and a gear-shaped workpiece (W) in which the grindstone and the workpiece can mesh with each other, before gear machining is performed by causing the grindstone and the workpiece to mesh with each other, and by then relatively rotating the grindstone and the workpiece, the gear matching device including: a tail stock (16) which is supported to be movable in the axial direction of the workpiece, and by which the workpiece is pressed against a rotary table (18) to be rotatably held, the rotary table rotating the workpiece about the axis thereof; and a sensor (33) which is provided to the tail stock, and which faces the workpiece to detect the rotational phase thereof, when the tail stock holds the workpiece.

Abstract: Simultaneous double-side grinding of a plurality of semiconductor wafers involves positioning each wafer freely in a cutout of one of plural carriers which rotate on a cycloidal trajectory, wherein the wafers are machined between two rotating ring-shaped working disks, each disk having a working layer of bonded abrasive, wherein the form of the working gap between working layers is determined during grinding and the form of the working area of at least one disk is altered such that the gap has a predetermined form. The wafers, during machining, may temporarily overhang the gap. The carrier is optionally composed only of a first material, or is completely or partly coated with the first material such that during machining only the first material contacts the working layer, and the first material does not reduce the machining ability of the working layer.

Abstract: A grinding machine for grinding work pieces between centers, as well as for centerless grinding, features a drive for a grinding wheel and a drive for a regulating wheel. The work piece can be supported between the grinding wheel and the regulating wheel either between centers on a work piece axis or on a rest for centerless grinding. The driving axis of the regulating wheel and the work piece axis are parallel, and the wheels can be adjusted relative to the work piece independently of one another. The drive of the regulating wheel serves for driving the work piece while grinding between centers or for driving the work piece during centerless grinding. In addition, a means for measuring the contact pressure of the regulating wheel on the work piece is provided for grinding between centers. This means may consist, for example, of a pressure sensor.

Abstract: A substrate holding apparatus prevents a substrate from slipping out and allows the substrate to be polished stably. The substrate holding apparatus has a top ring body for holding and pressing a substrate against a polishing surface, and a retainer ring for pressing the polishing surface, the retainer ring being disposed on an outer circumferential portion of the top ring body. The retainer ring includes a first member made of a magnetic material and a second member having a magnet disposed on a surface thereof which is held in abutment against the first member.

Abstract: A polishing apparatus has a polishing pad, a top ring for holding a semiconductor wafer, and a vertical movement mechanism operable to move the top ring in a vertical, direction. The polishing apparatus also has a distance measuring sensor operable to detect a position of the top ring when a lower surface of the top ring is brought into contact with the polishing pad, and a controller operable to calculate an optimal position of the top ring to polish the semiconductor wafer based on the position detected by the distance measuring sensor. The vertical movement mechanism includes a ball screw mechanism operable to move the top ring to the optimal position.

Abstract: A method of grinding a ferrous roll may include: rotating a grinding wheel on a machine spindle to form a rotating grinding wheel; rotating a ferrous roll to form a rotating roll surface; bringing the rotating grinding wheel into contact with the rotating roll surface; traversing the rotating grinding wheel across an axial roll length of the rotating roll surface; and grinding the roll surface while varying at least one or both of a grinding wheel rotational speed and a said mill roll rotational speed at an amplitude of +/?1 to 40% with a period of 1 to 30 seconds.

Abstract: A visual feedback system and method for airfoil polishing is disclosed. In one aspect there is a system for providing visual feedback during a polishing operation of a workpiece. In this system there is a model having a representation of a desired shape of the workpiece. A scanning system generates a representation of a current shape of the workpiece while in-process during the polishing operation. A comparator compares the current shape of the workpiece to the desired shape of the workpiece. An illumination system highlights the workpiece with visible light during the polishing operation. The highlighting of the workpiece with visible light is a function of the comparison between the current shape and the desired shape. The illumination system highlights a portion of the workpiece that needs additional polishing to conform to the desired shape.

