WO2020231681A1 - Système et procédé d'essai de résistance de bord avec visualisation de contrainte en temps réel dans des panneaux de verre ultra-minces - Google Patents

Système et procédé d'essai de résistance de bord avec visualisation de contrainte en temps réel dans des panneaux de verre ultra-minces Download PDF

Info

Publication number
WO2020231681A1
WO2020231681A1 PCT/US2020/031551 US2020031551W WO2020231681A1 WO 2020231681 A1 WO2020231681 A1 WO 2020231681A1 US 2020031551 W US2020031551 W US 2020031551W WO 2020231681 A1 WO2020231681 A1 WO 2020231681A1
Authority
WO
WIPO (PCT)
Prior art keywords
sheet
load
measurement
region
stress
Prior art date
Application number
PCT/US2020/031551
Other languages
English (en)
Inventor
Balamurugan MEENAKSHI SUNDARAM
Douglas Miles Noni Jr.
Jamie Todd Westbrook
Original Assignee
Corning Incorporated
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 Corning Incorporated filed Critical Corning Incorporated
Priority to KR1020217041216A priority Critical patent/KR20210156325A/ko
Priority to JP2021567944A priority patent/JP2022532609A/ja
Priority to CN202080042343.8A priority patent/CN113924469A/zh
Publication of WO2020231681A1 publication Critical patent/WO2020231681A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/02—Details
    • G01N3/06—Special adaptations of indicating or recording means
    • G01N3/068—Special adaptations of indicating or recording means with optical indicating or recording means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/20—Investigating strength properties of solid materials by application of mechanical stress by applying steady bending forces
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0014—Type of force applied
    • G01N2203/0023—Bending
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0058—Kind of property studied
    • G01N2203/0069—Fatigue, creep, strain-stress relations or elastic constants
    • G01N2203/0075—Strain-stress relations or elastic constants
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02—Details not specific for a particular testing method
    • G01N2203/026—Specifications of the specimen
    • G01N2203/0262—Shape of the specimen
    • G01N2203/0278—Thin specimens
    • G01N2203/0282—Two dimensional, e.g. tapes, webs, sheets, strips, disks or membranes
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02—Details not specific for a particular testing method
    • G01N2203/06—Indicating or recording means; Sensing means
    • G01N2203/0641—Indicating or recording means; Sensing means using optical, X-ray, ultraviolet, infrared or similar detectors
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02—Details not specific for a particular testing method
    • G01N2203/06—Indicating or recording means; Sensing means
    • G01N2203/0641—Indicating or recording means; Sensing means using optical, X-ray, ultraviolet, infrared or similar detectors
    • G01N2203/0647—Image analysis
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/38—Concrete; Lime; Mortar; Gypsum; Bricks; Ceramics; Glass
    • G01N33/388—Ceramics

