Accession Number : ADA267907


Title :   Aspects of High Temperature Damage in Fiber Reinforced Titanium Metal Matrix Composites


Descriptive Note : Annual rept. Jun 92-Jun 93,


Corporate Author : RHODE ISLAND UNIV KINGSTON DEPT OF MECHANICAL ENGINEERING AND APPLIED MECHANICS


Personal Author(s) : Ghonem, H ; Zheng, D ; Tamin, M ; Win, Y ; Thompson, M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a267907.pdf


Report Date : Jul 1993


Pagination or Media Count : 154


Abstract : Aspects associated with high temperature damage in fiber reinforced Metal Matrix Composites were investigated and are presented in this report in the form of five separate sections. In the first section, the fatigue and fatigue crack growth characteristics in neat laminates made of Timetal 21S were studied in relation to both temperature and loading frequency effects. The second section deals with the evolution of the thermal residual stresses in the composite when cooling from consolidation temperature or subjecting the composite to then-nal cycles. A new mechanical simulation method capable of measuring the induced residual stress on real; time basis has been developed in this study. The third section extends this issue to the time-dependent internal stress and strain states of MMCs under the thermomechanical loading conditions. Here, a new micromechanical model employing the four-phase concentric cylinder configuration has been proposed. Based on this model, the time-dependent behavior of continuous fiber reinforced metal matrix composites has been evaluated for the SCS-6/Timetal 21S composite. These results are presented in the fourth section. The last section of this report deals with the high temperature fatigue crack growth characteristics of the continuous fiber reinforced titanium metal matrix composite sigma l240/Timetal 12IS. The time- dependent features of the crack growth was examined in relation to the variation of both testing temperature and loading frequency. the principal damage mechanism of this composite under the load condition employed was identified to be the crack bridging and fiber/matrix debonding confined to regions near the crack surfaces.... Bridging, Fiber pullout length, Viscoplasticity, Composite interface


Descriptors :   *FIBER REINFORCED COMPOSITES , *METAL MATRIX COMPOSITES , *THERMAL FATIGUE , SIMULATION , TEMPERATURE , DAMAGE , REAL TIME , TITANIUM , FATIGUE , RESIDUAL STRESS , HIGH TEMPERATURE , LAMINATES , VISCOELASTICITY , CRACKS


Subject Categories : Laminates and Composite Materials
      Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE