Abstract: In a method of manufacturing a liquid-cooling cold plate, cast molding is performed after embedding a metal pipe for supplying a cooling liquid inside a casting mold. Fixing brackets to be attached to the metal pipe is provided to maintain a positional relationship between a plurality of portions of the metal pipe embedded in the casting mold. The casting molding is performed by pouring molten metal into the casting mold while the fixing metal parts are attached to the metal pipe.

Abstract: The invention is directed to the interventionless activation of wellbore devices using dissolving and/or degrading and/or expanding structural materials. Engineered response materials, such as those that dissolve and/or degrade or expand upon exposure to specific environment, can be used to centralize a device in a wellbore.

Abstract: A lining for a metallurgical vessel is configured to have an engineered porosity. The lining contains a plurality of regions, each extending in a primary plane of the lining, each region having a differing value of total pore or perforation area as measured in a primary plane of the lining. The lining may be used to form part or all of the working surface of the floors or walls of the vessel. In casting use the lining produces an oxidation buffering layer at an interphase of metal melt extending from the interface between metal melt and the walls and floor of the metallurgical vessel, such that when in casting use, the metal flow rate in said oxidation buffering layer is substantially nil, and the concentration of endogenous inclusions, in particular oxides, in said oxidation buffering layer is substantially higher than in the bulk of the metal melt.

Abstract: Provided is a silver-coated copper powder that has a dendritic shape, that ensures excellent conductivity as a result of having an increased number of points of contact when silver-coated dendritic copper particles are in contact, prevents aggregation, and that can be suitably used in a conductive paste, and an electromagnetic wave shield. The silver-coated copper powder comprises amassed dendritic copper particles having a linearly grown main trunk and a plurality of branches branching from the main trunk. The surface of the copper particles is coated with silver. The main trunk and the branches of the copper particles have a flat plate shape in which the average cross-sectional thickness is more than 1.0 ?m but no more than 5.0 ?m. The silver-coated copper powder has a flat plate shape configured from a layered structure of one layer or a plurality of stacked layers. The average particle size (D50) is 1.0-100 ?m.

Abstract: There is provided a copper powder containing an organic compound containing carbon and nitrogen. The powder has a ratio of carbon content PC (mass %) to specific surface area SSA (m2/g), PC/SSA, of 0.005 to 0.1 and a ratio of nitrogen content PN (mass %) to specific surface area SSA (m2/g), PN/SSA, of 0.001 to 0.05. The organic compound preferably contains two or more of nitrogen atom per molecule and is preferably capable of forming a five-membered ring complex with copper. The organic compound preferably includes one or more of dimethyl glyoxime, ethylenediamine, and polyethyleneimine.

Abstract: A polycrystalline tungsten compact, having high density and a fine grain structure is produced by: preparing a raw material powder made of W particles, a raw material powder where W powder and an alloy particle powder of one or more selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and Mn are blended, or a green compact thereof; inserting them in a pressure sintering apparatus; and sintering them in a state where a pressing of 2.55-13 GPa is loaded on the raw material powders or the green compacts at 1200° C. to a melting point. A relative density of the compact is 99% or more, a porosity of the compact measured in an arbitrary cross section of the compact is 0.2 area % or less, an average crystal grain size is 50 ?m or less, and an average aspect ratio of crystal grains is 1 to 2.5.

Abstract: An additive manufacturing device utilizing an electron beam and laser integrated scanning comprises: a vacuum generating chamber (1); a worktable means having a forming region at least provided in the vacuum generating chamber (1); a powder supply means configured to supply a powder to the forming region; an electron-beam emission focusing and scanning means (6) and an laser-beam emission focusing and scanning means (7) configured in such a manner that a scanning range of the electron-beam emission focusing and scanning means (6) and a scanning range of the laser-beam emission focusing and scanning means (7) cover at least a part of the forming region; and a controller configured to control the electron-beam emission focusing and scanning means (6) and the laser-beam emission focusing and scanning means (7) to perform a powder integrated-scanning and forming treatment on the forming region.

Abstract: An apparatus (1) for manufacturing of three-dimensional objects (2), especially SLM or SLS apparatuses (selective laser melting apparatus or selective laser sintering apparatus), significantly comprising a construction room (4) arranged in a housing (3) of the apparatus (1).