Definitions

  • the present disclosure relates generally to apparatuses for testing glass and/or glass ceramics and methods of testing glass and/or glass ceramics.
  • High-performance display devices such as liquid crystal displays (LCDs) and plasma displays, are commonly used in various electronics, such as cell phones, laptops, electronic tablets, televisions, and computer monitors.
  • LCDs liquid crystal displays
  • plasma displays are commonly used in various electronics, such as cell phones, laptops, electronic tablets, televisions, and computer monitors.
  • Currently marketed display devices can employ one or more high-precision glass sheets, for example, as substrates for electronic circuit components, or as color filters, to name a few applications.
  • the leading technology for making such high-quality glass substrates is the fusion draw process, developed by Coming Incorporated, and described, e.g., in U.S. Patent Nos. 3,338,696 and 3,682,609, which are incorporated herein by reference in their entireties; however, embodiments described herein are applicable to any forming process including slot draw, redraw, float, and the like.
  • a glass sheet is typically cut to size, and then resulting sharp edges of the glass sheet are beveled by grinding and/or polishing.
  • Cutting, edge machining, grinding and other processing steps can introduce flaws, such as chips or cracks, at surfaces and edges of the glass sheet. These flaws can serve as fracture sources and thereby reduce the strength of the sheets, particularly if the glass is flexed such that the flaw experiences tensile stress. Display devices experience some flexing, thus the existence of these flaws may be of concern.
  • Flexible display devices by their very nature, may produce significant stress in the display substrate(s), either during the manufacturing process or in use. Thus, flaws that might be present in the glass may experience stresses sufficiently great that the glass will crack. Since typical display manufacturing involves cutting the glass to form individual displays, and cutting is known to create multiple flaws in the glass along the cut edge, glass substrate-based flexible display devices may have a higher probability of fracture.
  • Exemplary embodiments will be described directed to methods for the continuous measurement of the breaking strength of a glass edge by putting the edge under stress, such that stresses away from the edge are significantly less than the breaking strength at their respective locations. Additionally, using exemplary embodiments both sides of an edge can be subject to substantially the same tensile stress during the measurement. Additionally, exemplary embodiments provide a continuous high speed nature which results in at least a 30x increase in processing speed, at least a 3x increase in the amount of edge tested, and orders of magnitude of sheets processed and tested. This increase in statistical sampling can thus guarantee less leakage to the customer and is amenable to online configurations.
  • an apparatus for testing a sheet of material can include a plurality of assemblies for applying a load on a region of the sheet of material; a detection mechanism for directly obtaining a no load measurement of a surface of the region and a loaded measurement of the surface of the region while the load is applied to the region; and a processor for analyzing the no load measurement and the loaded measurement to determine stress resulting from application of the load.
  • the load produces a bend in the region of the sheet of material.
  • a method of testing a sheet of material is provided.
  • the method can include providing a sheet of material; obtaining a no load measurement of a surface of a region of the sheet; applying a load to the region of the sheet; obtaining a loaded measurement of the surface of the region of the sheet; and determining stress resulting from application of the load using the no load measurement and the loaded measurement.
  • the apparatus described herein can be used for performing the method.
  • FIG. 1 illustrates an exemplary glass manufacturing system
  • FIG. 2 is a chart showing variation of load-stress at the tension side with change in adhesive location between the panel.
  • FIG. 3 is a chart showing variation of load-stress at the tension side with change in roller engagement.
  • FIG. 4 schematic showing the location of supports and application of load for an embodiment of the apparatus disclosed herein.
  • FIG. 5 shows a sheet of material prior to and during deformation (application of load), as well as the region tracking.
  • FIG. 6 is an isometric view of an embodiment of an apparatus as disclosed herein.
  • FIG. 7 is a side view of the apparatus of FIG. 6.
  • FIG. 8 is a top view of the apparatus of FIG. 6.
  • FIG. 9A is a perspective side view of an image showing one arrangement of the assemblies contacting a sheet of material as disclosed herein.
  • FIG. 9B is a top view of a sheet of material in the arrangement of FIG. 9A.
  • FIG. 10A is a sample stress field obtains at a load of 6N.
  • FIG. 10B is a chart showing the maximum stress through a test in static mode.
  • FIG. IOC shows a comparison of stress fields generated using a digital image correlation (DIC) apparatus disclosed herein compared with stress field results generated using finite element analysis (FEA).
  • FIG. 10D shows a chart with maximum stress versus displacement calculated using the digital image correlation apparatus disclosed herein and using finite element analysis.
  • FIG. 1 1A is a schematic showing the dynamic mode of an apparatus as disclosed herein.
  • FIG. 1 IB is a schematic showing a sequence of regions being imaged as a sheet of material advances through the plurality of assemblies without a load.
  • FIG. 11 C is a schematic showing a sequence of regions being imaged as a sheet of material advances through the plurality of assemblies with an applied load.
  • FIG. 12A shows a digital image correlation stress map of an 11N load with 60 steps in between, while FIG 12B shows a stress map from the same test with only one step, which confirms they are identical.
  • FIG. 13A shows a first schematic of a sample arrangement for use in calibration (top) and a top view of the sheet depicted in the schematic (bottom).
  • FIG. 13B shows a second schematic of a sample arrangement for use in calibration (top) and a top view of the skewed sheet depicted in the schematic (bottom).
  • FIG. 13C shows a third schematic of a tilted sample arrangement for use in calibration (top) and a top view of the sheet depicted in the schematic (bottom).
  • FIG. 13D shows a schematic of a fourth sample arrangement for tilted sample arrangement for use in calibration (top) and a top view of the skewed sheet depicted in the schematic (bottom).
  • FIG. 14 shows a schematic of belt rollers that can be used in embodiments disclosed herein.
  • FIG. 15 shows a schematic of ball rollers that can be used in embodiments disclosed herein.
  • FIG. 1 depicts an exemplary glass manufacturing system 100 for producing a glass ribbon 104, such as the ones the apparatuses and methods disclosed herein are designed to evaluate.
  • the glass manufacturing system 100 can include a melting vessel 1 10, a melting to fining tube 115, a fining vessel (e.g ., finer tube) 120, a fining to stir chamber connecting tube 125 (with a level probe stand pipe 127 extending therefrom), a mixing vessel (e.g., stir chamber (static or dynamic)) 130, a stir chamber to bowl connecting tube 135, a delivery vessel (e.g., bowl) 140, a downcomer 145, and a FDM 150, which can include an inlet 155, a forming body (e.g., isopipe) 160, and a pull roll assembly 165.
  • a melting vessel 1 10 can include a melting to fining tube 115, a fining vessel (e.g ., finer tube) 120, a fining to stir chamber connecting tube 125 (with
  • Glass batch materials can be introduced into the melting vessel 110, as shown by arrow 112, to form molten glass 1 14.
  • the term "batch materials" and variations thereof are used herein to denote a mixture of glass precursor components which, upon melting, react and/or combine to form a glass.
