1、 FORD LABORATORY TEST METHOD BV 101-07 Date Action Revisions 2002 01 10 Revised Editorial no technical change A. Cockman 2000 03 02 Revised Editorial no technical change A. Cockman 1994 10 12 Printed copies are uncontrolled Page 1 of 21 Copyright 2002, Ford Global Technologies, Inc. STRESS DURABILIT
2、Y TEST FOR ADHESIVE LAP-SHEAR BONDS Application This method is used to evaluate the relative performance of adhesive bonding systems exposed to simultaneous tensile load and environment. The corrosion option is designed to simulate the corrosive conditions of the Arizona Proving Ground (APG) Vehicle
3、 Accelerated Corrosion Test (P3-76A). Apparatus Required Stress Durability Fixtures A set of fixtures made of stainless steel (Figure 1), 635 mm stainless steel bolts, 19.05 mm long with nuts, and nylon washers with 6.35 mm holes, 19.05 mm diameter. Die springs for the fixtures should have an ID of
4、19.3 mm, a length of 127 mm, and a spring rate approximately 15 kg/mm. These fixtures are not commercially available and should be constructed per the attached drawings. Compression Testing Instrument An Instron tensile testing machine or equivalent in compression mode with an accuracy of 0.5 % of t
5、he range used. Modified Vise A vise of sufficient size as to hold the stress durability fixture and compress the spring. The grips of the vise must be modified to accommodate the fixture (Figure 2). An Armstrong 12.7 cm machinist bench vise is adequate. Test Coupons, Blanks and End Tabs Test coupons
6、 shall be 25 x 56.25 mm x t where t is the specified thickness of the substrate (Figure 3). The blanks shall be of the same material as the substrate used unless otherwise specified and shall be 25 x 100 mm x t where t is the specified thickness of the substrate. The end tabs are to be the same as t
7、he blanks except that the length is to be 52 mm instead of 100 mm (Figure 4). Humidity Cabinet Humidity cabinet, with forced air circulation, temperature control of +/-2 C up to 65 C, and relative humidity control of +/- 0.5 % up to 90 %. Tank Polyethylene or plastic lined tank, with cover, of suffi
8、cient size and capacity to permit the stress durability fixtures to be immersed in the salt solution to a level covering the top test specimen. For the stress durability fixtures outlined above a 120 liter or equivalent polyethylene trash can is adequate. FORD LABORATORY TEST METHOD BV 101-07 Page 2
9、 of 21 Copyright 2002, Ford Global Technologies, Inc. Drying Rack A rack for drying the stress durability fixtures such that the fixtures are maintained in a vertical position. Tensile Testing Instrument An Instron tensile testing machine or equivalent in tensile mode with an accuracy of 0.5 % of th
10、e range used. Materials Required Sodium Chloride Reagent grade. Distilled or Deionized Water 10 ppm maximum dissolved solids per ASTM D 1888. Hydrochloric Acid Reagent grade. Sodium Hydroxide Reagent grade. Glass Beads Solid glass beads to control bond line thickness can be obtained from Cataphote I
11、nc., Jackson, Mississippi. It is the responsibility of the requestor to define the desired diameter. However, a commonly employed glass bead diameter for metal to metal bonding is 0.25 +/- .01 mm. Occasionally, 0.75 +/- .01 mm diameter glass beads are used especially for bonding composite to composi
12、te. Substrate Type, thickness, contamination, treatment, and cleaning obtained from requestor. Adhesive Material and cure conditions obtained from requestor. Conditioning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/- 2 C a
13、nd 50 +/- 5 % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. FORD LABORATORY TEST METHOD BV 101-07 Page 3 of 21 Copyright 2002, Ford Global Technologies, Inc. Procedure 1. This test method requires the preparation of 4 lap-s
14、hear coupons for initial unexposed load to failure and 6 lap-shear coupons for each load/ environment combination. Prepare lap-shear test coupons as in Figure 5. The coupon overlap is 12.5 mm, the width is 25 mm, and the bondline thickness is maintained with glass beads. Remove squeeze-out with squa
