Densification route and mechanical properties of Si3N4-bioglass biocomposites

• Type: Article in International Scientific Journal
• Date: 2002

Authors

M. Amaral (Author) Other; Maria Ascensão Lopes (Author) FEUP; R. F. Silva (Author) Other; José Domingos Santos (Author) FEUP

Journal

Title: Biomaterials

Vol. 23 No. 24

Pages: 857-862

ISSN: 0142-9612

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 50 Citations

ISI Web of Science

Scopus - 68 Citations

COMPENDEX

Scientific classification

FOS: Engineering and technology > Environmental biotechnology

Other information

Authenticus ID: P-000-QBS

DOI: 10.1016/s0142-9612(01)00194-6

Abstract (EN): The processing route and the final microstructural and mechanical characteristics of a Nobel biomaterial composite are described, This new material is composed of 70 wt% Si3N4 ceramic phase and 30 wt% bioglass, the later performing as a liquid sintering aid system and simultaneously providing bioactivity characteristics to the composite. The conditions for fabrication of an almost fully dense material (similar to 98% of relative density) were pursued. Optimised parameters were 1350 degreesC-40 min-30 MPa by hot-pressing technique, The very fast densification rate of the process avoided the crystallisation of the bioglass intergranular phase and therefore its intrinsic properties were maintained. Also, the large amount of glassy phase assured the densification by liquid phase assisted grain rearrangement Without Si3N4 Phase transformation. The final mechanical properties of the Si3N4-bioglass were as follows: fracture toughness. K-IC = 4.4 MPa m(1/2). Vickers hardness. H-V = 10.3 GPa, Young's modulus, E = 197 GPa; bending strength, sigma (R) = 383 MPa, Weibull modulus, m = 8.3. These values provide an attractive set of properties among other bioactive materials, namely by upgrading the main drawback of bioceramics and bioglasses for high-load medical applications, which is the lack of satisfactory fracture toughness.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6