Sintering Li2O–Al2O3–4SiO2 precursor powders with ultrafine TiO2 additives

β-Spodumene (Li2O–Al2O3–4SiO2, LAS) powders have been synthesized by a sol–gel process using Si(OC2H5)4, Al(OC4H9)3 and LiNO3 as starting material and TiO2 as a sintering aid. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron diffraction (ED) analysis were utilized to study the sintering β-spodumene precursor powders with ultrafine TiO2 additives. Densification has not been completed during sintering at 1350 °C for 5 h for the LAS precursor powers added with 5.0 wt.% TiO2. These sintered bodies contain β-spodumene as a main phase and a small amount of rutile TiO2. β-Spodumene grains tend to coalesce to greater than 20.0 μm in size, while the rutile TiO2 phase segregates at the grain boundaries of β-spodumene grains. The TiO2 addition in the sintering of β-spodumene precursor powders has a tendency to inhibit the transformation of an amorphous LAS precursor to β-spodumene.