1、SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefro
2、m, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions.QUESTIONS REGARDING THIS DOCUMENT: (724) 772-8512 FAX: (724) 776-0243TO PLACE A DOCUMENT
3、 ORDER; (724) 776-4970 FAX: (724) 776-0790SAE WEB ADDRESS http:/www.sae.orgCopyright 1988 Society of Automotive Engineers, Inc.All rights reserved. Printed in U.S.A.SURFACEVEHICLE400 Commonwealth Drive, Warrendale, PA 15096-0001RECOMMENDEDPRACTICESubmitted for recognition as an American National Sta
4、ndardJ1836ISSUEDOCT88Issued 1988-10OVERLAP SHEAR TEST FOR SEALANT ADHESIVE BONDING OF AUTOMOTIVE GLASS ENCAPSULATING MATERIAL TO BODY OPENINGForewordThis Document has not changed other than to put it into the new SAE Technical Standards BoardFormat.1. ScopeThis recommended practice defines a procedu
5、re for the construction of a lap shear specimen for thepurpose of testing the bondability of an automotive sealant adhesive to the elastomeric material used inautomotive encapsulating.The present practice of encapsulating automotive glass is described as molding elastomeric material onto theouter ed
6、ge of the glass using thermoplastic or thermosetting material that quickly sets in the mold. The glassis removed from the mold with cured elastomeric material bonded to the perimeter of thee glass. Thisencapsulated glass module can now be bonded with a sealant adhesive into the body opening of a veh
7、icle.2. References2.1 Applicable PublicationThe following publication forms a part of the specification to the extent specifiedherein. Unless otherwise indicated the lastest revision of SAE publications shall apply.2.1.1 ASTM PUBLICATIONAvailable from ASTM, 100 Barr Harbor Drive, West Conshohocken,
8、PA 19428-2959.ASTMD1002Test Method for Strength Properties of Adhesives in Shear by Tension Loading (Metal-to-Metal)3. Test Substrates3.1 SubstratesThe substrates used for the construction of the lap shear specimen should be coupons madefrom automotive sheet metal or any other rigid substrate such a
9、s plastic composites used in automotive. Theother coupon should be made from elastomeric material used in automotive glass encapsulation.3.2 DimensionsThe metal test substrate and metal support substrate shall be cut into coupons 25.4 x102.0mm (1.0 x 4.0 in) at a nominal thickness of 0.8 mm (0.032 i
10、n). The elastomeric material shall be cutfrom molded sheets into 25.4 x 102.0 mm (1.0 x 4.0 in) coupons at a nominal thickness of 3.2 mm (0.125 in).All test coupons shall be free of flaws such as nicks and splinters that could give erroneous test results.3.3 Surface CoatingsThe coating used for pain
11、ting the metal or any other rigid substrate shall be recom-mended by automotive engineers.SAE J1836 Issued OCT88-2-3.4 Surface PreparationSurface preparation with respect to cleaning and primer application should be inaccordance with sealant adhesive suppliers, or automotive engineers recommendation
12、.4. Preparation of Test Joints4.1 The final joint geometry is as shown in Figure 1 with tolerance specified under 4.3.The lap shear specimen should be constructed without the metal backing as illustrated in Figure 2. The metalsupport should be bonded onto the back of the elastomeric coupon just prio
13、r to testing. The adhesive shouldbe of suitable type to have good bondability to the metal and elastomeric coupon in order to minimizestretching or premature ripping of the elastomeric coupon while testing.FIGURE 1THREE DIMENSIONAL VIEW OF OVERLAPSHEAR TEST SPECIMENFIGURE 2SIDE VIEW OF OVERLAPSHEAR
14、SPECIMENThe lap shear board should be constructed as in Figure 2, to give the proper dimensions for the lap shear asdescribed in Figure 1. The elastomeric coupons should be taped onto the board so that the one in side isapproximately 3.0 to 6.0 mm (0.12 to 0.24 in) from the edge of the board. Coupon
15、s can be laid side-by-side onthe board to make multiple lap shear specimens.4.2 Replacement of Metal with Other SubstratesThe rigid substrates that are used to replace the metalcoupons on the top section of the board in Figure 2 should be of a thickness designated by automotiveengineers.4.3 Sealant
16、Adhesive Bond ToleranceFinal bond tolerance should be 25.4 1.0 mm (1.0 0.04 in) long, 6.4 1.0 mm (0.25 0.04 in) wide, and a height of 5.0 1.0 mm (0.2 0.04 in).SAE J1836 Issued OCT88-3-4.4 Sealant Adhesive ApplicationThe sealant adhesive wet bead dimensions can be controlled to give thecured bond dim
17、ensions specified in Figure 1. The sealant adhesive shall be extruded using a 6.4 mm(0.250in) wide bead along the one in side of the elastomeric coupon. The bead should also be high enoughso that when the metal coupon is placed down on the wet sealant adhesive, the required 5 mm (0.200 in)height sha