Abstract: The present disclosure relates to a method and system for manufacturing a multi-lobed helical rotor. The method for manufacturing a multi-lobed helical rotor may comprise mixing one or more powdered metals, compacting a mixture of one or more powdered metals to form a solid metal piece, sintering the solid metal piece, and polishing the solid metal piece. The system may comprise a positive displacement pump, which may comprise a casing, a multi-lobed helical rotor disposed in the casing, wherein the multi-lobed helical rotor comprise sintered powdered metals, an inlet to the casing, and an outlet leading from the casing.

Abstract: A heat-treating method for compact includes a compacting step of forming a compact by compacting a soft magnetic powder together with a compacting assistant, the soft magnetic powder being a collection of coated particles that are soft magnetic metal particles having a surface coated with an insulation coating, and a heat-treatment step of heat-treating the compact, the heat-treatment step including a first heat-treatment substep of performing heat treatment at a temperature in a decomposition temperature range of the compacting assistant, and a second heat-treatment substep of performing heat treatment at a temperature at which distortion of the soft magnetic powder in the compact is removed and which is higher than the temperature of the first heat treatment.

Abstract: A method of making an engine system component is disclosed. The method may include loading a first metal-based material and a second metal-based material into an extrusion chamber. The first metal-based material may concentrically surround the second metal-based material, and the first metal-based material may have at least one of a thermal property and a wear resistance different than the second metal-based material. The method may additionally include forming an extrudate by simultaneously passing the first metal-based material and the second metal-based material through a die. The first metal-based material of the extrudate may be metallurgically bonded to the second metal-based material of the extrudate. The method may also include forging the extrudate.

Abstract: In a method of manufacturing metal powders in a continuous type, metal is heated at a temperature greater than a melting point to form a liquid phase metal, and the liquid phase metal and an emulsion carrier, which is emulsified without reacting with the liquid phase metal, are supplied into a container, and the liquid phase metal and the emulsion carrier are emulsified through Taylor flow to form an emulsion solution. The emulsion solution is discharged from the container, and then, the emulsion solution is cooled at a temperature smaller than the melting point to selectively solidifying the liquid phase metal in the emulsion solution to form the metal powders.

Abstract: A machine tool includes one tip arranged on the spindle at a position that faces the table, a cutting edge position storing unit that stores therein multiple measured values that are obtained by performing measurement of the position of the tip at least two times in a state where the spindle is set at at least one phase and the tip is positioned at an identical point, a spindle tilt angle calculating unit that calculates a tilt angle of the spindle with respect to an XY-plane, based on the multiple measured values, and a coordinate system rotation unit that rotates the XY-plane about at least one of X-axis and Y-axis, based on the tilt angle of the spindle calculated by the spindle tilt angle calculating unit.

Abstract: A polycrystalline diamond body contains diamond particles, the diamond particles have a mean particle size of 50 nm or less, and a crack initiation load is 10 N or more as measured in a fracture strength test by pressing a diamond indenter D with a tip radius Dr of 50 ?m against a surface of the polycrystalline diamond body at a load rate F of 100 N/min. Accordingly, a polycrystalline diamond body that is tough and has a small diamond particle size, a cutting tool, a wear-resistant tool, a grinding tool, and a method for producing the polycrystalline diamond body are provided.

Abstract: A tool chuck for clamping a tool in a machine tool, having a base body and a sleeve part protruding therefrom, which sleeve part forms a tool holder for fixing a tool shaft in a frictional, nonpositive fashion; a cavity in which a vibration damping component is accommodated is provided in the tool chuck.

Abstract: Some embodiments of a device comprise a collet, a holder that has a proximal end that is configured to hold the collet and a distal end that has a cavity, and a holder sleeve at the proximal end of the holder. Also, the holder sleeve is configured to increase a grip of the collet, the collet and the holder define an opening that is configured to receive a pin, the opening extends from the cavity through a center of the holder and a center of the collet along a longitudinal axis of the collet and a longitudinal axis of the holder, and the cavity of the holder is wider than the opening.

Abstract: A tool unit for performing a chamfering operation on a workpiece is disclosed. The tool unit includes a body, a plunger, at least one insert holder, and at least one cutter insert. The body includes a bore, and the plunger is movably positioned within the bore. The insert holder is coupled to the body and is in engagement with the plunger. The cutter insert is coupled to the at least one insert holder. The cutter insert includes a cutting edge adapted to be positioned at a cutting angle relative to the workpiece, and the cutting angle is varied relative to the workpiece upon a movement of the plunger within the bore.

