OBSERVATION AND CHARACTERIZATION OF SLOW CRACK GROWTH IN WATER PIPE GRADE POLYBUTYLENE

摘要

Polybutylene (PB) piping has been widely used in portable water distribution systems. Premature brittle fracture constitutes the major limitation for PB in its application. The fracture process of PB consists the well recognized three stages: crack initiation, slow growth and fast propagation. In present work, the observations of crack initiation in service, fatigue slow crack growth (SCG) at elevated temperature, strain localization in front of the crack constituting the process zone (PZ) as well as variability of the strength of PB are reported.