  • the glass batch materials may be prepared and/or mixed by any known method for combining glass precursor materials.
  • the glass batch materials can comprise a dry or substantially dry mixture of glass precursor particles, e.g., without any solvent or liquid.
  • the glass batch materials may be in the form of a slurry, for example, a mixture of glass precursor particles in the presence of a liquid or solvent.
  • the batch materials may comprise glass precursor materials, such as silica, alumina, and various additional oxides, such as boron, magnesium, calcium, sodium, strontium, tin, or titanium oxides.
  • the glass batch materials may be a mixture of silica and/or alumina with one or more additional oxides.
  • the glass batch materials comprise from about 45 to about 95 wt% collectively of alumina and/or silica and from about 5 to about 55 wt% collectively of at least one oxide of boron, magnesium, calcium, sodium, strontium, tin, and/or titanium.
  • the fining vessel 120 can be connected to the melting vessel 110 by the melting to fining tube 1 15.
  • the fining vessel 120 can have a high temperature processing area that receives the molten glass from the melting vessel 1 10 and which can remove bubbles from the molten glass.
  • the fining vessel 120 can be connected to the stir chamber 130 by the fining to stir chamber connecting tube 125.
  • the stir chamber 130 can be connected to the bowl 140 by the stir chamber to bowl connecting tube 135.
  • the bowl 140 can deliver the molten glass through the downcomer 145 into the FDM 150.
  • the FDM 150 can include an inlet 155, a forming body 160, and a pull roll assembly 165.
  • the inlet 155 can receive the molten glass from the downcomer 145, from which it can flow to the forming body apparatus 160, where it is formed into a glass ribbon 104.
  • the pull roll assembly 165 can deliver the drawn glass ribbon 104 for further processing by additional optional apparatuses.
  • the glass ribbon can be further processed by a traveling anvil machine (TAM), which can include a mechanical scoring device for scoring the glass ribbon.
  • TAM traveling anvil machine
  • the scored glass can then be separated into pieces of glass sheet, machined, polished, chemically strengthened, and/or otherwise surface treated, e.g., etched, using various methods and devices known in the art. While a fusion forming process has been heretofore described, the claims appended herewith should not be so limited as embodiments are applicable to any forming process including, but not limited to, slot draw, redraw, float, and the like.
  • a glass sheet can be typically cut to size, and then resulting sharp edges of the glass sheet are beveled by grinding and/or polishing during subsequent finishing processing. During these subsequent finishing, handling or other manipulating steps, an edge stress may be imparted on the glass sheet whereby the glass sheet may break potentially causing a severe disruption in the glass manufacturing or a user’s production line. For this reason, edge strength may be tested in the manufacturing plant after production.
  • a conventional method of edge strength testing is four point vertical bending (V4PTB). V4PTB tests small samples or coupons, roughly 150 mm long by 10 mm wide, which must be cut from a main glass sheet and tested individually.
  • the measurement apparatuses and methods disclosed herein provide real-time stress distributions using Direct Image Correlation (DIG) full field imaging techniques.
  • DIG Direct Image Correlation
  • Using DIG it is possible to measure strain in both in-plane orthogonal directions simultaneously as a function of time. The stresses are determined from the measured strains.
  • the direct measuring techniques disclosed herein are more accurate than older techniques and avoid the need to develop new calibration equations and models each time the glass sheet is redesigned or reconfigured. Examples of the uses of the devices described herein include, but are not limited to:
  • an apparatus 200 for testing a sheet 204 of material can include a plurality of assemblies 206 for applying a load on a region 208 of the sheet 204 of material; a detection mechanism 210 for directly obtaining a no load measurement of a surface 212 of the region 208 and a loaded measurement of the surface 212 of the region 208 while the load is applied to the region 208; and a processor 214 for analyzing the no load measurement and the loaded measurement to determine stress resulting from application of the load.
  • the load produces a deformation 216 in the region 208 of the sheet 204 of material.
  • the material 204 is a brittle material.
  • the brittle material is glass or glass ceramic.
  • the load is sufficient to deform the region 208 of the sheet 204 of material.
  • the plurality of assemblies 206a, 206b comprises a first assembly 206a comprising a single arcuate member 218 for engaging a first side of the sheet 204 and a second assembly 206b comprising two spaced-apart, arcuate members 220a, 220b for engaging a second side of the sheet 204 opposite the first side.
  • the arcuate members are described primarily as rollers, the arcuate members can be selected from a group including, but not limited to, cylindrical rollers (FIGS. 1 lA-1 l c and 13A-13D), belt rollers (FIG. 14), and bearing rollers (FIGS. 15).
  • the arcuate members 218, 220a, 220b are belt rollers 238.
  • a belt 240a, 240b, 240c can extend around a drive shaft 242a, 242b, 242c and an arcuate tensioner 244a, 244b, 244c.
  • the arcuate tensioner can be a cylindrical roller or a static, arcuate tensioner (such as a polished metal finger with an arcuate portion contacting the belt).
  • the arcuate members 218, 220a, 220b are bearing rollers 246a, 246b, 246c.
  • the bearing rollers 246a, 246b, 246c are formed from a roller ball 248a, 248b, 248c disposed and retained within a socket 250a, 250b, 250c.
  • the single arcuate member 218 is longitudinally aligned with and between the two spaced-apart, arcuate members 220a, 220b.
  • “longitudinally” refers to the direction of motion of a sheet 204 passing through the test apparatus 200 (e.g., the machine direction).
  • the detection mechanism 210 comprises a first optic system 222 positioned on the second side 226 of the sheet 204 to detect the surface between the two spaced-apart, arcuate members 220a, 220b.
  • the apparatus 200 includes a static mode where the first optic system 222 obtains both the no load measurement and the loaded measurement. In some such embodiments, in the static mode, the load applied is increased until a predetermined load is reached or until a failure of the sheet 204 is detected.
  • the first optic system includes at least two cameras in order to detect deformation of the sheet in the no load measurement and the loaded measurement.
  • the detection mechanism 210 comprises a second optic system 224a, 224b positioned of the second side 226 of the sheet to detect the surface before it is advanced between the two spaced-apart, arcuate members 220a, 220b.
  • the second side 226 of the sheet 204 is the tension side of the sheet 204.
  • the apparatus 200 includes a dynamic mode where the sheet 204 is advanced through the plurality of assemblies 206 in a longitudinal direction, and the second optic system 224 obtains the no load measurement and the first optic system 222 obtains the loaded measurement.
  • the arcuate members 218, 220a, 220b are rollers.
  • the second optic system includes at least two cameras in order to detect deformation of the sheet in the loaded measurement.
  • the plurality of assemblies 206a, 206b are adapted for advancing the sheet 204 through the plurality of assemblies 206a, 206b in a longitudinal direction, and a plurality of stress measurements are determined continuously or intermittently along an edge of the sheet 204 passing through the plurality of assemblies.
  • the stress is determined in at least two-dimensions.
  • the two-dimensional stress is displayed as a surface plot. Examples of surface plots include those shown in FIGS. 10A, 10C, 12A, and 12B.
