WO2016019306A2 - Article abrasif comportant des segments abrasifs en forme de z - Google Patents

Article abrasif comportant des segments abrasifs en forme de z Download PDF

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Publication number
WO2016019306A2
WO2016019306A2 PCT/US2015/043228 US2015043228W WO2016019306A2 WO 2016019306 A2 WO2016019306 A2 WO 2016019306A2 US 2015043228 W US2015043228 W US 2015043228W WO 2016019306 A2 WO2016019306 A2 WO 2016019306A2
Authority
WO
WIPO (PCT)
Prior art keywords
dampening member
mounting body
annular
segment
abrasive article
Prior art date
Application number
PCT/US2015/043228
Other languages
English (en)
Other versions
WO2016019306A3 (fr
Inventor
Ignazio Gosamo
Original Assignee
Saint-Gobain Abrasives, Inc.
Saint-Gobain Abrasifs
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Saint-Gobain Abrasives, Inc., Saint-Gobain Abrasifs filed Critical Saint-Gobain Abrasives, Inc.
Publication of WO2016019306A2 publication Critical patent/WO2016019306A2/fr
Publication of WO2016019306A3 publication Critical patent/WO2016019306A3/fr

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B41/00—Component parts such as frames, beds, carriages, headstocks
    • B24B41/007—Weight compensation; Temperature compensation; Vibration damping
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D7/00—Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting otherwise than only by their periphery, e.g. by the front face; Bushings or mountings therefor
    • B24D7/06—Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting otherwise than only by their periphery, e.g. by the front face; Bushings or mountings therefor with inserted abrasive blocks, e.g. segmental
    • B24D7/066—Grinding blocks; their mountings or supports

Definitions

  • the following is generally directed to abrasive tools and processes for forming same, and more particularly, to abrasive tools utilizing abrasive segments attached to a base and methods of assembling such tools.
  • the construction industry utilizes a variety of tools for cutting and grinding of construction materials.
  • Cutting and grinding tools are required for to remove or refinish old sections of roads.
  • quarrying and preparing finishing materials such as stone slabs used for floors and building facades, require tools for drilling, cutting, and polishing.
  • these tools include abrasive segments bonded to a base element or core, such as a plate or a wheel. As with other industries, improvements to these abrasive tools are always sought.
  • an abrasive article includes a mounting body, a dampening member coupled to the mounting body, and a Z-shaped abrasive segment coupled to the mounting body.
  • an abrasive article includes a mounting body comprising a cup- shape contour, a dampening member coupled to the mounting body, and a Z-shaped abrasive segment coupled to the housing.
  • an abrasive article in yet another aspect, includes a mounting body, a dampening member coupled to the mounting body, a sealing member disposed between the mounting body and the dampening member, and a Z-shaped abrasive segment coupled to the housing.
  • FIG. 1 includes a first plan view of an abrasive article in accordance with an embodiment.
  • FIG. 2 includes a second plan view of an abrasive article in accordance with an embodiment.
  • FIG. 3 includes a first plan view of a segment for an abrasive article in accordance with an embodiment.
  • FIG. 4 includes a second plan view of a segment for an abrasive article in accordance with an embodiment.
  • FIG. 5 includes a third plan view of a segment for an abrasive article in accordance with an embodiment.
  • FIG. 6 includes a fourth plan view of a segment for an abrasive article in accordance with an embodiment.
  • FIG. 7 includes a fifth plan view of a segment for an abrasive article in accordance with an embodiment.
  • FIG. 8 includes a sixth plan view of a segment for an abrasive article in accordance with an embodiment.
  • FIG. 9 includes a seventh plan view of a segment for an abrasive article in accordance with an embodiment.
  • FIG. 10 includes a perspective view of an abrasive article according to an embodiment.
  • FIG. 11 includes a perspective view of an abrasive article according to an embodiment.
  • FIG. 12 includes a cross-sectional view of a portion of a dampening member according to an embodiment.
  • FIG. 13 includes a perspective view of a dampening member according to an embodiment.
  • FIG. 14 includes a perspective view of a fastener engaged with a mounting body according to an embodiment.
  • the abrasive article herein can include a core and a plurality of abrasive segments affixed to the core.
  • the abrasive articles of the embodiments herein may be used to remove material from various workpieces by relative movement of the abrasive article relative to the workpiece.
  • the abrasive article can be a grinding tool for grinding metal, concrete, or natural stone.
  • the abrasive articles of embodiments herein can be a cutting tool for cutting construction materials, such as a saw for cutting concrete.
  • the abrasive articles of the embodiments herein can be used for grinding concrete or fired clay or removing asphalt.
  • the abrasive article can include multiple Z-shaped segments affixed to a core.
  • FIG. 1 and FIG. 2 illustrate an exemplary abrasive article designated 100.
  • FIG. 1 includes a front plan view of the abrasive article 100.
  • FIG. 2 includes a rear plan view of the abrasive article 100.
  • FIG. 3 through FIG. 8 include various views of a Z-shaped abrasive segment according to an embodiment.
  • FIGs. 1, 2, 10, and 11 include illustrations of an exemplary abrasive articles according to embodiments.
  • the abrasive article 100 can include a mounting body 102.
  • the mounting body 102 can include various portions, which will be described in more detail herein.
  • certain elements of the abrasive articles of the embodiments herein may be represented in certain figures and exempt from other figures, however, it will be appreciated that any of the features of the
  • the mounting body 102 can have a generally cup-shaped contour, which may appear as a cup-shaped body or bowl-shaped body.
  • the mounting body 102 can include an arbor portion 106 coupled to an intermediate portion 112 of the mounting body.
  • the arbor portion 106 can include a central opening 108 configured to engage an arbor of a grinding tool and facilitate rotary motion of the abrasive article 100 about a center 110 of the mounting body 102.
  • the center 110 of the mounting body 102 can be the center 110 of the abrasive article 100.
  • the mounting body 102 can include an intermediate portion 112 extending from the arbor portion 106.