Abstract: The invention relates to an ophthalmic machining machine comprising machining means and means for supporting a blank. The invention is characterised in that the machine is capable of transferring marks to said blank that can be identified by monitoring means for repositioning the blank on said supporting means after machining the opposite surface. The invention also relates to a workholding tool. The invention is characterised in that said supporting means are mounted on a bearing surface, which is oblique in relation to a surface of a carriage, by depression of an opening surrounded by an O-ring seal and a fixed bearing. The invention also relates to a machining method according to which the markings are transferred to a blank, the position of said markings is assessed by monitoring means which position machining means for the machining process, and each surface of the resulting lens is polished with polishing means.

Abstract: A wafer polishing apparatus includes a polishing tape extending between two guide rollers, a first surface of the polishing tape contacting a surface of a wafer to be polished, a polishing head including a pusher pad, the pusher pad adapted to push the polishing tape against the surface of the wafer to be polished, a color image sensor adjacent to the polishing tape, the color image sensor being adapted to detect a color image of the polishing tape and to output a signal corresponding to the detected color image, and a controller connected to the color image sensor, the controller being adapted to receive the signal output from the color image sensor and to determine when a color of the color image detected by the color image sensor changes, a change in the color image indicating a polishing end point.

Abstract: In the method of precisely polishing a work, torque of a sun gear and an internal gear are kept constant and a load applied to a carrier is reduced and maintained. The method comprises the steps of: changing a rotational speed of at least one of the sun gear, the internal gear, an upper polishing plate and a lower polishing plate; measuring rotation torque of a driving motor of at least one of the sun gear and the internal gear; detecting the minimum rotation torque measured in the measuring step; and adjusting the rotational speed of at least one of the sun gear, the internal gear, the upper polishing plate and the lower polishing plate so as to make the rotation torque thereof equal to the minimum rotation torque or running rotation torque, the running rotation torque being greater by a prescribed value than the minimum rotation torque.

Abstract: A polishing apparatus is provided for polishing wafers at a high yield rate even if roll-off exists. The polishing apparatus polishes a wafer by applying a pressure between a polishing member (polishing pad) 201 and the wafer held by a holding member (top ring) 52 and moving the polishing member relative to the wafer. The polishing apparatus includes a top ring 52 for holding the wafer, a pressure adjusting mechanism for adjusting a supporting pressure with which the wafer is supported on a supporting surface by a retainer ring, and a control unit for controlling the pressure adjusting mechanism to bring the supporting pressure to a desired pressure based on a roll off quantity of the wafer. The top ring comprises an air bag 202 for pressing the wafer against the polishing pad, a retainer ring which surrounds the wafer, and an air bag for pressing the retainer ring.

Abstract: A precision machining method enabling grinding with high accuracy is provided. The method includes a first step of producing an intermediate ground workpiece by roughly grinding a workpiece (a) with a diamond grinding wheel (b), and a second step of producing a final ground workpiece by grinding the intermediate ground workpiece with a grinding wheel for CMG. In the first step, feed of the rotator (6b) and the base (3) is controlled in multiple stages with different feed speeds according to control based on the amount of movement, and in the second step, movement of the rotator (6b) and the base (3) is controlled with a constant pressure or in multiple stages having different constant pressures.

Abstract: An apparatus includes: a first layer having a near field transducer positioned in a waveguide cladding; a second layer having a magnetic pole piece; a third layer including a solid immersion mirror; a first lapping guide positioned in the first layer; a second lapping guide positioned in the second layer; and a third lapping guide positioned in the third layer.

Abstract: An apparatus for grinding a threaded portion of a workpiece, is provided. The threaded portion has a spiral groove formed therein. The apparatus includes a motor, a grinding cord, a detector and a controller. The motor has a rotary portion for rotating the threaded portion of the workpiece about an axis. The grinding cord is configured for being looped around the threaded portion of the workpiece with a middle part thereof engagingly received in a given portion of turns of the spiral groove for grinding the thread portion of the workpiece. The detector is for detecting a rotating cycle of the rotary portion. The controller is communicatively coupled to the detector for controlling the rotary portion to selectively rotate in a first rotating direction or in a reverse second rotating direction based on the received signal from the detector.

