Accession Number : ADA095595


Title :   Photoelastic Studies of Internal Stress Distributions of Unidirectional Composites.


Descriptive Note : Final rept. 11 Sep 79-11 Sep 80,


Corporate Author : IIT RESEARCH INST CHICAGO IL


Personal Author(s) : Daniel,I M ; Koller,G M ; Niiro,T


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a095595.pdf


Report Date : Dec 1980


Pagination or Media Count : 55


Abstract : Two-dimensional photoelastic models were used to determine internal loading- and residual-stress distributions on the transverse cross section of unidirectional composites. The variation of residual stress was determined as a function of post-curing temperature for a room-temperature cured matrix resin. Maximum stresses and strains were determined in the matrix of a unidirectional composite with a 0.50 fiber volume ratio. Prototype composite specimens were made with the same matrix material and the same fiber volume ratio and were cured under the same conditions as the models. The transverse strength of these prototype specimens was predicted satisfactorily from results of model tests for the room-temperature cured specimens. In the case of the post-cured specimens, the predictions were higher than the measured strength. (Author)


Descriptors :   *FIBERS , *POLYMERS , *COMPOSITE MATERIALS , *MATRIX MATERIALS , *PHOTOELASTICITY , STRESSES , RATIOS , MODELS , DISTRIBUTION , TWO DIMENSIONAL , LOADS(FORCES) , PROTOTYPES , FEASIBILITY STUDIES , MODEL TESTS , INTERNAL , RESIDUAL STRESS , CURING , UNIDIRECTIONAL


Subject Categories : Laminates and Composite Materials
      Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE