Abstract:

A novel method of reaction sintering combined with hot-pressing technology was developed to prepare Li2Si2O5 glassceramics with high flexural strength and fracture toughness. Li2SiO3 crystal, SiO2 and Li2Si2O5 glass were used as the starting powders. The results show that via an interaction between Li2SiO3 crystals and SiO2 glass, rod-like Li2Si2O5 crystals with length of up to tens microns could be obtained, which were several times longer than those directly crystallized from the Li2Si2O5 parent glass. Through adjusting the Li2Si2O5 glass content, Li2Si2O5 glass-ceramics displayed a denser microstructure with the bimodal distribution consisting of large elongated Li2Si2O5 grains formed during the reaction and smaller precipitates of the Li2Si2O5 glass powder. Although the crystallinity decreased with increasing the Li2Si2O5 glass content, the Li2Si2O5 glass-ceramics exhibited high flexural strength (350 ± 13 MPa) and high fracture toughness (3.3 ± 0.14 MPa·m1/2).