The effect of powder properties on sintering, microstructure, mechanical strength and degradability of beta-tricalcium phosphate/calcium silicate composite bioceramics

Biomed Mater. 2009 Dec;4(6):065009. doi: 10.1088/1748-6041/4/6/065009.

Abstract

The effect of powder properties on sintering, microstructure, mechanical strength and degradability of beta-tricalcium phosphate/calcium silicate (beta-Ca3(PO4)2/CaSiO3, beta-TCP/CS) composite bioceramics was investigated. beta-TCP/CS composite powders with a weight ratio of 50:50 were prepared by three different methods: mechanical milling method (TW-A), two-step chemical precipitation method (TW-B) and in situ chemical co-precipitation method (TW-C), and then the three composite powders were uniaxially compacted at 30 MPa, followed by cold isostatic pressing into rectangular-prism-shaped specimens under a pressure of 200 MPa for 15 min, and then sintered at 1150 degrees C for 5 h. The TW-B powders with less agglomerative morphologies and uniform nano-size particles attained 96.14% relative density (RD). A uniform microstructure with about 120 nm grains was observed. Whereas, the samples obtained from TW-A and TW-C powders only reached a RD of 63.08% and 78.86%, respectively. The bending strength of the samples fabricated from TW-B reached 125 MPa, which was more than 3.7 and 1.5 times higher as compared with that of samples obtained from TW-A and TW-C powders, respectively. Furthermore, the degradability of the samples fabricated from TW-B powders was obviously lower than that of the samples fabricated from TW-A and TW-C powders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biocompatible Materials / chemistry*
  • Bone Substitutes*
  • Buffers
  • Calcium Compounds / chemistry*
  • Calcium Phosphates / chemistry*
  • Compressive Strength
  • Materials Testing
  • Microscopy, Electron, Scanning / methods
  • Nanoparticles / chemistry
  • Nanotechnology / methods
  • Porosity
  • Powders
  • Silicates / chemistry*
  • Stress, Mechanical
  • Surface Properties
  • X-Ray Diffraction

Substances

  • Biocompatible Materials
  • Bone Substitutes
  • Buffers
  • Calcium Compounds
  • Calcium Phosphates
  • Powders
  • Silicates
  • beta-tricalcium phosphate
  • calcium silicate