  • the annular rim portion 116 can be coupled to the intermediate portion 112 and extend radially from the intermediate portion 112.
  • the annular rim portion 116 may define a flange on the periphery of the mounting body 102.
  • the annular rim portion 116 can include an outer peripheral surface 1001, an inner peripheral surface 1002, and an annular rim surface 1003 extending between the outer peripheral surface 1001 and the inner peripheral surface 1002.
  • the intermediate portion 112 can have a surface 114 that extends in a direction and defines a plane different than a plane defined by the annular rim surface 1003 of the annular rim portion 116.
  • the intermediate portion 112 can have a surface that is tapered relative to the annular rim portion 116.
  • the surface 114 of the intermediate portion 112 can define an arcuate surface with respect to the plane of the annular rim portion 116 and relative to a plane perpendicular to the plane defined by the annular rim portion 116.
  • the intermediate portion 112 can define a bowl-shape. Moreover, in certain instances, such as illustrated in FIGs.
  • the intermediate portion 112 can have at least one opening, and more particularly, may include a plurality of openings extending around a circumference of the intermediate portion 112.
  • the intermediate portion 112 can have a frusto- conical shape, which can extend radially outward and axially from the arbor portion 106.
  • the mounting body 102 may include an inorganic material, including for example, but not limited to a metal. More particularly, in certain instances, the mounting body can include iron, and even more particularly, can include steel.
  • At least one abrasive segment 120 and more particularly, a plurality of abrasive segments 120 can be coupled to the mounting body 102.
  • the abrasive segments 120 and the mounting body 102 may be indirectly coupled to each other, with at least one intervening component (e.g., a dampening member) disposed between the mounting body 102 and the abrasive segments 120.
  • intervening component e.g., a dampening member
  • the abrasive segments 120 can be formed separately from the mounting body 102, as described herein, and affixed to a component of the abrasive article via a brazing procedure, a welding
  • each adjacent pair of abrasive segments 120 can be separated by a gap 122.
  • FIG. 3 through FIG. 8 illustrate features of the abrasive segments 120 according to embodiments herein.
  • the abrasive segment 120 can include a body 130 that can include a generally curved inner segment portion 132 and a generally curved outer segment portion 134 spaced a radial distance, d, from the inner segment portion 132, wherein "d" is a shortest distance between the curved inner segment portion 132 and curved outer segment portion 134 along the axis 200.
  • the body 132 of the segment 130 can also include a central segment portion 136 connected to the inner segment portion 132 and the outer segment portion 134.
  • the inner segment portion 132 can include an inner circumferential wall 140 and an outer circumferential wall 142.
  • the inner segment portion 132 can also include a leading radial side wall 144 extending between the inner circumferential wall 140 and the outer
  • leading and trailing can be defined based on a direction of rotation of the abrasive article 100, which is counter-clockwise in the view illustrated in FIG. 1.
  • the inner segment portion 132 can further include a first grinding face 148 that can extend between the inner and outer circumferential walls 140, 142 and the leading and trailing radial sidewalls 144, 146. Moreover, a first serrated portion 150 can extend at least partially over the first grinding face 148.
  • the first grinding face 148 can include an area, A GF i
  • the first serrated portion 150 can include an area, A SP1 . In at least one embodiment, A SP1 can be less than A GF1 .
  • a SP1 can be not greater than about 80% A GF1 , such as not greater than about 75% A GF1 , not greater than about 70% A GF1 , not greater than about 65% A GF1 , or even not greater than about 60% A GF i.
  • a SP I can be at least about 30% A GF i, such as at least about 35% A GF i, at least about 40% A GF i, at least about 45% A GF i, or even at least about 50% A GF i.
  • a SP I can be within a range between and including any of the maximum and minimum values of A SP I described herein.
  • a SP I can be not greater than about 80% A GF i and at least about 30% A GF i, such as not greater than about 80% A GF i and at least about 35% A GF i, such as not greater than about 70% A GF i and at least about 30% A GF i. Further, A SP I can be not greater than about 60% A GF i and at least about 30% AGFI-
  • the inner segment portion 132 can have a first radial width, Wi, measured from the inner circumferential wall 140 to the outer circumferential wall 142.
  • Wi can be greater than or equal to d, which is a dimension described above.
  • Wi can be at least about 105% d, such as at least about 110% d, or even at least about 125% d.
  • Wi can be not greater than about 200% d, such as not greater than about 175% d, or not greater than about
  • Wi can also be within a range between and including any of the maximum and minimum values of Wi described herein.
  • Wi can be at least about 105% d and not greater than about 200% d, such as at least about 125% d and not greater than about 200% d, or at least about 125% d and not greater than about 150% d.
  • the outer segment portion 134 can include an inner circumferential wall 160 and an outer circumferential wall 162.
  • the outer segment portion 134 can also include a leading radial sidewall 164 extending between the inner circumferential wall 160 and the outer
  • the outer segment portion 134 can further include a second grinding face 168 that can extend between the inner and outer circumferential walls 160, 162 and the leading and trailing radial sidewalls 164, 166. Moreover, a second serrated portion 170 can extend at least partially over the second grinding face 168.
  • the second grinding face 168 can include an area, A GF2
  • the second serrated portion 170 can include an area, A SP2 . According to one embodiment, A SP2 can be less than A GF2 .
  • a SP2 can be not greater than about 80% A GF2 , such as not greater than about 75% A GF2 , not greater than about 70% A GF2 , not greater than about 65% A GF2 , or even not greater than about 60% A GF2 . Further, A SP2 can be at least about 30% A GF2 , such as at least about 35% A GF2 , at least about 40% A GF2 , at least about 45% A GF2 , or even at least about 50% A GF2 .
  • a SP2 can be within a range between and including any of the maximum and minimum values of A SP2 described herein.
  • a SP2 can be not greater than about 80% A GF2 and at least about 30% A GF2 .
  • a SP2 can be not greater than about 70% A GF2 and at least about 40% A GF2 .
  • a SP2 not greater than about 60% A GF2 and at least about 50% A GF2 .
