Scope:

The ASTM D2095 test technique specifies the use of bar-and rod-shaped butt-joined specimens  to determine the relative tensile strength of adhesives. This test method can be used to evaluate  adhesives using a variety of adherend materials in similar or distinct combinations. Specification  acceptance, service evaluation, manufacturing control, research, and development all may benefit  from tensile strength data. 

The tests look at not only the adhesive’s intrinsic strength, but also the bonding technique,  surface cleanliness, the efficacy of surface treatments, surface etchings, adhesive application and  coverage, and the curing cycle.

Procedure:

For the ASTM D2905 test, the specimen is loaded into the testing machine using steel dowel pins and fixtures. The test is carried out at a temperature different from room temperature in a  temperature-controlled test chamber that encloses the fixtures and the test specimen in the testing  machine. The load is applied to the specimen at a rate of 17 to 20 MPa/cm²(2400 to 2800 psi) of  bond area per min for speed testing. The testing machine is set to get the foregoing rate of  loading if the rate of loading is measured as crosshead motion. At the time of failure, the maximum load carried by the specimen is recorded. By visual inspection, the percentage cohesion failure, adhesion failure, contact failure, and adherend failure based on the bond area is calculated and recorded. 

Video 01: Measuring the tensile strength of adhesives 

Specimen size:

Bar-and rod-shaped butt-joined specimens are used in the ASTM D2095 test method.

Data:

For ASTM D2095, the tensile strength is calculated by dividing the breaking load by the area of the bonded surface. The result is expressed in megapascals per square centimeter (pounds per square inch).

Conclusion:

The ASTM D2095 test technique specifies the use of bar-and rod-shaped butt-joined specimens to determine the relative tensile strength of adhesives.