Crystallisation of Ba1-xSrxZn2Si2O7 from BaO/SrO/ZnO/SiO2 glass with different ZrO2 and TiO2 concentrations

Solid solutions based on BaZn2Si2O7 with thermal expansions from negative to highly positive – a review

“…17 shows the microstructure of a glass–ceramic with the composition 7.5 BaO·7.5 SrO·34 ZnO·43 SiO 2 ·7 ZrO 2 ·1 TiO 2 crystallized at 750 °C for 48 h and at 840 °C for 30 min. 63 Large crystals within the glass volume can be found, which seem to start growing from only one nucleus. Furthermore, crystal agglomerates of the Ba 0.5 Sr 0.5 Zn 2 Si 2 O 7 phase with diameters in the range from 40 to 60 μm are observed.…”

“…As oxidic nucleation agents, comparatively high ZrO 2 concentrations of ≥6 mol% can be used. 62,63 Additionally, P 2 O 5 , 64 Furthermore, the crystallization of (Ba,Sr) 5 (PO 4 ) 3 Cl, a phase with the hexagonal apatite (Ca 5 P 3 O 12 OH) structure (space group P6 3 /m), occurred (see the bright crystals with hexagonal shape in Fig. 18).…”

“…As oxidic nucleation agents, comparatively high ZrO 2 concentrations of ≥6 mol% can be used. 62,63 Additionally, P 2 O 5 64 , both P 2 O 5 and Ce 2 O 3 65 , WO 3 66 and Ta 2 O 5 67 were reported to act as nucleation agents. It should be noted that the oxidic nucleation agents up to now reported in the literature for these glass systems are by far not as effective as the noble metals.…”

“…As oxidic nucleation agents, comparatively high ZrO 2 concentrations of ≥6 mol% can be used. 62,63 Additionally, P 2 O 5 , 64 both P 2 O 5 and Ce 2 O 3 , 65 WO 3 (ref. 66) and Ta 2 O 5 (ref.…”

Role of Tin Oxide as a Nucleating Agent with Low Solubility in BaO–SrO–ZnO–SiO2 Glasses Studied by Electron and X-ray Microscopy

“…In order to achieve volume crystallization with homogeneously dispersed crystals in the sub-micrometer range, nucleation agents have to be evaluated. The commonly known ones, such as TiO 2 ZrO 2 or metallic gold, do not work satisfactorily within this glass system. − Therefore, this work focuses on the effect of SnO 2 on the crystallization behavior with an emphasis on the microstructure as well as thermal expansion behavior.…”