  • the outer segment portion 134 can have a second radial width, W 2 , measured from the inner circumferential wall 160 to the outer circumferential wall 162.
  • W 2 can be equal to or greater than d, which is a dimension described above.
  • W 2 can be at least about 105% d, such as at least about 110% d, or even at least about 125% d.
  • W 2 can be not greater than about 200% d, such as not greater than about 175% d, or not greater than about 150% d.
  • W 2 can also be within a range between and including any of the maximum and minimum values of W 2 described herein.
  • W 2 can be at least about 105% d and not greater than about 200% d, such as at least about 105% d and not greater than about 175% d, or at least about 105% d and not greater than about 150% d. Further, W 2 can be at least about 110% d and not greater than about 200% d, such as at least about 110% d and not greater than about 175% d, or at least about 110% d and not greater than about 150% d. Still further, W 2 can be at least about 125% d and not greater than about 200% d,
  • INCORPORATED BY REFERENCE such as at least about 125% d and not greater than about 175% d, or at least about 125% d and not greater than about 150% d.
  • a SP1 can be not greater than about A SP2 .
  • a SP1 can be not greater than about 95% A SP2 , such as not greater than about 90% A SP2 , not greater than about 85% A SP2 , or not greater than about 80% A SP2 .
  • a SP1 at least about 50% A SP2 , such as at least about 55% A SP2 , or at least about 60% A SP2 .
  • a SP i can be within a range between and including any of the maximum and minimum values of A SP i described herein.
  • a SP i can be not greater than about 95% A SP2 and at least about 50% A SP2 , such as not greater than about 95% A SP2 and at least about 55% A SP2 , or not greater than about 95% A SP2 and at least about 60% A SP2 .
  • a SP i can be not greater than about 90% A SP2 and at least about 50% A SP2 , such as not greater than about 90% A SP2 and at least about 55% A SP2 , or not greater than about 90% A SP2 and at least about 60% A SP2 .
  • a SP i can be not greater than about 85% A SP2 and at least about 50% A SP2 , such as not greater than about 85% A SP2 and at least about 55% A SP2 , or not greater than about 85% A SP2 and at least about 60% A SP2 .
  • a SP i can be not greater than about 80% A SP2 and at least about 50% A SP2 , such as not greater than about 80% A SP2 and at least about 55% A SP2 , or not greater than about 80% A SP2 and at least about 60% A SP2 .
  • the outer segment portion 134 can further include a plurality of outer peripheral serrations 172 formed in the outer circumferential wall 162 of the outer segment portion 134.
  • the outer peripheral serrations 172 can extend along the entire outer circumferential wall 162 from the leading radial sidewall 164 to the trailing radial sidewall 166 of the outer segment portion 134.
  • the outer peripheral serrations 172 can form a sinusoidal wave structure along the outer circumferential wall 162.
  • the outer circumferential wall 162 have a circumferential length, L 0 cw > and the sinusoidal wave structure can includes a wavelength
  • WL S ws- WL S ws can be not greater than about 0.2 Locw, such as not greater than about 0.175 L 0 cw, not greater than about 0.15 L 0 cw, or not greater than about 0.125 L 0 cw-
  • WL S ws can be at least about 0.05 L 0 cw, such as at least about 0.06 Locw, at least about 0.07 L 0 cw, at least about 0.08 L 0 cw, or at least about 0.09 L 0 cw- WL S ws can be within a range between and including any of the maximum and minimum values of WL S ws described herein.
  • WL S ws can be not greater than about 0.2 L 0 cw and at least about 0.05 L 0 cw, such as not greater than about 0.2 L 0 cw and at least about 0.06 L 0 cw, not greater than about 0.2 L 0 cw and at least about 0.07 L 0 cw, not greater than about 0.2 L 0 cw and at least about 0.08 L 0 cw, or not greater than about 0.2 L 0 cw and at least about 0.09 L 0 cw-
  • WL SWS can be not greater than about 0.175 L 0 cw and at least about 0.05 L 0 cw > such as not greater than about 0.175 L 0 cw and at least about 0.06 L 0 cw > not greater than about 0.175 L 0 cw and at least about 0.07 L 0 cw > not greater than about 0.175 L 0 cw and at least about 0.08 L 0
  • WL SWS can be not greater than about 0.125 L 0 cw and at least about 0.05 L 0 cw > such as not greater than about 0.125 LQ CW and at least about 0.06 L 0 cw > not greater than about 0.125 L 0 cw and at least about 0.07 L 0 cw > not greater than about 0.125 L 0 cw and at least about 0.08 L 0 cw, or not greater than about 0.125 L 0 cw and at least about 0.09 L 0 cw-
  • the central segment portion 136 can include a leading radial sidewall 180 that can extend from the outer circumferential wall 142 of the inner segment portion 132 to the inner circumferential wall 160 of the outer segment portion 134.
  • the central segment portion 136 can also include a trailing radial sidewall 182 that can extend from the outer circumferential wall 142 of the inner segment portion 132 to the inner circumferential wall 160 of the outer segment portion 134.
  • leading radial sidewall 180 of the central segment portion 136 can establish an acute angle, a, with respect to the outer circumferential wall 142 of the inner segment portion 132 and an obtuse angle, ⁇ , with respect the inner circumferential wall 160 of the outer segment portion 136.
  • a can be not greater than about 90°, such as not greater than about 75°, not greater than about 70°, not greater than about 65°, or not greater than about 60°.
  • a can be at least about 40°, such as at least about 45°, at least about 50°, or at least about 55°.
  • a can be within a range between and including any of the values of a described herein.
  • a can be not greater than about 90° and at least about 40°, such as not greater than about 90° and at least about 45°, not greater than about 90° and at least about 50°, or not greater than about 90° and at least about 55°.
