| Abstract: | It has been known for some time that crazes thicken during growth mainly by drawing in fresh material from the craze-bulk interface, keeping the average craze fibril draw ratio approximately constant. Since Creep effects contribute only negligibly to craze growth rates these effects have generally been considered unimportant regarding craze breakdown. However, it is also known that the first stage of fracture is failure of the craze midrib, which is a highly drawn, very thin region down the middle of a craze. Because of the very low thickness of the midrib it has little influence on craze behavior, and information on midrib behavior is difficult to obtain. It is the purpose of this paper to attempt to rationalize what information is available. |