  • the apparatus includes a display 228 adapted for displaying the stress results.
  • a patern 230 on the surface 212 of the region 208 facilitates the no load measurement and the loaded measurement.
  • the load causes the surface 212 of the region 208 of the sheet to deform.
  • the patern 230 is used to detect the surface in the no load measurement and the sheet deformation 216 in the loaded measurement.
  • the pattern 230 helps with comparisons of the no load measurement with the loaded measurement for purposes of registration.
  • the pattern 230 is printed on the surface or projected on the surface 212.
  • a method of testing a sheet of material can include providing a sheet of material; obtaining a no load measurement of a surface of a region of the sheet; applying a load to the region of the sheet; obtaining a loaded measurement of the surface of the region of the sheet; and determining stress resulting from application of the load using the no load measurement and the loaded measurement.
  • the apparatus described herein can be used for performing the method.
  • the load causes the surface of the region of the sheet to deform.
  • a first optic system obtains both the no load measurement and the loaded measurement.
  • the load applied is increased until a predetermined load is reached or until a failure of the sheet is detected.
  • a first optic system obtains the loaded measurement and a second optic system obtains the no load measurement, and the no load measurement is obtained prior to the loaded measurement.
  • a dynamic mode the sheet is advanced (e.g., longitudinally) through a testing apparatus and the no load measurement and the loaded measurement of the surface of the region are taken sequentially and then compared in the determining step.
  • the stress is determined in at least two- dimensions. The deformation can be measured in all three dimensions with strains measured in-plane in two orthogonal directions.
  • a patern on the surface of the region facilitates the no load measurement and the loaded measurement.
  • stress is determined in a time resolved domain, i.e., the history of stress evolution is obtained. This can be true in either a static mode, where a load is gradually increased until sheet failure, or dynamic mode where the sheet is advanced through the plurality of assemblies, which apply a predetermined load.
  • Suitable laminate structures can include plural glass sheets having one or more intermediate polymeric layers or can also, in alternative embodiments, include a structure having a thin film transistor glass substrate and color filter glass substrate having one or more films there between or adjacent to either or both substrates.
  • a sheet 204 or glass sheet herein, reference can also be made to glass, glass-ceramic, plastic, as well as, laminate structures and other panels.
  • the sheet 204 may have length/width dimensions ranging from about 5 mm / 5 mm, to about 100 mm / 100 mm, to about 600 mm / 600 mm, to about 1000 mm / 1000 mm, to about 2300 mm / 2600 mm, to about 4000 mm / 4000 mm and all subranges there between.
  • Glass sheets in panels or laminate structures may also have length/width dimensions ranging from about 5 mm / 5 mm, to about 100 mm / 100 mm, to about 600 mm / 600 mm, to about 2300 mm / 2600 mm, to about 4000 mm / 4000 mm and all subranges there between.
  • adjacent glass sheets in panels or laminate structures may have different length/width dimensions which can result in an overlap of one sheet on the other and on one or more sides of such sheets.
  • Exemplary glass thicknesses for single glass sheets or each glass sheet contained in a panel or laminate structure can be less than 0.1 mm (e.g., as low as 10 microns) to thicknesses greater than 5 mm, between 0.1 mm to 3 mm, between 0.4 mm to 2 mm, between 0.5 mm to 1 mm, between 0.5 mm to 0.7 mm.
  • the table 202 is adapted to support the sheet 204 of material and can be formed of any suitable material including but not limited to steel, carbon fiber, and the like.
  • the table 202 may include a plurality of driving mechanisms which are configured to move the glass sheet 204 into a predetermined position to commence a measurement cycle or to advance the sheet 204 for continuous testing.
  • a predetermined portion of an edge of the sheet 204 is used for testing.
  • a width of this predetermined portion ranges from about 1 mm to about 5 mm, from about 1.5 mm to about 3.5 mm, from about 2 mm to about 3 mm, and all subranges there between.
  • only the final 2 mm of the surface of the glass sheet is in contact with roller assemblies contained in a test apparatus 200 to ensure stress concentration is at the glass sheet edge as well as to minimize opportunity of rolling over particles which could create surface cracks.
  • the predetermined portion is measured with respect to the smaller of the glass sheets in the structure (i.e., the non- overlapping sheet).
  • the arcuate members 218, 220a, 220b in each or any of the assemblies 206 can be compliant to minimize the risk of creating a break in the sheet 204 during non-destructive testing (e.g., not evaluating maximum stress).
  • the arcuate members or rollers can be selected to have sufficient compliance while being able to provide a long life to minimize maintenance and downtime as well as sufficient friction to allow the roller to roll freely on the glass surface.
  • Exemplary arcuate member materials can include hardened steel rollers, steel rollers, urethane rollers, polyetheretherketone (PEEK) rollers, Shore 80 hardness urethane rollers, polycarbonate (PC) rollers (e.g., Lexan or the like), high-density polyethylene (HPDE) rollers, Shore 90 hardness urethane rollers, urethane coated rollers, or the like.
  • Exemplary urethane rollers can also be employed to reduce rolling noise which can contaminate any signals used by the system, feedback or otherwise.
  • urethane or urethane coated rollers can be used to accommodate debris in the roller path and to make y-direction stress profiles have no inboard stress concentrations. In embodiments used to measure edge strength of panels and laminate structures, it was discovered that rollers having less compliance (e.g., PC, HPDE, etc.) were required to achieve adequate edge strength testing results.
  • Exemplary dimensions for each arcuate member or roller can vary depending on the particular embodiment of the present subject matter.
  • roller dimensions can range from a 5 mm to a 15 mm outside diameter (OD), from a 7 mm to a 12 mm OD, from a 9 mm to a 10 mm OD.
  • an exemplary roller dimension can be about 9 mm OD so that stress can be applied nearly all the way to a comer of a glass sheet which is important as many customer issues occur in this area.
  • Exemplary systems can also traverse a glass edge at speeds ranging from 50 mm/s to 500 mm/s or more, or from 200 mm/s to 400 mm/s or more.
  • Exemplary systems do not have any limitations with regards to glass thickness and thus can be used on glass having a thicknesses less than 0.1 mm (e.g., as low as 0.01 mm) to thicknesses greater than 5 mm, between 0.1 mm to 3 mm, between 0.4 mm to 2 mm, between 0.5 mm to 1 mm, between 0.5 mm to 0.7 mm.
  • a high speed closed loop stress control mechanism can be employed to detect cracks as well as ensure applied stress is within a predetermined value of a target, e.g., 2 MPa of target.
  • a load cart be applied to a glass sheet 204 using the single arcuate member 218 whereby a load cell signal can he sent to a high speed controller (not shown) which continuously monitors for cracks.
  • This load cell signal can also be used to control the applied load while traversing the edge at a predetermined speed (e.g., 100 mm/sec to 500 mm/'sec or more).
  • Exemplary embodiments lead to a drastic reduction in the amount of time devoted to edge quality control, a dramatic increase in total glass tested versus glass produced, a dramatic increase in the percentage of edge perimeter tested, and a means for simultaneous process feedback for use in pursuit of product improvement.
  • embodiments can interrogate surface features as well.