15、re edge spatula. Cure assembled coupons per adhesive manufacturers recommendations. All of the above shall be done as indicated unless other-wise specified by requestor. Punch 6.35 mm holes in ends of coupons except for coupons to be pulled for initial failure load. Condition samples 24 h at ambient
16、 conditions prior to any testing. 2. Initial tensile testing involves placing bonded coupons in the grips of the tensile testing machine so that the grips hold on to 20 mm of the ends of the coupons. For thick substrates, shims should be used in the grips to keep proper alignment of the specimen. Pu
17、ll coupons at a constant strain rate of 10 mm per minute. Measure peak load to failure (kN). 3. Bolt coupons together with stainless steel bolts and nylon washers alternating the arrangement of each joint as to keep the bondline aligned along the center of the fixture (Figure 1). Also bolt the end t
18、abs on to the string of coupons. 4. Calibrate springs by measuring the compressed spring length for the desired load. Record spring ID, load (kg), and compressed length (mm). The loads for the testing are to be defined by the requestor. Loads for testing are to be reported as absolute values and as
19、fractions of initial strength as determined in Step 2. 5. Assemble stress fixtures. Load strings of coupons in stress durability fixtures. Compress spring to the desired compression length in the modified vise, see Figure 6. Screw down nut on top of fixture. To avoid twisting of the test specimens,
20、it is essential to compress the spring and tighten the nut with the stress fixture in the vise. DO NOT TORQUE DOWN ON THE NUT OUTSIDE OF THE VISE. Release vise. Check compression length. Repeat compression steps until desired length is obtained in the released position. 6. Periodically check displac
21、ement of springs. Check daily for the first 10 cycles and thereafter check every 5 cycles. 7. Environmental exposure: For static humidity exposure follow steps 8 and skip to step 14. For cyclic corrosion exposure follow steps 9 through 14. The basis for this cyclic corrosion procedure is taken from
22、FLTM BI 123-01 Painted Sheet Metal Corrosion Test (Laboratory-Simulated Arizona Proving Ground Test). FORD LABORATORY TEST METHOD BV 101-07 Page 4 of 21 Copyright 2002, Ford Global Technologies, Inc. 8. Place stress durability fixtures vertically in the temperature/humidity cabinet at 50 +/- 2 C and
23、 90 +/- 5 % relative humidity for testing. If possible keep the spring out of the humidity cabinet while allowing the samples to be exposed to the environment. On a daily basis check for failure of coupons (see step 14). 9. Prepare a 5 % salt solution as follows: Dissolve 53 g of sodium chloride per
24、 liter of distilled or deionized water. Prepare a sufficient amount to allow for complete immersion of test coupons contained in the stress durability fixtures. Adjust the solution pH to 6.0 - 8.0 by the addition of sodium hydroxide or hydrochloric acid. Replace salt solution and clean out tank when
25、 appreciable residue accumulates in the bath or when the pH is outside the 6.0 - 8.0 range (do not readjust the pH). 10. Begin the first test cycle on a Monday morning. Immerse the samples in the 5 % sodium chloride solution at 23 +/- 2 C for 15 minutes. Care should be taken not to get salt solution
26、 on the springs. 11. Remove fixtures from salt solution, drip dry vertically at 23 +/- 2 C for 105 minutes. 12. Place stress durability fixtures vertically in the temperature/humidity cabinet at 50 +/- 2 C and 90 +/- 5 % relative humidity for 22 h. If possible keep the spring out of the cabinet whil
27、e allowing the samples to be exposed to the environment. On a daily basis check for failure of coupons. 13. Repeat steps 10 through 12 every 24 hours, Monday through Friday. During weekends and holidays leave the specimens in the temperature/humidity cabinet at 50 +/- 2 C and 90 +/- 5 % relative hum
28、idity. Note: One test cycle is completed after performing steps 10 through 12. There is a maximum of 5 cycles per week. 14. When failure occurs: Take out failed coupon, replace with blank, and reload fixture (see step 5). When 4 of the 6 coupons have failed the testing is complete. Report 1. Adhesiv