Abstract: Systems and methods for maintaining a kiosk that scans and/or duplicates keys are provided. In some embodiments, the system comprises: a kiosk comprising: a key slot disposed in a surface of the kiosk; a key scanning device; a key scanning housing mounted behind the key slot, wherein the key scanning device is positioned in relation to the key scanning housing to facilitate capturing information about the key inserted in the key slot; a vacuum cleaner; a hose connecting the vacuum cleaner and the key scanning housing; and at least one hardware processor that is programmed to: determine that the key is to be scanned; and cause the vacuum cleaner to run creating a partial vacuum in the vicinity of the key scanning housing.

Abstract: Systems and methods for maintaining a kiosk that scans and/or duplicates keys are provided. In some embodiments, the system comprises: a kiosk comprising: a key slot disposed in a surface of the kiosk; a key scanning device; a key scanning housing mounted behind the key slot, wherein the key scanning device is positioned in relation to the key scanning housing to facilitate capturing information about the key inserted in the key slot; a vacuum cleaner; a hose connecting the vacuum cleaner and the key scanning housing; and at least one hardware processor that is programmed to: determine that the key is to be scanned; and cause the vacuum cleaner to run creating a partial vacuum in the vicinity of the key scanning housing.

Abstract: In a formed end mill, a peripheral cutting edge has a smaller-diameter cutting part and a larger-diameter cutting part. An imaginary line obtained by lining up a deepest point of a flute bottom of a chip discharge flute, which appears in a cross-sectional view perpendicular to an axis of an end mill body, in an extending direction of the chip discharge flute is defined as a virtual flute bottom line. A flute helix angle, which is formed between the virtual flute bottom line and the axis, in a side view when the end mill body is seen from a radial direction orthogonal to the axis, is 0 degrees or more at a distal end part of the chip discharge flute in the axial direction, and increases gradually from the distal end part toward a posterior end in the axial direction.

Abstract: Provided is an apparatus for preparing wire rope having a stand; a first cross-member; a second cross-member; a first clamp arm; a second clamp arm; a first clamp; a second clamp; an adjustment wheel; an adjustment screw; and an adjustment gear; wherein the second cross-member is at least partially contained within the first cross-member; wherein the first clamp is disposed at the distal end of the first clamp arm, the second clamp is disposed at the distal end of the second clamp arm, and wherein the first and second clamp arm are spaced from each other; and wherein the distance between the first and second clamp arm is adjustable. Also provided is a method of use for the same.

Abstract: The invention relates to a chop saw for a cutting machine, having an axis of rotation (2) and comprising a circular first sawtooth disk (4) and a first carrier (3) holding the first sawtooth disk (4), wherein the first saw tooth disk (4) has a plurality of sawteeth (5) over the circumference thereof and/or on the flat surfaces thereof, and wherein the first carrier (3) is symmetrical along the axis of rotation (2), and wherein the first carrier (3) has, on a first carrier surface (7), a retaining mandrel (9) for holding the chop saw (1) in a machine chuck of the cutting machine, and wherein the first sawtooth disk (4) is positioned on a second carrier surface (8) of the first carrier (3), which faces away from the first carrier surface (7), and wherein the chop saw (1) has a second sawtooth disk (11), which is arranged parallel to the first sawtooth disk (4).

Abstract: A method for producing gears, wherein in a first step a set of teeth is formed by means of a skiving wheel rotationally driven by a tool spindle in a workpiece gear rotationally driven synchronously thereto by a workpiece spindle, wherein the workpiece spindle and the tool spindle are at an axis intersection angle to each other and the advancement occurs in the tooth-flank extension direction, and wherein in a second step at least some teeth of the set of teeth are machined by means of a tooth-machining tool. A combined tool is used, in the case of which the toothmachining tool and the skiving wheel are fixedly connected to each other. Between the two steps, the combined tool remains connected to the tool spindle and the workpiece gear remains connected to the workpiece spindle. Between the two steps, merely the relative position of the tool spindle in relation to the workpiece spindle and the rotational speed ratio of the two spindles are changed.

Abstract: A device and method for broken tap removal are provided herein. The tap includes a circular longitudinal cavity used for removal and coolant transport. A tap removal tool that is pre-formed to fit the tap's center hole and provides at least three points of contact with the broken tap portion to allow for ease in removing the broken tap.