  • some features on the surface of the glass sheet e.g., particle contamination and/or visible types of surface defects such as pits, chips or scratches, can be employed with embodiments of the present subject matter.
  • the embodiments would utilize size, shape and/or depth distributions, i.e., a dimensional metric, of such surface defects.
  • Exemplary and non-limiting surface features include surface proximity regions (e.g., approximately 20 mm inboard from the edge) and interface regions (where the surface meets the edge) and any size, shape or depth feature of surface defects.
  • Such dimensional metrics can be used alone or with strength metrics obtained from edge features.
  • the test length may span the entirety of a glass sheet edge or may be conducted on a portion(s) of a glass sheet edge.
  • the test length may span from as little as about 1 mm to 5 mm to as much as about 2600 mm, 3000 mm, 4000 mm or more depending upon the length of the glass edge.
  • grade qualities can be provided to the respective glass sheets and/or respective lots. Additional experiments were conducted to collect edge strength measurements on a wide variety of glass sheets and panels or laminate structures. Exemplary apparatus and method embodiments can be used to measure edge strengths from 100 MPa up to 200 MPa and all subranges there between. It was also discovered that for strengthened glass (e.g., chemically strengthened (ion exchanged), acid etched, or the like), edge strength measurements greater than 200 MPa (e.g., from 200 MPa to 350 MPa, from 200 MPa to 300 MPa, and all subranges there between) can be performed.
  • strengthened glass e.g., chemically strengthened (ion exchanged), acid etched, or the like
  • edge strength measurements greater than 200 MPa e.g., from 200 MPa to 350 MPa, from 200 MPa to 300 MPa, and all subranges there between
  • FIGS. 6-9B, 1 1A-11 C, and 13A-13D show schematics of an edge strength test apparatus 200 using three-point bending.
  • the vertical load is applied on the edge of thin sheet 204 with two supports 220 holding it in place.
  • the sample sheet 204 is loaded until failure and the peak load is recorded.
  • This peak load is mapped to a stress based on prior empirically developed calibration curve from strain gaging. Further, this technique provides strains/stresses along two directions (x-axis and y-axis), which is a significant improvement over the current practice of using only strains along the bending direction.
  • Digital image correlation involves point tracking. It’s a full-field optical technique to obtain displacements and thereby strains.
  • the glass sample 204 is coated with fine black and white dots 230 and stereo cameras 222a, 222b and/or 224a/224b with proper lensing are used to photograph the speckle dots 230 during the test.
  • the motion of the dot pattern 230 can be tracked.
  • This provides a displacement map which can be differentiated to obtain strains.
  • This 3D (stereo) DIC technique can be used to obtain 3D strain fields. Using the two in-plane stain fields the bending stresses can be determined using Equation (1 ):
  • E is the Elastic modulus
  • exx is the strain along the bending direction (x)
  • eyy is the strain along the other in-plane principal axis (y)
  • v is the Poisson’s ratio.
  • a conventional acrylic paint is used to form very thin (few microns) coating 230 on the glass.
  • the modulus of the paint is at least an order less than the sheet 204 and its thickness is couple of orders lower than the sheet 204, the effect of the pattern on the measurements is negligible.
  • any form of optical measurement requires a clear direct optical path to the Region of Interest (Rol) (the deformation region 208) for the measurement.
  • Rol Region of Interest
  • U.S. Patent Application Publication No. 2018-0073967 there was no direct stress measurement and its design did not allow for a clear optical path since the rollers block the path.
  • This problem is solved using the apparatus described herein, such as in FIGS. 6-9B, 1 lA-11 C, and 13A-13D. This modification and the resulting improvements is also present when the apparatus is run in a dynamic mode. Key design considerations are:
  • FIG. IOC An example of the stress field obtained at a load step of 6N along with the history of maximum stress throughout a test is shown in FIG IOC. It is believed that this kind of stress visualization/measurement was never done before. The results were correlated with numerical simulation (e.g., finite element analysis) and a good agreement is seen as shown in FIG. IOC.
  • this system apart from being a calibration unit in its static condition, can also be used in a manufacturing environment (or otherwise) with continuous edge testing in a dynamic mode.
  • the direct optical path to the surface of the material being tested facilitates the more accurate direct strain measurements relied upon herein.
  • the ability to make dynamic mode measurements is a design improvement on the existing edge measurement techniques and also adds the capability of real-time direct stress measurement.
  • the setup described above design be modified by switching the partial rollers (e.g., arcuate members) with 3 fully functional rollers that can intake the sample continuously feeding into it as shown in FIGS. 11A-11 C and 13A-13D.
  • Such a system will have the rollers in a position such that the incoming glass edge will continuously be subjected to a required bending/load.
  • the spacing between the roller and its diameter be controlled such that there is a clear optical path for camera to inspect.
  • FIG. 10D describes the methodology to accomplish real-time stress measurement in such a dynamic type of edge strength testing setup.
  • the edge strength tester needs to pre inspect the edge (without any load bending, the sample passes through the rollers) before testing so that preexisting breakages can be detected. If such a breakage is not detected then the system would malfunction or overestimate the edge strength.
  • the cameras can take series of pictures along the length of the edge as shown in FIG. 11B.
  • the cameras take another set of images at exact locations on the edge are the first series of images as shown in FIG. 1 1C by pairing corresponding images from same location and then correlating, one could obtain strain fields and thereby stresses as described previously, i.e. by correlating identically numbered images in FIG. 1 IB and 11C.
  • an apparatus with two sets of optical systems can be used to make dynamic measurements in a single pass.
  • An example of such an apparatus is shown on the left-most schematic of FIG. 11 C.
  • the system includes the first optic system 222a, 222b, the second optic system 224a, 224b, a processor 214 connected to the first and second optic systems, and a display 228 for showing the results.
  • FIGS. 12A and 12B show the results obtained from proof testing this concept and confirm that it is possible to obtain accurate results without the intermediate images.
  • the series of 150-200 images during a static test were correlated to obtain the stress distribution at 1 IN load as shown in FIG. 12A while FIG 12B shows the stress distribution obtained by correlating the 1 st image with 200 th image without intermediate steps. They are identical and the absence of intermediate steps doesn’t affect the result.
  • this embodiment describes the dynamic system of edge strength measurement for ultra-thin monolithic and laminate glass samples with real time stress visualization.
  • FIGS. 13A-13D calibration is completed prior to performing actual tests on glass panel.
  • the image correlation software gets to know the angle and distance at which camera is positioned with respect to the test sample. This will help in translating the movements of dot pattern in terms of image pixels to physical dimensions in the 3D space.
  • This calibration step is described schematically in FIGS. 13A-13D.
  • FIG. 13A shows the relative positions of the cameras (222a, 222b), rollers and the test panel. The top rollers are farther away from the panel as the test have not started yet. Now we switch the test panel with predetermined (known to image correlation software) pattern printed on a flat surface.
