1、Designation: D5824 98 (Reapproved 2011)Standard Test Method forDetermining Resistance to Delamination of Adhesive Bondsin Overlay-Wood Core Laminates Exposed to Heat andWater1This standard is issued under the fixed designation D5824; the number immediately following the designation indicates the yea
2、r oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method provides a procedure to determine theq
3、uality of bond between an overlay and a wood core in anadhesively bonded laminate. The quality of bond is determinedby measuring the resistance to delamination of the adhesivelybonded laminate when tested under specific conditions ofpreparation, conditioning, and testing. Such products include,but a
4、re not limited to, window and door components, such asstiles and rails, and other overlaid panels. Typical wood-basedcores are finger-jointed lumber, particleboard, oriented strandboard, and hardboard. Typical overlays would be veneer,high-pressure laminate, high-density polyethylene, andfiberglass-
5、reinforced plastic.1.2 Adhesive bond performance as measured by resistanceto delamination in this test method is suitable for use inadhesive product development, manufacturing quality control,and monitoring bonding processes.1.3 This test method does not provide guidance for deter-mining bond line p
6、erformance for plywood products.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.5 This standard does not purport to address all of
7、thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D907 Terminology of Adhes
8、ivesD4442 Test Methods for Direct Moisture Content Measure-ment of Wood and Wood-Base MaterialsD5266 Practice for Estimating the Percentage of WoodFailure in Adhesive Bonded JointsE6 Terminology Relating to Methods of Mechanical TestingE41 Terminology Relating To ConditioningE177 Practice for Use of
9、 the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 DefinitionsCertain terms in this test method are de-fined in Terminologies D907, E6, and E41.3.1.1 delamination, nthe separation of layer
10、s in a lami-nate because of failure of the adhesive, either in the adhesiveitself or at the interface between the adhesive and the adherend.(See Terminology D907.)3.1.2 overlay, na uniform layer of material, usually in theform of a sheet, adhesively bonded to an adherend with thepurpose of improving
11、 the appearance or physical properties ofthe laminate.3.2 Definitions of Terms Specific to This Standard:3.2.1 edge, nin an adhesively bonded laminate, the di-mension along its length and parallel to the grain where theoverlay is bonded to the core.3.2.2 end, nin an adhesively bonded laminate, the d
12、imen-sion which is perpendicular to the length of the laminate wherethe overlay is bonded to the core.4. Significance and Use4.1 This test method measures quantitatively the effects ofwater soaking and drying, and their associated swelling andshrinking stresses on adhesive bonds in overlay-laminated
13、assemblies.4.2 Adhesive bond performance is based on the ability ofthe adhesive and adhesive bonds to resist delamination duringaccelerated exposure to water and heat.4.3 Resistance to delamination when subjected to environ-mental factors is critical to the performance of the laminatedassembly in se
14、rvice.1This test method is under the jurisdiction of ASTM Committee D14 onAdhesives and is the direct responsibility of Subcommittee D14.30 on WoodAdhesivesCurrent edition approved April 1, 2011. Published April 2011. Originallyapproved in 1995. Last previous edition approved in 2003 as D5824 98 (20
15、03).DOI: 10.1520/D5824-98R11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 1
16、00 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.4 This test method is to be used to determine the quality ofadhesive bonds in overlay-wood core laminates after theadhesive has been certified by a specification appropriate forthe product, class, and end use.5. App
17、aratus5.1 Oven(s)Forced-air oven capable of maintaining 1706 5F (77 6 3C), with sufficient air circulation to ensure thatthe prescribed drying temperature is uniformly maintainedwhen the oven is fully loaded and the air flow is parallel to thefaces of the specimens. A mechanism is to be provided for