Abstract: A wire electrical discharge machine which performs electrical discharge machining on a workpiece, includes: a worktable on which the workpiece is placed; a placement area detector that divides the top surface of the worktable into multiple areas and detects the areas where the workpiece is placed; a placement time measuring unit that measures placement time for which the workpiece is placed on each of the areas detected by the placement area detector; and a cumulative time storage that adds up the placement times measured by the placement time measuring unit for each of the areas as a cumulative time for the area.

Abstract: Apparatuses, systems, and/or methods relate to a welding system that provides a field former for use in welding applications. The welding system includes a welding torch that includes one or more coil windings through which flows current that forms a magnetic field. The magnetic field is concentric to the tool center point. An arc is formed between the electrode and a workpiece. The magnetic field forces the arc in a center of the welding torch or the one or more coiled windings.

Abstract: The invention described herein generally pertains to a system and method related to an engine driven welding device that includes a first brushless generator component configured to produce a first electrical current for use with a welding operation and a second brushless generator component configured to produce a second electrical current for use as auxiliary power. The first brushless generator component can be a permanent magnet generator and the second brushless generator component can be an asynchronous generator, each being coupled to a shaft of an engine within the engine driven welding device. A portion of the first electrical current produced can be fed into the second brushless generator component to act as an exciter, wherein the frequency of the portion of the first electrical current can be matched to the frequency of the second brushless generator component.

Abstract: Systems and methods are disclosed that provides a helical wire for use in welding applications. A torch can be adapted to form the helical wire from a straight wire and to provide the helical wire as a consumable electrode in a welding or cladding application. The helical wire can be, for example, solid, tubular, or seamless tubular. The torch concurrently forms the helical wire and provides welding current for the welding or cladding application.

Abstract: A dissimilar material joined body is obtained by subjecting to electrical energizing under pressure and joining with electrodes a laminated member, which is of a structure in which a first plate-shaped part and a second plate-shaped part having a higher melting point than that of the first plate-shaped part are superimposed on each other. A concave portion having a shape corresponding to the outer shape of an electrode is formed on the surface of the first plate-shaped part on a side thereof opposite to the second plate-shaped part. The first plate-shaped part includes protrusions, which are inserted into through holes formed in the second plate-shaped part. A method of joining dissimilar materials includes a hole forming step, a stacking step, a pressure energizing step, and a solidification step.

Abstract: A spot welding method able to simply prevent liquid metal embrittlement cracks in spot welding of plated steel sheets, comprising, before spot welding, removing the plating at least in a zone including the inside of a circle centered at a scheduled location where the center of the nugget is formed and having an outer circumference of the inside of the outer edge of a weld affected zone or a zone at the mated surfaces of the steel sheets to be welded at the inside of a circle sharing a center of a scheduled location becoming the center of the nugget formed at the mated surfaces of the steel sheets and having an outer circumference of the inside of the outer edge of a weld affected zone

Abstract: The invention relates to ultrasonic welding tongs (10) for performing ultrasonic welding on a tubular electrically conductive welding medium (20), wherein a first welding jaw or a second welding jaw and a welding-medium stop device (21), which delimits a welding-medium holding space (19) formed between the welding jaws, are each electrically conductive and arranged electrically isolated from each other, the electrically conductive welding jaw and the electrically conductive welding-medium stop device forming components of a safety circuit in such a manner that a welding process including a closing of the welding jaws is triggered after the safety circuit has been closed by the formation of an electrical contact between the electrically conductive welding jaw and the welding-medium stop device by way of the welding medium.

Abstract: A plastic laminate has a plastic fabric formed from woven-together film strips of a plastic containing an additive that increases the absorption of laser radiation and an outer film bonded to the fabric and having at least one first film layer formed of a plastic that is free of laser-absorbing additive.

Abstract: An additive manufacturing apparatus comprises a processing chamber defining a window for receiving a laser beam and an optical module. The optical module is removably-mountable to the processing chamber for delivering the laser beam through the window. The optical module contains optical components for focusing and steering the laser beam and a controlled atmosphere can be maintained within the module.

