Thermal Behavior and Determination of the Heated Structure of 11ÅAnomalous Tobermorite by in situ X-ray Diffraction  

作　　者：YAN Yu WANG Hejing 

机构地区：[1]School of Earth and Space Sciences,Peking University,Beijing 100871,China [2]Key Laboratory of Orogenic Belt and Crustal Evolution,Ministry of Education,Beijing 100871,China

出　　处：《Acta Geologica Sinica(English Edition)》2021年第3期810-829,共20页地质学报（英文版）

摘　　要：This article presents the thermal transitions of a tobermorite-bearing sample when heated from 30℃ up to 1200℃,both in vacuum and in static air,including tobermorite transforming to wollastonite,aragonite to calcite and calcite to lime.Characteristics obtained by in situ high temperature X-ray diffraction,field emission scanning electron microscopy and scanning transmission electron microscopy analyses jointly indicate that the investigated tobermorite is anomalous.The variations along the a,b,c axes and the volume changes of tobermorite with increasing temperature are described,and its thermal shrinkage coefficients therefore determined.The comparison between the refined structures at 30℃ and 800℃ demonstrates that the shrinkage degree(Δa/a0)along the a axis is higher than those(Δb/b0,Δc/c0)along the b and c axes.The wollastonite is formed in two ways:Tobermorite converting to wollastonite and lime reacting with quartz to form wollastonite.

关 键 词：TOBERMORITE in situ X-ray diffraction phase transition thermal shrinkage WOLLASTONITE 

分 类 号：TU52[建筑科学—建筑技术科学] P584[天文地球—岩石学]