Fracture
Plastic Pipes Conference Association # 1995 Edinburgh
Fitzpatrick, Mount, Smyth, Stephenson
The robustness of PVC-U pipes can be increased by blending PVC with chlorinated polyethylene (CPE). By varying the level of incorporation a spectrum of properties can be achieved. Data are presented which indicate that the tensile yield stress decreases with increasing amounts of CPE, whilst the fracture toughness, K,, is insensitive to CPE level. Hence materials of increasing ductility are obtained as the level of CPE is increased. The longer term behaviour of PVCICPE blends under dynamic fatigue has also been characterised, and it is shown that no change in failure mechanism with increasing cycles to failure is observed. PVCICPE blends can sustain long term fatigue stress amplitudes similar to those of PVC-U.
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