29、e identification including: Manufacturer, code number, type, date manufactured, etc. FORD LABORATORY TEST METHOD BV 101-07 Page 5 of 21 Copyright 2002, Ford Global Technologies, Inc. 2. Substrate identification including: Manufacturer, code number, type, thickness, treatment, contamination, cleaning
30、, etc. 3. Bond geometry including: Bondline thickness, overlap length, bond width. 4. Conditioning procedure for specimens prior to testing. 5. Initial loads to failure (peak load (kN) for each substrate/adhesive combination, average and standard deviation. 6. Stress durability exposure conditions:
31、APGE cyclic corrosion, static humidity (temperature/relative humidity), or other. 7. Time to failure (cycles APGE or days static humidity) for each specimen, and total number of specimens tested (including number of unfailed specimens and number and time of termination of specimens removed prior to
32、the conclusion of the test). 8. Specimen location in fixture (sample 1 top through sample 6 at bottom). 9. Estimated failure loci percentages: Cohesive with adhesive, interfacial between adhesive and substrate, substrate failure, or other. Chemicals, materials, parts, and equipment referenced in thi
33、s document must be used and handled properly. Each party is responsible for determining proper use and handling in its facilities. FORD LABORATORY TEST METHOD BV 101-07 Page 6 of 21 Copyright 2002, Ford Global Technologies, Inc. LIST OF FIGURES Figure 1 Assembly - Humidity Cabinet Lap Shear Test Fix
34、ture RAD/XRL-641A Figure 1a Washer - Humidity Cabinet Lap Shear Test Fixture RAD/XRL-642 Figure 1b Threaded Rod - Humidity Cabinet Lap Shear Test Fixture RAD/XRL-643 Figure 1c Spring - Humidity Cabinet Lap Shear Text Fixture RAD/XRL-644 Figure 1d End Cap - Humidity Cabinet Lap Shear Text Fixture RAD
35、/XRL-645 Figure 1e Tube - Humidity Cabinet Lap Shear Text Fixture RAD/XRL-646 Figure 1f Adj. End Block - Humidity Cabinet Lap Shear Text Fixture RAD/XRL-648 Figure 1g Fixed End Block - Humidity Cabinet Lap Shear Text Fixture RAD/XRL-651 Figure 1h Assembly - Adjustable End Block RAD/XRL-686 Figure 2a
36、 Moveable Jaw - Spring Compressing Vise RAD/XRL-659 Figure 2b Fixed Jaw - Spring Compressing Vise RAD/XRL-652 Figure 3 Test Coupon - Humidity Cabinet Lap Shear Text Fixture RAD/XRL-649 Figure 4 End Link - Humidity Cabinet Lap Shear Text Fixture RAD/XRL-647C Figure 5 Assembly - Lap Shear Coupon RAD/X
37、RL-650 Figure 6 Load Setting - Humidity Cabinet Lap Shear Text Fixture RAD/XRL-658 FORD LABORATORY TEST METHOD BV 101-07 Page 7 of 21 Copyright 2002, Ford Global Technologies, Inc. Figure 1 FORD LABORATORY TEST METHOD BV 101-07 Page 8 of 21 Copyright 2002, Ford Global Technologies, Inc. Figure 1a FO
38、RD LABORATORY TEST METHOD BV 101-07 Page 9 of 21 Copyright 2002, Ford Global Technologies, Inc. Figure 1b FORD LABORATORY TEST METHOD BV 101-07 Page 10 of 21 Copyright 2002, Ford Global Technologies, Inc. Figure 1c FORD LABORATORY TEST METHOD BV 101-07 Page 11 of 21 Copyright 2002, Ford Global Techn
39、ologies, Inc. Figure 1d FORD LABORATORY TEST METHOD BV 101-07 Page 12 of 21 Copyright 2002, Ford Global Technologies, Inc. FORD LABORATORY TEST METHOD BV 101-07 Page 13 of 21 Copyright 2002, Ford Global Technologies, Inc. Figure 1f FORD LABORATORY TEST METHOD BV 101-07 Page 14 of 21 Copyright 2002,
40、Ford Global Technologies, Inc. Figure 1g FORD LABORATORY TEST METHOD BV 101-07 Page 15 of 21 Copyright 2002, Ford Global Technologies, Inc. FORD LABORATORY TEST METHOD BV 101-07 Page 16 of 21 Copyright 2002, Ford Global Technologies, Inc. FORD LABORATORY TEST METHOD BV 101-07 Page 17 of 21 Copyright
41、 2002, Ford Global Technologies, Inc. FORD LABORATORY TEST METHOD BV 101-07 Page 18 of 21 Copyright 2002, Ford Global Technologies, Inc. FORD LABORATORY TEST METHOD BV 101-07 Page 19 of 21 Copyright 2002, Ford Global Technologies, Inc. FORD LABORATORY TEST METHOD BV 101-07 Page 20 of 21 Copyright 2002, Ford Global Technologies, Inc. FORD LABORATORY TEST METHOD BV 101-07 Page 21 of 21 Copyright 2002, Ford Global Technologies, Inc.