18、moisture to be removed from the chamber during drying of thespecimens.5.1.1 Use an oven to accommodate a sufficient number oftest specimens and to provide for at least 3-in. (76-mm)separation between the test specimens so that the dryingtemperature is uniformly maintained.5.2 Vacuum-Pressure VesselA
19、utoclave or similar vesselcapable of withstanding 80-psi (562-kPa) pressure, equippedwith a pump or similar device capable of drawing a vacuum of25 in. Hg (84.4 kPa). Provide a system so that pressure ismaintained at 75 psi (517 kPa).5.2.1 Use a vessel so that all the specimens are at least 2 in.(51
20、 mm) below the water level during the complete cycle.6. Test Specimens6.1 Cut laboratory specimens from prepared test panels (seeFig. 1) as described in Sections 7 and 8 to the form anddimensions shown in Fig. 2 and Table 1.6.2 Cut field specimens from test panels (see Fig. 3)totheform and dimension
21、s shown in Fig. 2 and Table 1. When thenominal width of the panel is used, the edges are to be preparedas the product would exist in service.6.3 Test ten specimens, representing at least four differentpanels.7. Preparation and Conditioning of Laboratory TestPanels7.1 Select veneer, either rotary cut
22、 or sliced, 0.063 in. (1.6mm) in thickness, and wood-based core, a minimum of 0.5 in.(13 mm) in thickness, so that they are free from defects such asknots, cracks, rough surfaces, or any unusual amount ofdiscoloration. The species and type of veneer and compositionof the wood core are to be agreed u
23、pon between the purchaserand the manufacturer of the adhesive. As an alternative toveneer, specific overlays can be used as agreed upon betweenthe purchaser and the adhesive manufacturer. Surface the coreto a thickness tolerance of 60.005 in. (0.13 mm) (see Table 1).If finger-jointed/edge-bonded cor
24、e stock is used, it must remainintact without delamination during the test cycle. Both theveneer and the wood-based core are to be 61 % of themoisture content recommended by the manufacture of theadhesive. In the absence of such a recommendation, themoisture content is to be from 10 to 12 %, based o
25、n oven-dryweight as determined on representative samples in accordancewith Method A of Test Methods D4442. Cut the veneer andwood core to a suitable size and grain orientation in order tobuild a panel with the grain of the veneer parallel to the grainof the wood core. A size that has been found to b
26、e convenientis shown in Fig. 1.7.2 Follow the adhesive manufacturers instructions forconditions and procedures for preparing the adhesive andapplying it to the wood core, as well as for assembling,pressing, and curing the panel.7.3 After assembly, condition the panels for a period ofseven days (or u
27、ntil the panels reach equilibrium) at a relativehumidity of 50 6 2 % and a temperature of 73.4 6 2F (23 61C), or condition them in accordance with a specific recom-mendation by the adhesive manufacturer.8. Preparation of Specimens8.1 Laboratory Specimens:8.1.1 Prepare the test panels as described in
28、 Section 7.8.1.2 Prepare the test panels on the sides to a uniform widthof 5 in. (127 mm). Using a sharp saw, trim 1 in. (25 mm) offboth ends of each panel by cutting perpendicular to the grain ofthe veneer. Discard the trim. Prepare each test specimen bycutting 3 in. (76 mm) in length along the gra
29、in as shown in Fig.1 and Fig. 2. Cut the panel across the grain into 3-in. (76-mm)sections to obtain a total of ten specimens from a minimum offour test panels.8.2 Field Specimens:8.2.1 Select the test panels so that they are representative ofproduction.FIG. 1 Laboratory Test PanelD5824 98 (2011)28.
30、2.2 Cut the specimens to the nominal width or a maximumof 5 in. (127 mm). Using a sharp saw, trim 1 in. (25 mm) offboth ends of each panel. Discard the trim. Cut the panel acrossthe grain into 3-in. (76-mm) sections, as shown in Fig. 3,toobtain a total of ten specimens from a minimum of four panels.