Abstract: A cut section checking/aligning unit simultaneously checks cut sections of unit liquid crystal display panels that are separated from within first and second base substrates and aligns the unit liquid crystal display panels to a reference position. A grinding unit grinds edges of the unit liquid crystal display panels. The cut section checking/aligning unit and the grinding unit are integrated within a grinding device.

Abstract: A step portion for mounting a row bar is provided at a table stepping down from the face of the table, and by lowering a pair of hooks crossing over the step portion in its width direction, a row bar held by the hooks is mounted on the step portion. While interposing the row bar mounted on the step portion between a pair of hooks and a side face of the step portion, the side in longitudinal direction of the row bar and the bottom face thereof are butted to the bottom face and the standing up side face of the step portion to position two axes of the row bar among XYZ directions, successively, positioning of the row bar in one remaining direction along longitudinal direction of the row bar mounted on the step portion is performed by moving the table in the one remaining axial direction.

Abstract: Grinding machine with a machine bed, with a tool carriage that is linearly movable on the machine bed in a Y-axis, with a tool spindle, which is mounted in the tool carriage so as to rotate around an X-axis that is perpendicular to the Y-axis, and which can be rotationally driven, with an X-carriage that is linearly movable on the machine bed in the X-axis, with a Z-carriage that is linearly movable on the X-carriage with a Z-axis that is perpendicular to the X-axis and the Y-axis, and with a work piece jig, which is arranged on the Z-carriage so as to pivot around a B-axis, which is parallel to the Y-axis, and which is capable of rotating around its A-axis, which is perpendicular to the B-axis.

Abstract: An apparatus and method for grinding a workpiece by rotating the workpiece about a rotational axis, rotating a cylindrical grinding wheel about a rotational axis being parallel to the rotational axis of the workpiece, moving the grinding wheel relative to the workpiece at least in one of a first direction being perpendicular to the rotational axis of the workpiece for grinding the workpiece at a cylindrical surface of the grinding wheel and a second direction being parallel to the rotational axis of the workpiece for grinding the workpiece at an end surface of the grinding wheel being perpendicular to the rotational axis of the grinding wheel, and by superimposing a vibration signal including a plurality of frequency components to a driving signal outputted to one of a workpiece rotating means for rotating the workpiece and a grinding wheel rotating means for rotating the grinding wheel.

Abstract: A system and a method of operating a chemical mechanical polishing (CMP) system comprises a slurry delivering unit configured for locally varying the supply of slurry while polishing the substrate. To this end, the slurry delivering unit may comprise at least one slurry outlet over a polishing pad of the CMP system, wherein the at least one slurry outlet is controllably movable to distribute slurry over the polishing pad.

Abstract: A manufacturing method of a spectacle lens improving a manufacturing yield and a production efficiency is provided. The manufacturing method of the spectacle lens in which necessary information for a frame machining of a spectacle lens (progressive-power lens 20) including spectacle rim related information is obtained, and both surfaces of a convex surface and a concave surface are edge/polish machined from a spectacle lens blanks.

Abstract: A polishing apparatus polishes wafers at a high yield rate even if roll-off exists. The polishing apparatus polishes a wafer by applying a pressure between a polishing member (polishing pad) and the wafer held by a holding member (top ring) and moving the polishing member relative to the wafer. The polishing apparatus includes a top ring for holding the wafer, a pressure adjusting mechanism for adjusting a supporting pressure with which the wafer is supported on a supporting surface by a retainer ring, and a control unit for controlling the pressure adjusting mechanism to bring the supporting pressure to a desired pressure based on a roll off quantity of the wafer. The top ring comprises an air bag for pressing the wafer against the polishing pad, a retainer ring which surrounds the wafer, and an air bag for pressing the retainer ring.

Abstract: A polishing apparatus is provided for polishing wafers at a high yield rate even if roll-off exists. The polishing apparatus polishes a wafer by applying a pressure between a polishing member (polishing pad) 201 and the wafer held by a holding member (top ring) 52 and moving the polishing member relative to the wafer. The polishing apparatus includes a top ring 52 for holding the wafer, a pressure adjusting mechanism for adjusting a supporting pressure with which the wafer is supported on a supporting surface by a retainer ring, and a control unit for controlling the pressure adjusting mechanism to bring the supporting pressure to a desired pressure based on a roll off quantity of the wafer. The top ring comprises an air bag 202 for pressing the wafer against the polishing pad, a retainer ring which surrounds the wafer, and an air bag for pressing the retainer ring.