  • Camera takes a series of photographs of this pattern with the pattern being swiveled around in 3D space yet within camera’s focal region as depicted in FIG. 13B-13D.
  • a series of images and appropriate software can be used to develop a calibration file that will be used during the actual test on the panel to obtain strains.
  • the static mode has following design features that helps it to act as a calibration device (or benchmarking device) for studying paneFlaminate sheet design along with other parametric studies.
  • rollers can be replaced with partial roller profiles, which increases viewable area, especially near the contact points and enables studying stress distribution in that region without additional stress from rollers. It incorporates alignment techniques, such as alignment pins 236a, 236b, that align various components precisely which is very critical for the test to be accurate.
  • the method of painting the test panels with visible speckle dots renders it non- usable for consumer application.
  • non-visible speckles that can only be visible to specialized optical systems employed by the apparatus (e.g ., ultraviolet light, infrared light, or another non-visible portion of the electromagnetic spectrum).
  • the dot pattern can be random.
  • Exemplary embodiments have been described directed to a method for the continuous measurement of the breaking strength of a glass edge by putting only the edge under stress, such that stresses away from the edge are significantly less than the breaking strength at their respective locations. Additionally, using exemplary embodiments both sides of an edge can be subject to substantially the same tensile stress during the measurement.
  • One method to provide this continuous stress has been described in detail (e.g., opposed and offset rollers), but the claims appended herewith should not be so limited as it is envisioned that acoustic energy and/or infrared energy (both coherent and incoherent) can also be used for the same purpose to induce stress at the edge of a glass sheet.
  • exemplary embodiments provide a continuous high speed nature which results in at least a 30x increase in processing speed, at least a 3x increase in the amount of edge tested, and orders of magnitude of sheets processed and tested over conventional methods. This increase in statistical sampling can thus guarantee less leakage to the customer and is amenable to online configurations.
  • Embodiments and the functional operations described herein can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them.
  • Embodiments described herein can be implemented as one or more computer program products, i.e., one or more modules of computer program instructions encoded on a tangible program carrier for execution by, or to control the operation of, data processing apparatus.
  • the tangible program carrier can be a computer readable medium.
  • the computer readable medium can be a machine -readable storage device, a machine readable storage substrate, a memory device, or a combination of one or more of them.
  • processor or“controller” can encompass all apparatus, devices, and machines for processing data, including by way of embodiment a programmable processor, a computer, or multiple processors or computers.
  • the processor can include, in addition to hardware, code that creates an execution environment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them.
  • a computer program (also known as a program, software, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, or declarative or procedural languages, and it can be deployed in any form, including as a standalone program or as a module, component, subroutine, or other unit suitable for use in a computing environment.
  • a computer program does not necessarily correspond to a file in a file system.
  • a program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code).
  • a computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network.
  • the processes described herein can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output.
  • the processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit) to name a few.
  • FPGA field programmable gate array
  • ASIC application specific integrated circuit
  • processors suitable for the execution of a computer program include, by way of embodiment, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer.
  • a processor will receive instructions and data from a read only memory or a random access memory or both.
  • the essential elements of a computer are a processor for performing instructions and one or more data memory devices for storing instructions and data.
  • a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto optical disks, or optical disks.
  • mass storage devices for storing data, e.g., magnetic, magneto optical disks, or optical disks.
  • a computer need not have such devices.
  • a computer can be embedded in another device, e.g., a mobile telephone, a personal digital assistant (PDA), to name just a few.
  • PDA personal digital assistant
  • Computer readable media suitable for storing computer program instructions and data include all forms data memory including nonvolatile memory, media and memory devices, including by way of embodiment semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD-ROM disks.
  • semiconductor memory devices e.g., EPROM, EEPROM, and flash memory devices
  • magnetic disks e.g., internal hard disks or removable disks
  • magneto optical disks e.g., CD ROM and DVD-ROM disks.
  • the processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.
  • embodiments described herein can be implemented on a computer having a display device, e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, and the like for displaying information to the user and a keyboard and a pointing device, e.g., a mouse or a trackball, or a touch screen by which the user can provide input to the computer.
  • a display device e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, and the like for displaying information to the user and a keyboard and a pointing device, e.g., a mouse or a trackball, or a touch screen by which the user can provide input to the computer.
  • a keyboard and a pointing device e.g., a mouse or a trackball, or a touch screen by which the user can provide input to the computer.
  • Other kinds of devices can be used to provide for interaction with a user as well; for embodiment, input from the user can
  • Embodiments described herein can be implemented in a computing system that includes a back end component, e.g., as a data server, or that includes a middleware component, e.g., an application server, or that includes a front end component, e.g., a client computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the subject matter described herein, or any combination of one or more such back end, middleware, or front end components.
  • the components of the system can be interconnected by any form or medium of digital data communication, e.g., a communication network.
  • Embodiments of communication networks include a local area network (“LAN”) and a wide area network (“WAN”), e.g., the Internet.
  • the computing system can include clients and servers.
  • a client and server are generally remote from each other and typically interact through a communication network.
  • the relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other
  • Ranges can be expressed herein as from “about” one particular value, and/or to "about” another particular value. When such a range is expressed, examples include from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about,” it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.
  • substantially is intended to note that a described feature is equal or approximately equal to a value or description. Moreover, “substantially similar” is intended to denote that two values are equal or approximately equal. In some embodiments, “substantially similar” may denote values within about 10% of each other, such as within about 5% of each other, or within about 2% of each other.