31、8.3 The number of specimens taken from each panel and thenumber of panels selected may be varied, depending on thenumber of panels selected for the test and the purpose of thetesting.8.4 Retain the specimens in the conditioning environmentdescribed in 7.3 until tested.9. Procedure9.1 Place the speci
32、mens in the pressure vessel described in5.2.1, weight down, and admit water at a temperature of 65 to80F (18 to 27C) so that all specimens are immersed at least2 in. below the water surface. Separate the test specimens withstickers, wire screens, or other means to ensure that allend-grain surfaces a
33、re freely exposed to the water. Draw andmaintain a vacuum of 25 in. Hg (84.4 kPa) for 30 min andfollow immediately with pressure application of 75 6 5 psi(517 6 35 kPa) for 30 min. Remove the specimens from thepressure vessel and place them in the oven described in 5.1.1at a temperature of 170 6 5F
34、(77 6 3C) for 4 h. Place thespecimens in the oven vertically with the faces parallel,end-grain surfaces perpendicular to the air flow, and spaced atleast 3 in. (76 mm) apart. If necessary, place the specimens onstickers to minimize contact with the oven shelves and toensure that all edges are freely
35、 exposed to the air flow.9.2 At the end of the drying period specified in 9.1, removethe specimens from the drying oven. Immediately measure andrecord the length of the overlay-wood core laminate bondlineson the ends as well as on the edges of the specimen. Measureto the nearest 0.05 in. (1.27 mm),
36、the total length of visabledelamination on the end-grain surfaces as well as on the edgesof the specimen. The use of a probe, such as a machine feelergage, has been found to be a useful aid. Do not regard failurein the wood due to checking or other causes as delamination.When the separation occurs i
37、n the wood, even though veryclose to the bond line, the separation is termed wood failure.Magnification is often necessary to determine whether thefailure is in the bond or in the wood. Ignore isolated delami-nation less than 0.1 in. (2.5 mm) long and more than 0.2 in. (5.1mm) away from the nearest
38、delamination. Determine the totallength of delamination on the end-grain dimension of thespecimens, and separately determine the total length of delami-nation on the edge-grain dimension. Use these numbers tocalculate the percent delamination as described in 10.1-10.4.10. Calculation10.1 Calculate t
39、he percent of end delamination of thespecimen by dividing the length of delamination on theend-grain surface by the total length of exposed bond line, andmultiplying by 100.10.2 Calculate the percent of edge delamination of thespecimen by dividing the length of delamination on theedge-grain surface
40、by the total length of exposed bond line, andmultiplying by 100.10.3 Calculate the percent of total delamination of thespecimen by dividing the sum of the length of delamination onthe end- and edge-grain surfaces by the total length on exposedend- and edge-bond lines, and multiplying by 100.10.4 Cal
41、culate the average end delamination, average edgedelamination, and average total delamination.11. Report11.1 Report the following for each testing condition:11.1.1 Identification of the adhesive tested, including type,manufacturer, and code numbers,11.1.2 Type and thickness of overlay, type of wood
42、coreused, and their respective moisture contents,11.1.3 Application and bonding conditions used in prepar-ing the specimens, including temperature and relative humid-ity,FIG. 2 Form and Dimensions of Test SpecimensTABLE 1 Test Specimen Dimensions, and TolerancesDimensionMeasurement,in. (mm)Tolerance
43、,in. (mm)Specimen widthA5 (127) 60.031 (0.79)Specimen length 3 (76) 60.031 (0.79)Specimen thickness, minB0.625 (15.9) 60.031 (0.79)Wood core thickness, minB0.5 (12.7) 60.031 (0.79)Overlay thickness, minB0.063 (1.6) 60.005 (0.13)AThe specimen width is nominal or cut to a maximum of 5 in.BFor field-pr
44、epared specimens, the minimum overlay thickness is 0.050 in. (1.3mm). Alternative thickness is permitted as agreed upon between the purchaserand the adhesive manufacturer.D5824 98 (2011)311.1.4 Conditioning procedure for the specimens,11.1.5 Number of panels represented,11.1.6 Number of specimens te
45、sted,11.1.7 Individual test results identified in terms of specimennumber,11.1.8 Maximum and minimum delamination for end andedge surfaces. The standard deviations of all test means forend, edge, and total delamination may be included in the reportat the option of either the purchaser or the manufac
46、turer of theadhesive.11.1.9 The mean end, edge, and total delamination.12. Precision and Bias312.1 Round-robin studies were conducted to determine theprecision of this test method and the data analyzed usingPractice E691. Factors controlled were species of veneer andwood core, adhesive, bonding cond
47、itions, and preparation oftest specimens.3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D14-1006.FIG. 3 Field Test Panel Showing Cutting Test SpecimensD5824 98 (2011)412.1.1 The round-robin studies were conducted on field-produ
48、ced panels to determine repeatability and reproducibility.The repeatability and reproducibility standard deviations werelarge for all the tests, thus indicating a low level of precision.The within-laboratory, single-operator, standard deviation (re-peatability) for determining the percent delaminati
49、on was#11.20 %. This was determined for different drying rateswhere the mean percent delamination was less than or equal to6.59 %. The between-laboratory standard deviation (reproduc-ibility) was #12.24 %. Since the reproducibility standarddeviation (between-laboratories) was not much larger than therepeatability standard deviation (within a laboratory), it mayindicate that the largest variability was due to a factor whichwould affect all laboratories.12.2 The procedure in this test method has no measure ofbias, since percent delamination is defined in terms of