Abstract: A method for grooving or counter-beveling the periphery of an opthamalic lens in a grinding machine is provided. The grinding machine includes a lens support with a mechanism configured to rotate the lens about a first axis, a grooving or counter-beveling wheel rotatable about a second axis which can be tilted relative to the first axis, and a mechanism to adjust the angle of tilt of the second axis relative to the first axis. Initially, a profile for the groove is determined. A single treatment angle corresponding to the profile is calculated, and the angle of tilt of the second axis is adjusted to the value of the single treatment angle. A groove or counter-bevel is ground into the periphery of the lens with the angle of tilt remaining constant throughout the grinding.

Abstract: Milling strategies for machining dental ceramic materials are provided that reduce milling time while maintaining strength, accuracy and marginal integrity.

Abstract: A precision machining apparatus is structured such that a feed-screw mechanism and an actuator are mounted on a second mount which supports a rotating device that rotates a wheel, and grinding is performed while appropriately adjusting the amount of movement of the second mount in a rough grinding stage through an ultra-precision grinding stage. A posture control device is interposed between a first mount and a rotating device that rotates a grinding target body. The thickness and evenness of the grinding target body are measured by an optical probe and the measurement results are sent to a computer. A feedback command is then sent to the posture control device to reduce the difference between target values and the measurement values and posture control is performed accordingly.

Abstract: A method of processing a semiconductor wafer using a double side grinder of the type that holds the wafer in a plane with a pair of grinding wheels and a pair of hydrostatic pads. The method includes measuring a distance between the wafer and at least one sensor and determining wafer nanotopology using the measured distance. The determining includes using a processor to perform a finite element structural analysis of the wafer based on the measured distance.

Abstract: A method and apparatus for removing a coating having an irregular surface configuration that includes mapping the irregular surface configuration, and using the mapping determination in controlling the operation of an abrasive water jet to provide increased material removal rates at the higher points in the irregular surface and decreased material removal rates at the lower points, and thereby even out the surface configuration of the coating. The method and apparatus also includes using a detection device for detecting the presence or absence of an element that is unique to a layer of a coating, and using the detection determination in controlling the operation of the abrasive water jet to stop material removal of the coating when the detection device determines there is an absence of the unique element.

Abstract: A polishing pad can include a first layer and a second layer. The first layer can have a first polishing surface and a first opening. The second layer can have an attaching surface and a second opening substantially contiguous with the first opening. The polishing pad can further include, a pad window lying within the first opening. The pad window can include a second polishing surface. When the pad would be attached to a platen, the first and second polishing surfaces can lie along a same plane, and an opposing surface of the pad window can abut an exterior surface of a platen window. In another aspect, a polishing apparatus can include an exterior surface of a platen window abutting the polishing pad. In still another aspect, a process of polishing can include polishing a workpiece such that the pad window contacts the workpiece and the platen window simultaneously.

Abstract: Provided is a substrate polishing apparatus that includes a polishing unit and a pad supporting member. The polishing unit includes a polishing pad polishing a substrate seated on a substrate supporting member, and a pad driving member moving the polishing pad. The pad supporting member is disposed at a side of the substrate supporting member to support a portion of a polishing surface the polishing pad without contacting the substrate when an edge of the substrate seated on the substrate supporting member is polished. Accordingly, the substrate polishing apparatus prevents the polishing pad from being inclined to the outer side of a substrate while an edge of the substrate is polished, thereby improving polishing efficiency and preventing the breakage of a substrate during a polishing process.

