Details

Autor(en) / Beteiligte

• HILMAS, G. E
• TIEN, T.-Y

Titel

Effect of AlN and Al2O3 additions on the phase relationships and morphology of SiC. Part I. Compositions and properties

Ist Teil von

• Journal of materials science, 1999-11, Vol.34 (22), p.5605-5612

Ort / Verlag

Heidelberg: Springer

Erscheinungsjahr

1999

Link zum Volltext

Quelle

SpringerLINK Contemporary (Konsortium Baden-Württemberg)

Beschreibungen/Notizen

• X-ray diffraction was utilized to follow the transformation from β-SiC (3C) to the various α-SiC polytypes in the presence of AlN and Al2O3 additives after hot pressing from 1700 to 2100°C. The 2H- and 6H-polytypes of α-SiC were the predominate polytypes with additions of only AlN or Al2O3, respectively. The amount of 2H- and 6H-polytypes, and subsequently the microstructural morphology of the SiC materials, were found to be controlled by varying the amount of AlN and Al2O3. Improvements in fracture toughness to ∼9 MPa-√m were achieved with flexural strengths ranging from 600 to 900 MPa. These results suggest that accurate control of the polytypic make-up of SiC-based materials, along with their mechanical properties, can be achieved through AlN and Al2O3 additions.