PRECISION OF THE RESULTS OF STANDARD ELASTOMER-AGING TESTS

In an inter-laboratory test, the precision of the results of standardi zed ageing in air at raised temperatures was determined. It was possib le to summarize the vast amount of precision data by averaging out the not significantly different repeatability and reproducibility varianc es, and a comprehensive overview was obtained via functional relations . For hardness values before and after ageing, a repeatability. limit of 1.5 Shore A and a reproducibility limit of 2.9 Shore A were obtaine d. In the tensile test, repeatability limits from 10 to 16% and reprod ucibility limits from 15 to 25% were obtained. For property changes, r epeatability and reproducibility limits ranged between 3 and 60% accor ding to the extent of the ageing effect.