PROGRESSIVE FRACTURE SIMULATION OF SATIN WEAVE COMPOSITE STRUCTURES

摘要

Progressive fracture of satin weave composites is modeled using a computational synthesis method to assemble the anisotropic satin weave properties from the constituent woven and straight fiber composite properties and the satin weave pattern. Once the structural properties are assembled, the composite structure is analyzed and the generalized satin weave stresses and strains are computed. Damage is assessed for the plies and braids of the satin weave subsystems. The effects of damage on the residual stiffness properties of the anisotropic satin weave composite are quantified. Computational simulation is applied to the simulation of a satin weave ceramic matrix composite structure. The static tensile, creep and fatigue response of the N720/A ceramic composite system are simulated at three temperatures using the GENOA-PFA computational procedure. The constituent fiber and matrix properties are identified for characterizing static tensile, creep, and fatigue strengths at room temperature, and also at elevated temperatures of 1100°C and 1200°C. Sensitivity of the satin weave ceramic composite to variability in the constituent properties is assessed using the probabilistic-based sensitivity module available in GENOA. Results show the damage progression sequence and the changes in the structural response characteristics during different degradation stages. Conclusions include determination of sensitive parameters affecting damage progression, and interpretation of experimental results with insight for design decisions for satin weave composites. Effect of matrix void content on load response is demonstrated. Results show effects of significant manufacturing parameters on structural durability, damage initiation, damage tolerance and ultimate strength of woven CMC composites.