  • a can be not greater than about 75° and at least about 40°, such as not greater than about 75° and at least about 45°, not greater than about 75° and at least about 50°, or not greater than about 75° and at least about 55°. Additionally, a can be not greater than about 70° and at least about 40°, such as not greater than about 70° and at least about 45°, not greater than about 70° and at least about 50°, or not greater than about 70° and at least about 55°. In another aspect, a can be not greater than about 65° and at least about 40°, such as not greater than about 65° and at least about 45°, not greater than about 65° and at least about 50°, or not greater than about 65° and at least about 55°. Still further, a can be not greater than about 60° and at least about 40°, such as not greater than about 60° and at least about 45°, not greater than about 60° and at least about 50°, or not greater than about 60° and at least about 55°.
  • ⁇ can be greater than about 90°, such as at least about 115°, at least about 120°, at least about 125°, or at least about 130°. Moreover, ⁇ can be not greater than about 150°, such as not greater than about 145°, not greater than about 140°, or not greater than about 135°. In another aspect, ⁇ can be within a range between and including any of the maximum and minimum values of ⁇ described herein. For example, ⁇ can be greater than about 90° and not greater than about 150°, such
  • INCORPORATED BY REFERENCE as greater than about 90° and not greater than about 145°, greater than about 90° and not greater than about 140°, or greater than about 90° and not greater than about 135°.
  • ⁇ can be at least about 115° and not greater than about 150°, such as at least about 115° and not greater than about 145°, at least about 115° and not greater than about 140°, or at least about 115° and not greater than about 135°.
  • ⁇ can be at least about 120° and not greater than about 150°, such as at least about 120° and not greater than about 145°, at least about 120° and not greater than about 140°, or at least about 120° and not greater than about 135°.
  • ⁇ can be at least about 125° and not greater than about 150°, such as at least about 125° and not greater than about 145°, at least about 125° and not greater than about 140°, or at least about 125° and not greater than about 135°. Even further, ⁇ can be at least about 130° and not greater than about 150°, such as at least about 130° and not greater than about 145°, at least about 130° and not greater than about 140°, or at least about 130° and not greater than about 135°.
  • each serrated portion 150, 170 can include a plurality of serrations 190.
  • Each serration includes a leading edge 192, a trailing edge 194, and a ramped surface 196 extending there between.
  • each ramped surface 196 can extend at an angle, ⁇ , into the first grinding face 148 or the second grinding face 168 from the trailing edge 194 to the leading edge 192.
  • ⁇ can be at least about 10°, such as at least about 12.5°, or at least about 15°.
  • ⁇ can be not greater than about 30°, such as not greater than about 25°, or not greater than about 20°.
  • ⁇ can be within a range between and including any of the maximum and minimum values described herein.
  • ⁇ can be at least about 10° and not greater than about 30°, such as at least about 10° and not greater than about 25°, or at least about 10° and not greater than about 20°. Further, ⁇ can be at least about 12.5° and not greater than about 30°, such as at least about 12.5° and not greater than about 25°, or at least about 12.5° and not greater than about 20°. Still further, ⁇ can be at least about 15° and not greater than about 30°, such as at least about 15° and not greater than about 25°, or at least about 15° and not greater than about 20°.
  • the abrasive segment 120 can include a thickness, T A s, measured from a rear face to a front face, e.g., the first grinding face 148 or the second grinding face 168.
  • the trailing edge 194 of each serration 190 can extend a distance, D TE s, out from the first grinding face 148 or the second grinding face 168 and measured perpendicular to the first grinding face 148 or the second grinding face 168 and D TE s can be not greater than about 0.125 T A s, such as not greater than about 0.1 T A s, not greater than about 0.075 T A s, or not greater than about 0.05 T AS .
  • DTES can be at least about 0.0075 T AS , such as at least about 0.01 T AS , at least about 0.0125 T AS , or at least about 0.015 T AS . In another aspect, can be within a range between and including any of the maximum or minimum values of D TES described herein.
  • [0054] can be not greater than about 0.125 T AS and at least about 0.0075 T AS , such as not greater than about 0.125 T AS and at least about 0.01 T AS , not greater than about 0.125 T AS and at
  • INCORPORATED BY REFERENCE (RULE 20.6) least about 0.0125 T AS , or not greater than about 0.125 T AS and at least about 0.015 T AS . Further, can be not greater than about 0.1 T AS and at least about 0.0075 T AS , such as not greater than about 0.1 T AS and at least about 0.01 T AS , not greater than about 0.1 T AS and at least about 0.0125 T AS , or not greater than about 0.1 T AS and at least about 0.015 T AS .
  • DTES can be not greater than about 0.05 T AS and at least about 0.0075 T AS , such as not greater than about 0.075 T AS and at least about 0.01 T AS , not greater than about 0.075 T AS and at least about 0.0125 T AS , or not greater than about 0.075 T AS and at least about 0.015 T AS .
  • DTES can be not greater than about 0.05 T AS and at least about 0.0075 T AS , such as not greater than about 0.05 T AS and at least about 0.01 T AS , not greater than about 0.05 T AS and at least about 0.0125 T AS , or not greater than about 0.05 T AS and at least about 0.015 T AS .
  • each serration 190 can extend a distance, DLE S , into the first grinding face 148 or the second grinding face 168 and measured perpendicular to the first grinding face 148 or the second grinding face 168, and D LE s can be not greater than about 0.125 T AS , such as not greater than about 0.1 T AS , not greater than about 0.075 T AS , or not greater than about 0.05 T AS .
  • D LES can be at least about 0.0075 T AS , such as at least about 0.01 T AS , at least about 0.0125 T AS , or at least about 0.015 T AS .
  • D LES can be within a range between and including any of the maximum or minimum values of D LES described herein.
  • D LES can be not greater than about 0.125 T AS and at least about 0.0075 T AS , such as not greater than about 0.125 T AS and at least about 0.01 T AS , not greater than about 0.125 T AS and at least about 0.0125 T AS , or not greater than about 0.125 T AS and at least about 0.015 T AS .
  • D LES can be not greater than about 0.05 T AS and at least about 0.0075 T AS , such as not greater than about 0.075 T AS and at least about 0.01 T AS , not greater than about 0.075 T AS and at least about 0.0125 T AS , or not greater than about 0.075 T AS and at least about 0.015 T AS .
