In this study, coarse magnetite (>63 μm) is introduced as a reactive component in wollastonite-based chemically
bonded phosphate ceramics (WPC). It is found that WPC with coarse magnetite results in the formation of new
stable microstructural phases such as iron phosphate cementitious matrix. The new ceramics (M-WCP) exhibit
much lower shrinkage than WPC even after heating at elevated temperatures —eight times less shrinkage at
200 ◦C. Stiffness increases sharply from the 11.4 GPa of WPC to 23.4 GPa by adding coarse magnetite filler (MWPC).
The stiffness of WPC is reduced by more than 50% by heating above 100 ◦C, while M-WPC preserves more
than 70% of its stiffness when heated up to 700 ◦C. Compressive strength increases from the 52 MPa of WPC, up
to 80 MPa (M-WPC) by introducing coarse magnetite as reactive component. The new iron phosphate cementitious
material —with attractive microstructural and mechanical properties besides high dimensional and
thermal stability— can be recommended for many applications in construction, waste stabilization, and storage
systems for radioactive materials.

Title

Journal of Physics and Chemistry of Solids

Publisher

elsevier

Publisher Country

Netherlands

Indexing

Thomson Reuters

Impact Factor

3.995

Publication Type

Both (Printed and Online)

Volume

162

Year

2021

Pages

110531