Dataset on fractographic analysis of various SiC-based fibers

Abstract

This data article reports a systematic fractographic analysis of SiC-based filaments aiming at stress intensity factors assessment. A total of 11 fiber types (as-received or chlorinated Nicalon® and Tyranno® of all three generations) where therefore repeatedly tensile tested to generate the fracture surfaces. The tensile strengths were found to be independent to defect location (surface or internal). The well-known linear square root dependence of strength on mirror, mist or hackle outer radius was reaffirmed. These measurements reveal some residual tensile stresses on Nicalon® fibers, statement however questioned by the broad data scattering. Moreover, it is shown the surface etching treatment didn't affected (generating or releasing) such residual stress. A null y-intercept was consequently adopted to assess the characteristic stress intensity factors (KIC, mirror, mist or hackle constants). The toughness (KIC) estimated this way ranges from 1.0 to 1.9 MPa m1/2 and shows a clear dependency to substrate composition: higher values were extracted on oxygen-free fibers. The Am/KIC ratio, estimated to equal 1.8 and independent to substrate type, is a key parameter that would assist further fractographic investigations.

Keywords

• SiC fiber
• Fractographic analysis
• Toughness
• Mirror