  • D LES can be not greater than about 0.05 T AS and at least about 0.0075 T AS , such as not greater than about 0.05 T AS and at least about 0.01 T AS , not greater than about 0.05 T AS and at least about 0.0125 T AS , or not greater than about 0.05 T AS and at least about 0.015 T AS .
  • the abrasive segment 120 can include a central axis 200 that can extend through a center 202 of curvature of the abrasive segment and bisect the leading radial sidewall 180 of the central segment portion 136 of the abrasive segment 120.
  • the first serrated portion 150 on the first segment portion 132 can lie entirely behind the central axis 200 with respect to a direction of rotation of the abrasive segment 120.
  • the second serrated portion 170 on the second segment portion 134 can lie entirely ahead of the central axis 200 with respect to a direction of rotation of the abrasive segment 120.
  • a portion of the inner segment portion 132 can extend ahead of the leading radial sidewall 180 of the central segment portion 136 with respect to the direction of rotation.
  • a portion of the outer segment portion 134 can extend behind the trailing radial sidewall 182 of the central segment portion 136 with respect to the direction of rotation.
  • the mounting body 102 of the abrasive article 100 described herein can be in the form of a cup, a ring, a ring section, a plate, or a disc depending upon the intended application of the abrasive article.
  • the mounting body 102 can be made of a metal or metal alloy.
  • the mounting body 102 can be made of steel, and particularly, a heat treatable steel alloys, such as 25CrMo4, 75Crl, C60, or similar steel alloys for a core having a thin cross section or simple construction steel like St 60 or similar for a thick core.
  • the mounting body 102 can have a tensile strength of at least about 600 N/mm 2 .
  • the mounting body 102 can be formed by a variety of metallurgical techniques known in the art.
  • the abrasive segments 120 can include abrasive particles embedded in a bond matrix.
  • the bond matrix can include a metal matrix having a network of interconnected pores.
  • the abrasive particles can include an abrasive material having a Mohs hardness of at least about 7.
  • the abrasive particles can include a superabrasive material, such as diamond or cubic boron nitride.
  • the abrasive particles can have a particle size of not less than about 400 US mesh, such as not less than about 100 US mesh, such as between about 25 and 80 US mesh. Depending on the application, the size can be between about 30 and 60 US mesh.
  • the abrasive particles can be present in an amount between about 2 vol to about 50 vol . Additionally, the amount of abrasive particles may depend on the application. For example, an abrasive segment for a grinding or polishing tool can include between about 3.75 and about 50 vol abrasive particles of the total volume of the abrasive segment. Alternatively, an abrasive segment for a cutting-off tool can include between about 2 vol and about 6.25 vol abrasive particles of the total volume of the abrasive segment. Further, an abrasive segment for core drilling can include between about 6.25 vol and about 20 vol abrasive particles of the total volume of the abrasive segment.
  • the metal matrix can include a metal element or metal alloy including a plurality of metal elements.
  • the metal matrix can include metal elements such as iron, tungsten, cobalt, nickel, chromium, titanium, silver, and a combination thereof.
  • the metal matrix can include a rare earth element such as cerium, lanthanum, neodymium, and a combination thereof.
  • the metal matrix can include a wear resistant component.
  • the metal matrix can include tungsten carbide, and more particularly, may consist essentially of tungsten carbide.
  • the metal matrix can include particles of individual components or pre- alloyed particles.
  • the particles can be between about 1.0 microns and about 250 microns.
  • the abrasive segments 120 can be formed such that an infiltrant is present within the interconnected network of pores within the body of the abrasive segment 120.
  • the infiltrant can partially fill, substantially fill, or even completely fill the volume of the pores extending through the volume of the abrasive segment 120.
  • the infiltrant can be a metal or metal alloy material.
  • some suitable metal elements can include copper, tin, zinc, and a combination thereof.
  • the infiltrant can be only copper.
  • the infiltrant can be a bronzing material made of a metal alloy, and particular a copper-tin metal alloy, such that it is particularly suited for welding according to embodiments herein.
  • the bronzing material can consist essentially of copper and tin.
  • Certain bronzing materials can incorporate particular contents of tin greater than about 5% by weight, such as greater than about 6% by weight, greater than about 7% by weight, or even greater than about 8% by weight. Further, certain bronzing materials can incorporate particular contents of tin less than about 20% by weight, such as less than about 15% by weight, less than about 12% by weight, or even less than about 10% by weight of the total amount of materials within the composition.
  • the bronzing material can include an amount of tin within a range between and including about 5% by weight and about 20% by weight, such as between and including about 5% by weight and about 15% by weight, between and including about 5% by weight and about 12% by weight, or between and including about 5% by weight and about 10% by weight.
  • the bronzing material can include an amount of tin within a range between and including about 6% by weight and about 20% by weight, such as between and including about 6% by weight and about 15% by weight, between and including about 6% by weight and about 12% by weight, or between and including about 6% by weight and about 10% by weight.
  • the bronzing material can include an amount of tin within a range between and including about 7% by weight and about 20% by weight, such as between and including about 7% by weight and about 15% by weight, between and including about 7% by weight and about 12% by weight, or between and including about 7% by weight and about 10% by weight.
  • the bronzing material can include an amount of tin within a range between and including about 8% by weight and about 20% by weight, such as between and including about 8% by weight and about 15% by weight, between and including about 8% by weight and about 12% by weight, or between and including about 8% by weight and about 10% by weight.
  • certain bronzing materials can be used as infiltrant material, and can have an amount of copper of at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 85%, or even at least about 88% by weight of the total amount of materials within the
  • Some bronzing materials can utilize an amount of copper within a range between about 50% and about 95%, such as between about 85% and about 95%, or even between about 88% and about 93% by weight of the total amount of materials within the composition.
  • the copper amount also can be in a range between any of these minimum and maximum values.
  • the bronzing material may contain a particularly low content of other elements, such as zinc to facilitate proper formation of the abrasive article according to the forming methods of the embodiments herein.