Abstract: A method of producing a micromachined workpiece by laser micromachining includes applying a protective layer (SS) to a surface (OF) of the workpiece (WS) and machining the surface in a machining area by a laser beam (LS) through the protective layer, wherein the protective layer (SS) is produced using a coating fluid (SF) containing an at least partially volatile carrier liquid (TF) in which metallic and/or ceramic particles (PT) are dispersed; the coating fluid (SF) is applied to the surface (OF) such that at least the machining area (MA) is covered with a protective coating fluid layer (SSF); the applied coating is dried to reduce the content of carrier liquid (TF) such that a protective layer (SS) forms, which is essentially composed of the particles (PT) of the applied coating fluid or of these particles and a reduced content of the carrier liquid relative to the coating fluid; and machining of the machining areas is carried out by a laser beam (LS) irradiated through the protective layer onto the workpie

Abstract: A laser lap welding method is provided. The laser lap welding method includes linearly scanning one side surface of overlapped plural workpieces with a laser beam in a linear scanning range of from a welding start point of the one side surface to a welding end point thereof to weld the plural workpieces; controlling a power of the laser beam to gradually decrease until the laser beam reaches the welding end point when the laser beam reaches a laser power control point in the linear scanning range a predetermined time before the laser beam reaches the welding end point; and performing circular laser scanning using the laser beam around an axis extending in a depth direction of the plural workpieces through the welding end point after the laser beam reaches the welding end point to circularly melt and fluidize a portion of the plural workpieces around the welding end point.

Abstract: The laser welding method includes: a step of applying, with a laser head, a laser to a joint part of electrical conductors serving as metal members to be welded and detecting, with an infrared sensor, reflected light of the laser from the joint part or detecting, with a visible light sensor, light emitted from metal vapor; and a step of comparing the detection values of the infrared sensor and the visible light sensor and setting values respectively so as to determine whether or not energy absorption is started in the electrical conductors and adjusting the control of the application of the laser based on timing at which the energy absorption is determined to be started.

Abstract: The present disclosure relates to plants for an additive production method. The teachings thereof may be embodied in a plant with a process chamber including a device for accommodating a powder bed. For example, a plant for an additive production method may include: a process chamber accommodating a structure for a powder bed; a bottom structure and a side boundary for the powder bed; a heating device; and a thermal insulation structure surrounding the powder chamber on the side boundary. The insulation structure may include a trough-shaped recess. The structure for the powder bed may be inserted into the trough-shaped recess of the insulation structure.

Abstract: An example system may include a material source and a substrate having a molten pool on a surface of the substrate, wherein the molten pool faces a downward direction defined with respect to gravity. The system may include a computing device. An example technique may include, by the computing device, controlling the material source to direct a stream of solid material to the molten pool in an upward direction defined with respect to gravity. The material combines with the molten pool to form a deposited volume of a plurality of deposited volumes. The plurality of deposited volumes defines a component. An example computer readable storage medium may include instructions that, when executed, cause at least one processor to control, based on a digital representation of the component, an energy source to direct an energy beam at the substrate to form the molten pool, and control the material source.

Abstract: Provided is an epoch-making method in which an original sheet is continuously fed, and a rectangular electrode sheet with a tab can be cut out from the original sheet with a normal laser beam during the continuous feeding. The original sheet 1 is continuously moved. An ear portion 1b is separated from an electrode portion 1a with a first laser beam L1 in an ear portion separating region provided in the middle of movement of the original sheet 1, is taken up at a position where the ear portion 1b is separated, in a direction separated from a running direction of the electrode portion 1a, and the laser beam L1 is moved in the ear portion separating step to cut out a tab 5 connected to the electrode portion 1a, from the ear portion 1b.

Abstract: A solder material includes 25 to 45 mass % of Sn, 30 to 40 mass % of Sb, 3 to 8 mass % of Cu, 25 mass % or less of Ag, and 1.3 to 6 mass % of In.

Abstract: A clamping structure configured to be secured about at least two pipes to securely hold the pipes adjacent each other during a pipeline assembly operation is disclosed. The device can be further used to adjust the relative positions of the two pipes and maintain the relative positions while the pipes are caused to be permanently affixed to each other. Some embodiments can include a clamping structure with a plurality of hingedly engaged clamp members and at least one spatial adjustment mechanism extending therefrom, the configurations of which may provide weld-access points that are conducive to the pipeline assembly operation.

