Continuous Oxide Filament Synthesis (Devitrification).
Abstract
Studies to produce continuous polycrystalline aluminum oxide filaments by vacuo-thermal conversion of precursor aluminum-boro-phosphate glass filaments are described. A field of compositions in the ternary Al2O3.B2O3.P2O5 system containing up to 60 percent alumina was identified from which glass melts could be produced and filaments drawn. Thoria and yttria additions to the glasses extend their working range and reduce their tendency to devitrify. Macrowarpage and microkinking associated with the thermal conversion were eliminated by tensioning the filaments. Tensile strengths of the filaments produced were approximately one-third of that sought. The critical factors limiting strength in this region were not associated with grain size or internal porosity, but were likely associated with the nature of the filament surface. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1971
- Accession Number
- AD0728667
Entities
People
- Frederick H. Simpson
Organizations
- Boeing