  • the bronzing material may utilize not greater than about 10%, such as not greater than about 5%, or even not greater than about 2% zinc. In fact, certain bronzing materials can be essentially free of zinc.
  • the abrasive segment 120 may be manufactured, such that abrasive particles can be combined with a metal matrix to form a mixture.
  • the metal matrix can include a blend of particles of the components of the metal matrix or can be pre-alloyed particles of the metal matrix.
  • the metal matrix can conform to the formula (WC) w W x Fe y Cr z X ( i_ w _ x _ y _ z) , wherein not greater than about not greater than about 0.8, not greater than about not greater than about 0.7, not greater than about not greater than about 0.8, not greater than about not greater than about 0.05, w+x+y+z not greater than about 1, and X can include other metals such as cobalt and nickel.
  • the metal matrix can conform to the formula (WC) w W x Fe y Cr z Ag v X (1 _ v _ w _ x _ y _ z) , wherein not greater than about not greater than about 0.5, not greater than about not greater than about 0.4, not greater than about not greater than about 1.0, not greater than about not greater than about 0.05, not greater than about not greater than about 0.1 , v+w+x+y+z not greater than about 1 , and X can include other metals such as cobalt and nickel.
  • the mixture of metal matrix and abrasive particles can be formed into an abrasive preform by a pressing operation, particularly a cold pressing operation, to form a porous abrasive segment.
  • the cold pressing can be carried out at a pressure within a range between and including about 50 kN/cm 2 (500 MPa) to about 250 kN/cm 2 (2500 MPa).
  • the resulting porous abrasive segment can have a network of interconnected pores.
  • the porous abrasive segment can have a porosity between about 25 vol% and 50 vol%.
  • the resulting porous abrasive segment 120 can then be subject to an infiltration process, wherein the infiltrant material is disposed within the body of the abrasive segment, and particularly, disposed within the interconnected network of pores within the body of the abrasive segment.
  • the infiltrant may be drawn into the pores of the cold pressed abrasive segment via capillary action.
  • the resulting densified abrasive segment can be not less than about 96% dense.
  • the amount of infiltrant that infiltrates the abrasive segment can be between about 20 wt% and 45 wt% of the densified abrasive segment.
  • the abrasive segment 120 can include a backing region, disposed between the abrasive segment and the base, i.e., the mounting body 102, which facilitates the joining of the abrasive segment and the mounting body 102.
  • the backing region can be a
  • the backing region can be initially formed as part of the abrasive segment 120, and particularly may be a distinct region of the abrasive segment 120 along a bottom surface of the abrasive segment 120 that has particular characteristics facilitating the joining of the abrasive segment 120 and the mounting body 102.
  • the backing region can have a lesser percentage (vol ) of abrasive particles as compared to the amount of abrasive particles within the abrasive segment 120.
  • the backing region can be essentially free of abrasive particles. This may be particularly suitable for forming methods utilizing a beam of energy (e.g., a laser) used to weld the abrasive segment 120 to the mounting body 102.
  • At least a portion of the backing region can include a bonding composition.
  • the bonding composition can include a metal or metal alloy.
  • suitable metal materials can include transition metal elements, including for example, titanium, silver, manganese, phosphorus, aluminum, magnesium, chromium, iron, lead, copper, tin, and a combination thereof.
  • the bonding composition can be similar to the infiltrant, such that the bonding composition and the infiltrant are different from each other by not greater than a single elemental species.
  • the bonding composition can be the same as the infiltrant.
  • the bonding composition can be related to the infiltrant composition in having a certain degree of commonality of elemental species. Quantitatively, an elemental weight percent difference between the bonding composition and the infiltrant composition does not exceed 20 weight percent. Elemental weight percent difference is defined as the absolute value of the difference in weight content of each element contained in the bonding composition relative to the infiltrant composition.
  • the elemental weight percent difference between the bonding composition and the infiltrant composition may, for example, not exceed 15 weight percent, 10 weight percent, 5 weight percent, or may not exceed 2 weight percent.
  • An elemental weight percent difference of about zero represents the same composition making up the backing region and the infiltrant.
  • the foregoing elemental values may be measured by any suitable analytical means, including microprobe elemental analysis, and ignores alloying that might take place along areas in which the infiltrant contacts the metal matrix.
  • the backing region can include at least about 90 wt infiltrant, such as at least about 95 wt infiltrant, such as at least about 98 wt infiltrant.
  • the infiltrant can be continuous throughout the backing region and the densified abrasive segment.
  • the backing region can be formed primarily of the infiltrant material, and in more particular instances, can consist essentially of the infiltrant material.
  • the backing region can be an infiltrated region, like the abrasive segment.
  • the backing region can include a network of interconnected pores formed between a matrix metal, and wherein the infiltrant material substantially fills the interconnected pores.
  • the backing region can contain similar amounts of matrix metal and infiltrant.
  • the backing region may be essentially free of abrasive particles.
  • the infiltrant material can act as a bronzing material in forming a joint (e.g., a welded joint) between the base and the abrasive segment.
  • the backing region can be formed of the bronzing material described herein.
  • certain backing regions can consist essentially of a copper-tin bronzing material having about 88% copper and 12% tin or 90% copper and 10% tin.
  • a method of making the abrasive article 100 can include stamping, cutting, molding, infiltrating, and a combination thereof.
  • the method can include affixing the abrasive segments 120 to the mounting body 102.
  • Affixing the abrasive segments 120 to the mounting body 102 (or other intermediate component) can include welding the abrasive segments 120 to the mounting body 102.
  • the welding process can include impinging a beam of energy at the base of each abrasive segment 120. More particularly, in the instance of a abrasive segment 120 having a backing region, welding can include impinging a beam of energy at the backing region between the abrasive segment 120 and the mounting body 102.
  • the beam of energy can be a laser, such that each abrasive segment 120 is attached to the mounting body 102 via a laser welded bond joint.
  • the laser may be a Roffin laser source commonly available from Dr. Fritsch, GmbH. It will be appreciated that all description of methods of bonding the abrasive segment to the mounting body will be the same for bonding or coupling of the abrasive segments to any intervening components described herein, including for example, a dampening member.