Landscapes

  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)

Abstract

L'invention concerne un appareil d'essai d'une feuille de matériau cassant. L'appareil peut comprendre : une pluralité d'ensembles destinés à appliquer une charge sur une région de la feuille de matériau ; un mécanisme de détection destiné à obtenir directement une mesure de non-charge d'une surface de la région et une mesure de charge de la surface de la région pendant l'application de la charge sur la région ; et un processeur destiné à analyser la mesure de non-charge et la mesure de charge pour déterminer une contrainte résultant de l'application de la charge. L'appareil peut avoir recours à une imagerie optique directe de la feuille en cours d'évaluation. L'invention concerne également un procédé d'essai, à modes à la fois statiques et dynamiques, d'une feuille de matériau cassant.
PCT/US2020/031551 2019-05-15 2020-05-06 Système et procédé d'essai de résistance de bord avec visualisation de contrainte en temps réel dans des panneaux de verre ultra-minces WO2020231681A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
KR1020217041216A KR20210156325A (ko) 2019-05-15 2020-05-06 초박형 유리 패널들에서의 실시간 응력 시각화를 통한 에지 강도 테스트를 위한 시스템 및 방법
JP2021567944A JP2022532609A (ja) 2019-05-15 2020-05-06 極薄ガラスパネルでリアルタイム応力可視化を伴うエッジ強度試験を行なうためのシステムおよび方法
CN202080042343.8A CN113924469A (zh) 2019-05-15 2020-05-06 超薄玻璃面板中之实时应力可视化之边缘强度测试系统及方法

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201962848091P 2019-05-15 2019-05-15
US62/848,091 2019-05-15

Publications (1)

Publication Number Publication Date
WO2020231681A1 true WO2020231681A1 (fr) 2020-11-19

Family

ID=73289700

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2020/031551 WO2020231681A1 (fr) 2019-05-15 2020-05-06 Système et procédé d'essai de résistance de bord avec visualisation de contrainte en temps réel dans des panneaux de verre ultra-minces

Country Status (5)

Country Link
JP (1) JP2022532609A (fr)
KR (1) KR20210156325A (fr)
CN (1) CN113924469A (fr)
TW (1) TW202104865A (fr)
WO (1) WO2020231681A1 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2022533625A (ja) * 2019-05-15 2022-07-25 コーニング インコーポレイテッド 縁部強度試験方法及び装置
WO2023085706A1 (fr) 2021-11-15 2023-05-19 주식회사 엘지에너지솔루션 Module de batterie et bloc-batterie le comprenant