Abstract: A method for manufacturing a component of a rotary machine, the component extends in an axial direction and a radial direction vertical thereto, and has an inner channel, extending from a first end in a center of the component to a second end at a radial limiting surface of the component and which is partially closed. A blank includes the center of the component and is limited by an outer surface in the radial direction. The maximum dimension of the outer surface in the radial direction is smaller than the dimension of the limiting surface in the radial direction, A first subtractive process step is performed such that a part of the channel is manufactured by a machining process, with the part extending from the first end of the channel to the outer surface of the blank. Afterwards the channel is finished by a build-up process on the blank.

Abstract: A workpiece lifting and lowering device is provided with: a workpiece base supported as to be capable of being lifted and lowered, and mounting a workpiece; a link mechanism connected to the workpiece base, and lifting and lowering the workpiece base by converting a rotation motion to a lifting and lowering motion; and a driving mechanism rotationally driving the link mechanism through a transmission member.

Abstract: A controller of a cutting device includes a first reference point detection processor detecting an actual position of a first reference point on a top surface of a first protrusion of a magazine, a second reference point detection processor detecting an actual position of a second reference point on a top surface of the second protrusion of the magazine, a sensor offset calculation processor calculating an offset of an actual position of a tool sensor of the magazine with respect to a designed position of the tool sensor based on the first reference point and the second reference point, a stocker offset calculation processor calculating an offset of an actual position of the stocker of the magazine with respect to a designed position of the stocker based on the first reference point and the second reference point, and a movement control processor controlling a movement mechanism based on the offset of the tool sensor and the offset of the stocker.

Abstract: The invention relates to pallet changers and methods for processing sheet-like materials with at least two movably arranged pallets movably positioned in a main frame and having a support surface for receiving a sheet-like material. The pallets are moved in alternation with a drive from the main frame into a material processing machine and back to the main frame. The drive comprises a motor, which drives a drive element, which moves the pallets. A processing device is provided on the main frame to process sheet-like material positioned on the pallets in the main frame.

Abstract: An apparatus for machining a workpiece has a spindle actuable to rotate about an axis, with a flycutter wheel mounted to the spindle. At least one cutting tool is coupled to the flycutter wheel and disposed to score a workpiece during rotation of the flycutter wheel. A translation mechanism is disposed to urge the workpiece into the path of the at least one cutting tool. A compressed gas delivery system is actuable to force a flow of gas through the spindle and through one or more conduits formed within the flycutter wheel to the at least one cutting tool.

Abstract: A tool path-generating device for generating a tool path for moving a tool and a workpiece relative to each other and processing said workpiece is equipped with: an opposite path-extracting section for extracting two tool paths, the movement directions of which are roughly opposite to each other; a reversal position-calculating section for calculating a reversal position at which the tool feed direction is reversed at a position, between the endpoint of one of the two tool paths and the starting point of the other of the two tool paths, that is separated from the workpiece; and a reversal path-generating section for calculating a connecting path that passes through the endpoint of one of the two tool paths, the reversal position, and the starting point of the other of the two tool paths.

Abstract: A machine tool includes: a plurality of machining units, each including: a first saddle movable in a right-left direction; a second saddle supported by the first saddle and movable in an up-down direction; and a spindle device supported by the second saddle and movable in a front-rear direction. The plurality of machining units are arranged in the right-left direction such that spindles provided in the respective spindle devices are parallel to each other. The machining tool further includes an X-axis moving mechanism that moves the first saddle in the right-left direction; and a control device that controls an operation of the X-axis moving mechanism during machining of a workpiece and during correction of a spindle spacing between the machining units. A plurality of the X-axis moving mechanisms are provided corresponding to the respective machining units.

Abstract: The wear status of a micro-endmill tool may be inferred by monitoring the chip production rate of the tool in operation. Chips may be extracted from a work area, captured on an adhesive surface, imaged, and counted to determine the chip production rate. When the rate of chip production falls, the feed rate of the micro-endmill may be modified to a level suitable for the current state of tool wear. In this manner, costly and inconvenient work stoppages to evaluate the wear status of a tool are eliminated.

Abstract: A grinding wheel for grinding a wafer held on a holding table includes: a first circular annular plate mounted to a mount of a grinding apparatus; a tubular body extending downward from an outer circumference of the first circular annular plate; a second circular annular plate connected to a lower end of the tubular body; a plurality of grindstones arranged in an annular pattern on a lower surface of the second circular annular plate; an annular ultrasonic oscillation section disposed on an upper surface of the second circular annular plate so as to surround an opening; and an ultrasonic reception section that receives an ultrasonic vibration transmitted from the ultrasonic oscillation section to the grindstones.