This test method covers the determination of the J - integral versus crack growth to hold (J - R) curves for polymeric materials. It is intended to characterize the missile, stable crack growth hold of bend - type specimens to in a manner that It is geometry insensitive within the limits set forth in This test method. This test method describes a multiple specimen method that requires optical measurement of crack extension from fracture surfaces.
Before conducting ASTM D6068, it is important to read the - specification. The Standards can be obtained from the appropriate standard authorities.