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4346601A (en) * 1980-08-18 1982-08-31 The Post Office Testing glass fibres
US20130215419A1 (en) * 2012-02-22 2013-08-22 Cooper S. K. Kuo Optical inspection device
KR20140122932A (ko) * 2013-04-11 2014-10-21 삼성디스플레이 주식회사 벤딩 장치 및 이를 이용한 벤딩 방법
KR20150024081A (ko) * 2013-08-26 2015-03-06 주식회사 엘지화학 유리판 결함 검출 장치 및 방법
US20180073967A1 (en) * 2015-03-13 2018-03-15 Corning Incorporated Edge strength testing methods and apparatuses

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5115142A (en) * 1989-08-18 1992-05-19 Central Glass Company, Limited Device for detecting edge of transparent sheet of laminated transparent and translucent sheet assembly
US7036364B2 (en) * 2003-09-25 2006-05-02 The Regents Of The University Of Michigan Optical system and method for measuring continuously distributed strain
US7461564B2 (en) * 2006-10-04 2008-12-09 Corning Incorporated Method and apparatus for proof testing a sheet of brittle material
GB0625260D0 (en) * 2006-12-19 2007-01-24 Renishaw Plc A method for measuring a workpiece using a machine tool
JP2011202991A (ja) * 2010-03-24 2011-10-13 Nippon Electric Glass Co Ltd 板ガラスの端部検査方法及び端部検査装置
US8511176B2 (en) * 2010-05-18 2013-08-20 Loadtest, Inc. Method and apparatus for internally determining a load applied by a jack
US8960014B2 (en) * 2012-09-21 2015-02-24 Corning Incorporated Methods of validating edge strength of a glass sheet
TWI480549B (zh) * 2012-12-21 2015-04-11 Ind Tech Res Inst 彎曲應力的測試方法及其測試裝置
GB2522233B (en) * 2014-01-17 2020-06-17 Ds Smith Packaging Ltd Board testing apparatus
US9528945B2 (en) * 2014-08-28 2016-12-27 The Boeing Company Systems and methods for detecting crack growth
DE102016116258A1 (de) * 2015-09-11 2017-03-16 Schott Ag Vorrichtung und Verfahren zur Belastungsprüfung von Scheiben eines sprödharten Materials
JP2022533625A (ja) * 2019-05-15 2022-07-25 コーニング インコーポレイテッド 縁部強度試験方法及び装置

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4346601A (en) * 1980-08-18 1982-08-31 The Post Office Testing glass fibres
US20130215419A1 (en) * 2012-02-22 2013-08-22 Cooper S. K. Kuo Optical inspection device
KR20140122932A (ko) * 2013-04-11 2014-10-21 삼성디스플레이 주식회사 벤딩 장치 및 이를 이용한 벤딩 방법
KR20150024081A (ko) * 2013-08-26 2015-03-06 주식회사 엘지화학 유리판 결함 검출 장치 및 방법
US20180073967A1 (en) * 2015-03-13 2018-03-15 Corning Incorporated Edge strength testing methods and apparatuses

Also Published As

Publication number Publication date
TW202104865A (zh) 2021-02-01
JP2022532609A (ja) 2022-07-15
KR20210156325A (ko) 2021-12-24
CN113924469A (zh) 2022-01-11

Similar Documents

Publication Publication Date Title
US11906482B2 (en) Edge strength testing of free-form glass panel
US10613007B2 (en) Edge strength testing methods and apparatuses
WO2020231683A1 (fr) Procédés et appareil de test de résistance de bord
CN109778114B (zh) 用于制造蒸镀掩模的金属板和金属板的制造方法以及蒸镀掩模和蒸镀掩模的制造方法
WO2020231681A1 (fr) Système et procédé d'essai de résistance de bord avec visualisation de contrainte en temps réel dans des panneaux de verre ultra-minces
US20080204741A1 (en) Method for quantifying defects in a transparent substrate
JP5686139B2 (ja) 液晶表示パネル用ガラス基板の製造方法
JP2015105930A (ja) 透光性基板の微小欠陥検査方法および透光性基板の微小欠陥検査装置
WO2015174114A1 (fr) Dispositif d'inspection de substrats
EP2500766A1 (fr) Procédé de fabrication continue de panneau à écran à cristaux liquides et procédé d'inspection
TW202217240A (zh) 用於檢查材料的方法和裝置
JP2010002242A (ja) ボールの目視検査用治具及び該治具を用いた目視検査方法
US20110096978A1 (en) Off-Axis Sheet-Handling Apparatus and Technique for Transmission-Mode Measurements
CN113614047B (zh) 处理粘性带的方法
CN101451960A (zh) 铬版表面膜层微小缺陷针孔的检测方法
TWM362493U (en) Testing device for display
JP2003185596A (ja) 薄型板状体の撮像処理方法および撮像処理装置
TWI443330B (zh) 用於傳送模量測之偏軸片狀物處理之裝置及技術
KR20160025159A (ko) 액정 표시 패널 평가 방법 및 이를 이용한 액정 표시 패널 평가 장치
KR20060108187A (ko) 평판 디스플레이의 검사장치
JP2006308557A (ja) 偏光フィルム検査用治具

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20806597

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2021567944

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 20217041216

Country of ref document: KR

Kind code of ref document: A

122 Ep: pct application non-entry in european phase

Ref document number: 20806597

Country of ref document: EP

Kind code of ref document: A1