  • each abrasive segment 120 can be formed by pressing a green segment in a mold and curing the green segment.
  • the pressing can include hot pressing or cold pressing.
  • forming each abrasive segment 120 can include sintering a green segment, e.g., using an electro-discharge sintering process.
  • forming each abrasive segment 120 can include the infiltration method described herein.
  • each abrasive segment 120 can be include a single layer metal bond ("SLMB") segment having a core and a single layer of abrasive electro-plated, or otherwise deposited, on a cutting, or grinding surface of the core.
  • SLMB single layer metal bond
  • dampening member is configured to be in direct contact with a portion of the mounting body, wherein at least a portion of the dampening member is configured to be in direct contact with an annular rim portion of the mounting body.
  • the abrasive article may include a dampening member that can be coupled to the mounting body 102 and the abrasive segment 120.
  • the dampening member 1030 can have a generally an annular shape, which can be defined by a first major surface 1033, a second major surface 1034 spaced apart from the first major surface 1033, and interior annular surface 1032 extending between the first major surface 1033 and the second major surface 1034.
  • the interior annular surface 1032 can define a
  • the dampening member 1030 may further including an outer peripheral surface 1031 separating the first major surface 1033 and the second major surface 1034.
  • the dampening member 1030 can include a material different than a material of the mounting body 102, and more particularly, may include a material having a hardness less than a hardness of the mounting body 102.
  • the dampening member 1030 may facilitate absorbing vibrations and shocks during use (such as grinding), which can facilitate improved use conditions for a user and improved results on the workpiece.
  • the dampening member 1030 can include a material selected from the group consisting of inorganic materials, organic materials, natural materials, synthetic materials, and a combination thereof.
  • the dampening member 1030 may include a material selected from the group consisting of a metal, a metal alloy, a polymer, a resin, an elastomer, a thermoplastic, a thermoset, an adhesive, and a combination thereof.
  • the dampening member 1030 can include copper, and may consist essentially of copper.
  • the dampening member 1030 include rubber, and can consist essentially of rubber.
  • the dampening member 1030 can be an adhesive material, which may be in the form of a layer (continuous or interrupted), which can be disposed between at least one Z-shaped abrasive segment 120 and the mounting body 102.
  • the dampening member 1030 can be permanently adhered to the mounting body 102.
  • the dampening member 1030 can have an elastic modulus less than an elastic modulus of the mounting body 102.
  • the dampening member 1030 can have an elastic modulus of less than about 200 GPa, such as less than about 180 GPa, less than about 150 GPa, less than about 120 GPa, less than about 100 GPa, less than about 80 GPa, less than about 50 GPa, less than about 30 GPa, or even less than about 10 GPa.
  • 1030 can have an elastic modulus of at least about 0.01 MPa.
  • the dampening member 1030 can have a particular shape to facilitate use.
  • the dampening member 1030 can have an aspect ratio (D/t) of at least about 1.5, wherein D is a diameter of the body of the dampening member 1030 measured as a greatest distance between points on an outer peripheral surface 1031 and extending through a center point.
  • the "t” can represent the thickness of the body of the dampening member 1030 measured as a distance between the first major surface 1033 and the second major surface 1034, and more particularly, can be the smallest distance between the first major surface 1033 and second major surface 1034 at the outer peripheral surface
  • the aspect ratio (D/t) of the dampening member can be at least about 2, such as at least about 3, or even at least about 4.
  • the dampening member 1030 can have a recess 1035.
  • the recess 1035 can be in a portion of the first major surface 1033 of the dampening member 1030.
  • the dampening member 1030 can have a recess 1035 in the first major surface
  • INCORPORATED BY REFERENCE (RULE 20.6) 1033 which is configured to engage and center the mounting body 102 relative to the dampening member. More particularly, the annular rim portion 116 of the mounting body 102 can be configured to engage a portion of the recess 1035.
  • the dampening member 1030 may also include a lip 1036 extending axially from an outer peripheral surface 1031 of the dampening member 1030 and defining at least a portion of the recess 1035 at the first major surface 1033 of the dampening member 1030.
  • the lip 1036 can have an inner axial lip surface 1037, such that at least a portion of the mounting body 102 is configured to engage a portion of the inner axial lip surface 1037 when the abrasive article is assembled. More particularly, a portion of an outer peripheral surface 1031 of an annular rim portion 116 of the mounting body 102 can be configured to engage a portion of the inner axial lip surface 1037.
  • the recess 1035 can have a depth (d r ) of at least about 0.03(t dm ), wherein represents a thickness of the dampening member 1030 defined as a distance along an interior annular surface 1032 extending between the first major surface 1033 and the second major surface 1034.
  • the depth of the recess 1035 can be at least about 0.05(t dm ), at least about 0.080 ⁇ , at least about 0.10 ⁇ ), at least about 0.150 ⁇ ), or even at least about Yet, in another embodiment, the recess 1035 can have a depth of not greater than about It will be appreciated that the depth of the recess 1035 can be within a range between any of the maximum and minimum values noted above.
  • the dampening member 1030 can have an annular channel 1040 extending through at least a potion a second major surface 1034 of the dampening member 1030.
  • the annular channel 1040 can have an interior annular surface 1041, an outer annular surface 1042, and a bottom surface 1043 extending between the interior annular surface 1041 and the outer annular surface 1042.
  • the annular channel 1040 can extend axially into a portion of the body of the dampening member 1030 from the second major surface 1034.
  • the annular channel 1040 can have a depth (d ac ) defined by a length of the interior annular surface 1041 or the outer annular surface 1042, and more particularly, a distance between the bottom surface 1043 and the second major surface 1034.
  • the depth (d ac ) of the annular channel 1040 can be less than a thickness (tdm) of the dampening member 1030.
  • the annular channel 1040 can have an average width (Wac) less than an average width (Wd m ) of the dampening member 1030.
  • the average width (Wac) of the annular channel 1040 can be a distance between the interior annular surface 1041 and the outer annular surface 1042, and the average width (Wdm)of the dampening member 1030 can be a distance between the interior annular surface 1032 and the outer peripheral surface 1031.
