Bond Strength ASTM D1002 Testing

Standard Test Method for Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Tension Loading (Metal-to Metal)

ASTM D1002 Test Method

The ASTM D1002 test method is one of the most common test methods used to determine the bond strength of adhesives when tested on a single-lap-joint specimen on a metal to metal bonded test panel. Similar test methods are ASTM D3163 (Rigid Plastics) and ASTM D3164 (Plastic & Metal Substrates). Each test method uses a sample that is bonded together via a single lap shear joint. The standard specifies the following parameters to ensure accurate and consistent testing;

• The manufacturer of the adhesive will specify the conditions under which the specimen is prepared, unless otherwise agreed upon by the manufacturer and the purchaser.
• The manufacturer is required to supply specific information as it relates to the following;
• Surface preparation procedure
• Mixing directions for the adhesive being used to bond the samples
• Detailed adhesive application procedures (Thickness, number of coats, rate of spread)
• Detailed test sample assembly conditions (Temperature, humidity, etc.)
• Curing conditions (Pressure applied, method of pressure application, etc.)

Sample conditioning prior to testing (Room temperature ranges, humidity ranges, etc.)

Test Frame, Grips and Accessories

United manufactures and supplies a wide range of Universal Test Machines, grips, fixtures and accessories to help you perform ASTM D1002.

Universal Test Machines are differentiated by capacity and choosing the proper test frame is determined by how much force is required to break the sample, in this case two metal test panels that have been glued together.

If you are unsure how much capacity is required for your test, United will perform a free sample test to help you determine system capacity requirements. You should also discuss capacity requirements with the manufacturer of the adhesive to ensure the system you choose will provide enough capacity to break the samples being tested.

United offers Universal Test Machines that range in capacity from our single-column 2.5kN (550 Lbf) up to 600kN (449,000 Lbf) dual-column frames. Dual column frames are available as both table model or floor model systems.

The ASTM D1002 standard itself specifies that the test apparatus, grips, and accessories provide the following;

Test Frame

• The testing machine shall conform to the requirements of Practices E4, which all United test frames comply with.
• The capacity of the testing machine shall be rated such that it falls between 15% and 85% of the breaking load of the specimens being tested.
• The machine shall be capable of maintaining a rate of loading of 80 to 100 kg/cm2 (1200 to 1400 psi)/min, or, if the rate is dependent on crosshead motion, the machine should be set to approach this rate of loading, approximately 0.05 in./min, which all United test frames comply with.

Grips

• A suitable pair of self-aligning grips to hold the specimen.
• It is recommended that the jaws of these grips shall engage the outer 25 mm (1 in.) of each end of the test specimen firmly.
• United generally recommends either our A-Series Wedge Grips, or our DA-Series Wedge Grips with the appropriate serrated jaw inserts the match the samples being tested.

Load cell

ASTM D1002 does not specify load cell accuracy requirements, but virtually all modern load cells supplied with UTM’s will accurately measure the tensile forces required to break the samples.

Test Specimens

Specific test specimen dimensions should be obtained directly from the standard. It is important to note that if your testing procedure results in failure of the metal as opposed to failure of the adhesive a thicker metal sample should be used, or the area over which the adhesive is applied should be modified. The exact dimensions of this area can be obtained from the ASTM D1002 standard.

Test Calculations and Reporting

The load at failure should be recorded and results should be expressed in kilograms per square centimeter (pounds per square inch, PSI) of shear area. This is important to note because simply recording the peak force in terms of Newtons, Kilonewtons, or Pound-force is not enough to satisfy the standard.

While this calculation could be performed manually, United’s DragonFly UTS software along with one of our Universal Test Machines is fully capable of performing the ASTM D1002 test procedure and expressing the results as specified in the standard.

Each United Universal Test Machine includes the test frame, loadcell, Windows PC, software, and the pre-written ASTM D1002 test procedure to get you up and running quickly. Custom or modified test procedures can also easily be written. Presentation quality test reports displaying all necessary calculations are available immediately and data is stored a secure and easy to search Access database.

Conclusion

United has done virtually all the work for our customers when it comes to performing the ASTM D1002 test procedure. All customers need to do is determine which sample type they will be testing so we can choose the proper test frame capacity and grips.

View our Adhesion testing machines here

Reference links;

http://www.astm.org/cgi-bin/resolver.cgi?D1002-10(2019)

ASTM D1002-10(2019), Standard Test Method for Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Tension Loading (Metal-to-Metal), ASTM International, West Conshohocken, PA, 2019, www.astm.org