The phase transformation and thermal expansion properties of cordierite ceramics prepared using drift sands to replace pure quartz

Cordierite ceramics were prepared using drift sands as the raw material instead of traditional pure quartz through solid-state sintering within an enlarged temperature range between 1100 and 1300 degrees C. The effects of adding Na2B4O7 on the phase transformation and thermal expansion coefficients were also investigated. The experimental results show that compared with pure quartz, drift sands have a lower softening temperature. Thus the sample prepared from drift sands shows a lower temperature for cordierite phase transformation, which was further reduced by adding 1.5 wt% Na2B4O7. Moreover, with an increase of Na2B4O7, the sintering temperature range was enlarged, and the amounts of the interphases of quartz and spinel as well as the thermal expansion coefficient for the obtained cordierite ceramics were decreased. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.