Crazing and Degradation of Flexure Strength in Acrylic Plates as a Function of Time
Abstract
Thick acrylic plates in stressed and unstressed condition have been subjected to outdoor weathering for 10 years. The stressed specimens developed surface crazing whose extent and depth were a function of flexure stress to which they were continuously subjected. Continuously applied flexure stress of 2240 psi generated very deep crazing, which resulted in catastrophic failure of the test specimen after 9 years. On the other hand, the specimen subjected to only 810-psi flexure stress displayed no crazing. Based on our study, we conclude that for continuously stressed structural acrylic plastic components exposed to outdoor environment with 110 F maximum summer temperature, the maximum flexure design stress for a 10 year service life should not exceed 1000 psi; otherwise at the end of the service period, the remaining flexural strength of the weathered material will not provide the minimum required safety factor of 4. We also recommend that stressed acrylic plastic structures only be cleaned safely with water-based cleaners.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1989
- Accession Number
- ADA212835
Entities
People
- J. D. Stachiw
- J. L. Stachiw