tensile test ASTM D 2370 tensile test ASTM D 2370 Hfadel (Civil/Environmental) (OP) 24 Sep 15 13:45 Hi i wonder does the specimen thickness affects results of tensile strength of Epoxy coating materiel when tested in accordance to ASTM D 2370 ,to get higher results test a thicker specimen ?! RE: tensile test ASTM D 2370 lukin1977 (Mechanical) 30 Sep 15 19:24 It shouldn`t affect strength result. Strength is Force/Area so if you increase thickness you get more Force but also more Area. I dont know about epoxy but for steel there is a fixed relation between diameter and initial length for elongation calculation in tensile tests. Some standards use Lo=4xDiameter and others Lo=5xdiameter. I guess that for other materials the same principle applies RE: tensile test ASTM D 2370 Compositepro (Chemical) 30 Sep 15 21:03 Many materials, and I believe this includes most paints, are sensitive to flaws and internal stresses. As a result, thicker samples usually test lower in psi than thin samples. This is why fiberglass tests far higher than bulk glass, although the properties are actually the same.