18、ll be achieved. The sealant adhesive open time should be prescribed by adhesive supplier orautomotive engineers recommendation.4.5 Sealant Adhesive CureThe lap shear composite should remain fixed to lap shear board at humidity,temperature and time recommended by automotive engineers or adhesive supp
19、lier.4.6 Sample PreparationAfter recommended cure cycle, the lap shear specimen should be removed from theboard by cutting excess cured sealant away from the side of each lap shear specimen. This trimming willassure that the lap shear specimen will have the bond line length of 25.4 mm as described i
20、n Figure 1.4.7 ConditioningBonded lap shear specimens should be environmentally conditioned according to suppliers orautomotive engineers recommendation before being tested.5. Testing5.1 ApparatusTensile tester as described in ASTM D 1002.5.2 Sample FixtureThe sample fixture described in Figure 3 sh
21、ould be used when testing lap shear specimenson the tensile tester. The elastomeric coupon with the metal support should fit into the space provided with thelap shear specimen resting on the shoulder of the fixture. This will permit the metal or rigid coupon part tohang down to allow clamping to the
22、 lower jaw of the tensile tester.FIGURE 3FIXTURE USED FOR TESTING OVERLAPSHEAR TEST SPECIMENSAE J1836 Issued OCT88-4-5.3 Sample ClampingThe elastomeric coupon should be clamped onto the front end of the fixture to preventbending and ripping of the elastomer away from the metal support. The sample cl
23、amping distance betweenbottom edge of the elastomeric supported coupon composite in fixture and clamping jaw on metal should be 38mm (1.5 in) as illustrated in Figure 4.FIGURE 4PLACEMENT OF OVERLAP SHEAR TEST SPECIMEN INTO TEST FIXTURE5.4 Test RateLap shear specimens should be tested at a pull rate
24、of 50.8 mm (2 in)/minute.5.5 Test QuantityA minimum of five lap shear specimens should be prepared for each test condition.6. Report6.1 Complete identification and application of adhesive sealant and primer(s) used, including type andmanufacturers description.6.2 Complete Identification of the Elast
25、omeric Material6.2.1 Type of elastomeric material should be described with its generic name (such as Urethane, VINYL, etc.) andmanufacturers product identification.6.2.2 The physical properties of the material such as the elongation, tensile strength, flexural modulus, etc.6.2.3 Description of surfa
26、ce treatment such as paint, mold release, cleaning conditions, etc.6.3 Complete identification of test metal coupon or rigid substrate including thicknesses, description of rigidsubstrate and paint system.SAE J1836 Issued OCT88-5-6.4 Sample History6.4.1 Description of primers and sealant adhesives c
27、onditions before application.6.4.2 Description of open time of primers and sealant adhesives in construction of lap shear specimens.6.4.3 Description of curing history of constructed lap shear specimens.6.4.4 Environmental conditions used prior to testing such as humidity, heat age, artificial weath
28、ering, etc.6.5 Report shear strength as pounds per square inch (psi) and Newtons per square meter (Pa) by measuring bondarea.6.6 Report average of lap shear specimen values with individual lap shear values. Indicate mode of failure onindividual lap shears with estimated percentages of failure.SF . S
29、ubstrate failure of elastomeric material with descriptionCF . Cohesive failure of sealantPF . Primer failure specifying which substrateAF . Adhesive failure of sealant specifying which substratePTF Paint failure specifying which substratePREPARED BY THE SAE STATIONARY GLASS BONDING TASK FORCE OFTHE
30、SAE ADHESIVES AND BODY SEALERS COMMITTEESAE J1836 Issued OCT88RationaleNot applicable.Relationship of SAE Standard to ISO StandardNot applicable.ApplicationThis recommended practice defines a procedure for the construction of a lap shear specimen forthe purpose of testing the bondability of an autom
31、otive sealant adhesive to the elastomeric material usedin automotive encapsulating.The present practice of encapsulating automotive glass is described as molding elastomeric materialonto the outer edge of the glass using thermoplastic or thermosetting material that quickly sets in themold. The glass
32、 is removed from the mold with the cured elastomeric material bonded to the perimeterof the glass. This encapsulated glass module can now be bonded with a sealant adhesive into the bodyopening of a vehicle.Reference SectionASTMD1002Test Method for Strength Properties of Adhesives in Shear by Tension Loading (Metal-to-Metal)Developed by the SAE Stationary Glass Bonding Task ForceSponsored by the SAE Adhesives and Body Sealers Committee
