Thermal expansion behavior and macrostrain of Al2O3/Al composites with interpenetrating networks

✍ Scribed by S. Skirl; M. Hoffman; K. Bowman; S. Wiederhorn; J. Rödel

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 932 KB
• Volume: 46
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/s1359-6454(98)80033-5

✦ Synopsis

The aim of the study is to investigate the thermal expansion behavior and internal residual strains in metal reinforced ceramic matrix composites (CMCs). A variety of A&Oj/Al CMCs with an interpenetrating network structure were produced using a pressure infiltration technique. The samples contained two variations in the average ligament diameter of the metal phase of 0.15 pm and 1 pm and metal contents ranging from 13 to 40 vol.%. Coefficients of thermal expansion (CTEs) were found to vary significantly with temperature.

It is proposed that this indicates an influence of the flow characteristics of the metal. Comparisons are made with well known methods for predicting CTEs of metal/ceramic composites. Overall strain increases with temperature scaled proportionally with metal content. Comparisons were made with uninfiltrated porous ceramic preforms and a pure metal sample. Hysteresis was observed between the heating and cooling of the composite samples at constant rate. 0 1998 Acta Metallurgica Inc.