| Abstract: | Biaxially oriented PMM is shown to have important advantages as a structural material over unoriented PMM owing to a difference in fracture kinetics. Under identical conditions primary cracks appear later in the oriented PMM, their growth is impeded, and the rate of crack propagation in the avalanche stage of failure is much lower. This accounts for the greater resistance of biaxially oriented PMM to stress raisers and its higher fracture energy under biaxial loading.All-Union Scientific-Research Institute of Aviation Materials, Moscow. Translated from Mekhanika Polimerov, Vol. 5, No. 2, pp. 274–281, March–April, 1969. |