  • the second major surface 1034 of the dampening member 1030 can have an inner annular portion 1045 and an outer annular portion 1046 separated by the annular channel 1040.
  • At least a portion of the inner annular portion 1045 can be configured to engage at least a portion of the curved inner segment portion 132 of one or more Z-shaped abrasive segments
  • at least a portion of the outer annular portion 1046 can be configured to engage at least a portion of the curved outer segment portion 136 of one or more Z-shaped abrasive segments 120.
  • the central segment portion 136 of the Z-shaped abrasive segment 120 can span and be spaced apart from the annular channel 1040 in the second major surface 1034 of the dampening member 1030.
  • the width (w iap ) of the inner annular portion 1045 can be different than a width (Woap) of the outer annular portion 1046.
  • the width of the inner annular portion 1045 can be a measure of a radial distance between an interior annular surface 1032 of the dampening member 1030 and the interior annular surface 1041 of the annular channel 1040.
  • the width (w oap ) of the outer annular portion 1046 can be a measure of a radial distance between the outer annular surface 1042 of the annular channel 1040 and an outer peripheral surface 1031 of the dampening member 1030.
  • the dampening member 1030 can also include at least one (e.g., a first ) borehole 1050, which can be configured to engage a portion of a fastener 1060.
  • the borehole 1050 can extend through the entire thickness of the dampening member 1030 from a first major surface 1033 to a second major surface 1034.
  • the borehole 1050 can have a first opening having a first diameter 1051 at the first major surface 1033 and a second opening 1052 having a second diameter different than the first diameter at the second major surface 1034 of the dampening member 1030.
  • the use of a borehole 1050 with different diameters at the first major surface 1033 and second major surface 1034 may facilitate securing the mounting body 102 and dampening member 1030 to each other using particular fasteners described herein.
  • the dampening member 1030 can have a plurality of boreholes, and more particularly, the plurality of boreholes can be substantially, evenly distributed with respect to each other throughout a circumferential distance around the dampening member.
  • the abrasive article such as the article illustrated in FIGs. 10-11 may further include a fastener 1060.
  • FIG. 14 includes a perspective view illustration of fastener 1060 engaged with a portion of the mounting body 102 according to an embodiment.
  • the fastener 1060 can be configured to couple the mounting body 102 and the dampening member 1030 to each other. More particularly, in certain instances, the fastener 1060 can be configured to engage a fastener opening 1068 in the mounting body 102.
  • the fastener 1060 can have a head 1061 and a stud 1062 extending from the head 1061. In one embodiment, the stud 1062 can have a substantially smooth surface, such that it may be unthreaded.
  • the stud 1062 can have at least one groove 1063 proximate to a distal end 1064 of the stud 1062.
  • the groove 1063 can extend circumferentially around the stud 1062.
  • the groove 1063 can be configured to engage a clamping member 1080 after extending through the mounting body 102 and the dampening member 1030 to contain the fastener 1060 in the borehole 1050 and removably couple the dampening member 1030 to the mounting body 102.
  • the stud 1062 can be configured to extend axially through a thickness of an annular rim portion
  • the abrasive article can include a plurality of fasteners, wherein each fastener 1060 of the plurality of fasteners is configured to engage and couple the mounting body 102 and the dampening member 1030.
  • the abrasive articles of the embodiments herein can further include at least one sealing member 1070, which can be configured to engage at least one fastener 1060.
  • the fastener 1060 can extend between the mounting body 102 and the dampening member 1030, and the sealing member 1070 can be configured to engage a surface of the dampening member 1030.
  • the sealing member 1070 can further engage at least a portion of the annular rim portion 116 of the mounting body 102.
  • the sealing member 1070 can be configured to engage a first major surface 1033 of the dampening member 1030.
  • the sealing member 1070 may also be configured to engage a recess 1035 of the dampening member 1030.
  • the sealing member 1070 may be an annular member configured to engage and wrap around a portion of a stud 1062 of a fastener 1060.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Polishing Bodies And Polishing Tools (AREA)

Abstract

Article abrasif comprenant un corps de montage, un élément amortisseur couplé au corps de montage, et des segments abrasifs en forme de Z ou d'une autre forme, couplés au corps de montage.
PCT/US2015/043228 2014-08-01 2015-07-31 Article abrasif comportant des segments abrasifs en forme de z WO2016019306A2 (fr)

Applications Claiming Priority (2)

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US201462032053P 2014-08-01 2014-08-01
US62/032,053 2014-08-01

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WO2016019306A3 WO2016019306A3 (fr) 2016-05-12

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3634691A4 (fr) * 2017-06-09 2021-03-31 Saint-Gobain Abrasives, Inc. Anneau de meulage à segments abrasifs concaves
WO2022090898A1 (fr) * 2020-10-28 2022-05-05 3M Innovative Properties Company Ensemble moyeu réutilisable pour articles abrasifs

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2324616A1 (de) * 1972-05-17 1973-12-06 S P A M Schleifwerkzeuge
DE10161931A1 (de) * 2001-12-17 2003-06-18 Hilti Ag Schleifscheibe mit Schleifsegmenten
JP2013512793A (ja) * 2009-12-11 2013-04-18 サンーゴバン アブレイシブズ，インコーポレイティド 研削ホイールと共に使用するための研磨物品
US9149913B2 (en) * 2012-12-31 2015-10-06 Saint-Gobain Abrasives, Inc. Abrasive article having shaped segments
US9227342B2 (en) * 2012-12-31 2016-01-05 Saint-Gobain Abrasives, Inc Abrasive article having abrasive segments with shaped gullet walls

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3634691A4 (fr) * 2017-06-09 2021-03-31 Saint-Gobain Abrasives, Inc. Anneau de meulage à segments abrasifs concaves
WO2022090898A1 (fr) * 2020-10-28 2022-05-05 3M Innovative Properties Company Ensemble moyeu réutilisable pour articles abrasifs

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