Abstract: The present invention relates to a method and system (100) for ensuring a predetermined level of accuracy of a parallel orientation of a tool tip surface (112) with respect to a work piece holder (110) surface (108) of an assembly device. A grinding plate (130) is provided onto the work piece holder surface and a grinding material is deposited thereupon. The tool tip (106) is then moved to a predetermined distance above the grinding plate and moved relative to the grinding plate in a plane oriented substantially parallel to the grinding plate top surface (128). At a plurality of predetermined locations on the tool tip surface a distance between the tool tip surface and the work piece holder surface is measured and a level of accuracy of a parallel orientation of the tool tip surface with respect to the work piece holder surface is determined in dependence upon the measured distances.

Abstract: A lapping tool for lapping a wafer section in a well controlled manner, has a head with an actuator for bending the row tool, and a force multiplier coupled between the actuator and row tool to multiply the force generated by the actuator for application of greater bending force to the row tool than can be generated by the actuator. Furthermore, at least two actuators, which are controlled together, simultaneously apply force to one force multiplier, so as to further increase bending force. The increase in available force permits the use of a row tool of a ceramic or other material that is substantially stiffer than stainless steel, such as a row tool having a coefficient of thermal expansion that is substantially similar to that of the rowbar itself. The tool further includes structures for tilting or otherwise orienting the wafer section relative to the lapping plate.

Abstract: The present invention relates to a substrate polishing apparatus and a substrate polishing method for polishing a substrate such as a semiconductor wafer to a flat finish. The substrate polishing apparatus includes a polishing table (100) having a polishing surface (101), a substrate holder (1) for holding and pressing a substrate (W) against the polishing surface (101) of the polishing table (100), and a film thickness measuring device (200) for measuring a thickness of a film on the substrate (W). The substrate holder (1) has a plurality of pressure adjustable chambers (22 to 25), and pressures in the respective chambers (22 to 25) are adjusted based on the film thickness measured by the film thickness measuring device (200).

Abstract: A substructure in which a plurality of pre-head portions are aligned in rows is to be cut later so that the pre-head portions are separated from one another. A surface formed by cutting the substructure is lapped to form medium facing surfaces. The substructure includes a plurality of sensors that respectively show individual sensor values corresponding to values of a plurality of different parameters each of which has an influence on characteristics relating to the pole layer and each of which depends on the position of the medium facing surface. The individual sensor values are resistance values each of which varies according to the position of the medium facing surface. The plurality of sensors are electrically connected to each other to form a composite sensor that shows a composite sensor value, which is a resistance value that depends on the resistance values of the plurality of sensors.

Abstract: A system for polishing a semiconductor wafer. The system includes a polishing apparatus having a rotatable polishing pad for polishing the wafer. A dressing apparatus is mounted adjacent the polishing pad for dressing the polishing pad. The dressing apparatus includes a dressing member engageable with the polishing pad. A cleaning apparatus is mounted adjacent the polishing pad for removing particulate and chemicals from the polishing pad. The system includes a controller for controlling the dressing apparatus and the cleaning apparatus.

Abstract: A dressing apparatus for dressing a polishing pad includes a dressing member engageable with the polishing pad. The dressing apparatus is adapted to change the amount of force exerted by the dressing member on the polishing pad as the dressing member moves radially along the polishing pad. A controller for controlling the dressing apparatus has pre-programmed recipes that are selectable based on the radial profile of a measured polished wafer.

Abstract: The present invention relates to an apparatus (10) for processing and measuring workpieces, in particular plate-shaped or cylindrical workpieces, which are provided with cutting teeth (S), with a machine base (12), a processing and measuring device (14) which can be moved relative to the machine base (12), and a workpiece positioning device (16) which can be moved relative to the machine base (12), wherein the processing and measuring device (14) has a pivoting head (26) which can be moved relative to the machine base (12) such that it can pivot about a pivot axis (E1), wherein a processing tool (28) and a measuring probe (30) are provided on the pivoting head (26). In this case provision is made for the processing tool (28) to project from one side of the pivoting head (26) and for the measuring probe (30) to project from the side of the pivoting head (26) which is opposite with respect to the pivot axis (E1).

