ASTM D1876 is a test method that measures the peel separation strength of two flexible materials that have been bonded together. This is commonly referred to as the “T-Peel” test because the sample looks like the letter “T” when loaded in the machine before the test. Other common peel tests are the 90 degree and 180 degree peel test but they are used when a flexible material has been bonded to a rigid substrate such as plastic or metal. The load vs. position graph will look similar to other peel tests whereby there is a force spike recorded initially followed (hopefully) by a consistent force reading throughout the rest of the peel. The reported measurement is occasionally the maximum force but most often the average force of a few inches of peel divided by the width of the sample.
Prior to conducting ASTM D1876, it is important to read the entire specification in the relevant ASTM publication.
Load each end of the sample into opposing tensile grips.
Begin grip separation at the constant rate of speed defined in the specification and end after enough material has been peeled to cover the distance of your average force analysis.
Report the maximum force and average force per unit width of the sample. The average should be set to ignore the beginning of the test (0.5” or 1”) so as not to include the initial force spike occurring in this region.