Abstract: In one aspect of the present invention, an outer diameter (O.D.) centerless grinding machine for use in grinding a diamond workpiece has a grinding wheel positioned parallel to a regulating wheel which is adapted to press a cylindrical workpiece into the grinding wheel as the regulating wheel rotates. Electronic equipment may be adapted to adjust a pressure of the regulating wheel against the grinding wheel. Also, a carrier may be adapted to house the workpiece, the carrier being attached to a translation mechanism adapted to move the carrier between the wheels such that the workpiece is in contact with both wheels.

Abstract: A polishing apparatus makes it possible to polish and remove an extra conductive film while preventing the occurrence of erosion and without lowering of the throughput. The polishing apparatus includes: a polishing table having a polishing surface; a top ring for holding a workpiece having a surface conductive film, and pressing the conductive film against the polishing surface to polish the conductive film; an optical sensor for monitoring the polishing state of the conductive film by emitting light toward the conductive film of the workpiece held by the top ring, receiving reflected light from the conductive film, and measuring a change in the reflectance of the reflected light; and a control section for controlling a pressure at which the workpiece is pressed on the polishing surface.

Abstract: A system for lapping a head on a wafer including at least one head each having an electrical lapping guide (ELG), a plurality of wafer contacts in electrical communication with the ELG, and a closure formed thereon defining a slot in which the wafer contacts are positioned, the system comprising a lapping cable coupled to a testing device, the lapping cable including a plurality of lapping cable contacts extending outwardly therefrom; wherein the lapping cable contacts are removably positionable in electrical communication with the wafer contacts during a lapping process. Additional systems and methods are also presented.

Abstract: Some problems related to processing workpieces are presented along with solutions to one or more of the problems. One embodiment of the invention comprises a sensor apparatus for collecting data representing one or more process conditions used for processing a workpiece. Another embodiment of the present invention is a combination comprising a sensor apparatus and a process tool for applications such as chemical mechanical planarization of workpieces and chemical mechanical polishing of workpieces.

Abstract: Head elements are formed on a wafer to suppress deterioration in pinning strength of a pinned layer, which is caused by ESD generated during air bearing surface polishing of a thin film magnetic head. The wafer is cut into rovers in each of which are connected head elements. Rover air bearing surfaces are polished until an MR elements attain a predetermined height. A final polishing step finishes air bearing surfaces by applying an electroconductive polishing liquid to achieve a predetermined shape and surface roughness with high accuracy. A pinning defect occurrence rate is reduced by suppressing deterioration in pinning strength of a pinned layer of a read element. To achieve this, a specific resistance of the electroconductive polishing liquid is controlled to 5 G?·cm or less. A shallow rail and a deep rail are formed on the air bearing surfaces, and the rover is cut into thin film magnetic heads.

Abstract: Apparatus and methods are provided for polishing a substrate with a polishing tape. The polishing tape includes a first surface adapted to contact a substrate; and a second surface, wherein at least one of the first and second surfaces include a feature adapted to indicate an end condition. Numerous other aspects are provided.

Abstract: The lapping of a slider is controlled based on an amplitude of a readback signal which is produced from an externally applied magnetic field. A lapping plate is used to lap a slider which includes at least one magnetic head having a read sensor. During the lapping, a coil produces a magnetic field around the slider and processing circuitry monitors both a readback signal amplitude and a resistance of the read sensor. The lapping of the slider is terminated based on the monitoring both the readback signal amplitude and the resistance. Preferably, the lapping of the slider is terminated when the resistance is within a predetermined resistance range and the readback signal amplitude is above a predetermined minimum amplitude threshold or reaches its peak value. Asymmetry can also be measured in the described system, where the lapping process is terminated based on asymmetry as well as resistance and amplitude measurements.

Abstract: A method and apparatus for_cutting a profile in a workpiece, such as a turbine disk, without cracking the parent material which includes providing a grinding wheel having a ceramic grinding surface formed with an optimized grain material and grain spacing to produce large chips that are easily removed from the workpiece, applying the grinding wheel to the workpiece at a predetermined material removal rate, and increasing the material removal rate when the burning point is recognized at the surface of the workpiece by the grinding action of the grinding wheel, and delivering coolant/lubricant to the workpiece during the grinding operation.