Effects of ZrO2 on Zinc Crystalline Glaze

Zinc Crystal Glaze has its limits in practical use of commercial glaze due to the sensitive firing schedule. In order to overcome these limits, and to improve the practical usage, this study is aimed to develop a stable zinc crystalline glaze. This study altered the quantity of nuclear formation of zinc crystal glaze in order to control the willemite (Zn2SiO4) formation in the glaze. The addition of ZrO2 to zinc crystal glaze influences the quantity of nuclear formation and its preservation; thus ZrO2 was used to control the optimal firing temperature and the size of the crystal formation in the glaze to find a zinc crystal glaze capable of withstanding various ranges of temperatures.

Effect of Nanosized Particles on the Mechanical Properties of Y2O3

A systematic series of experiments was performed to determine the optimum firing schedule of Y2O3. A two-step sintering with subsequent profile succeeded to fabricate Y2O3 ceramic with the relative density of 97.6% and the average grain size of 0.46 μm: first step and second step temperature of T1 = 1490 °C and T2 = 1350 °C, respectively and second step holding time of t2 = 20 h. After the firing schedule of pure Y2O3 was determined, two types of TiO2/Y2O3 and ZrO2/Y2O3 composites were fabricated for the further improvement of mechanical properties. According to results, ZrO2/Y2O3 composite showed a dramatic increase in strength and toughness as 417 MPa and 4.4 MPa.m1/2, respectively.

Study on Effect of Lattice Distortion on Infrared Properties of Ceramic Tiles at Ambient Temperature

Effect of the lattice distortion of the main crystal mullite, addition of copper mine tailing and the firing schedule on the infrared properties were studied. The study revealed that the higher lattice distortion is, the higher infrared emissivity of ceramic tiles is. The addition of raw materials containing iron and other elemental impurities could form the solid solution in the body what promote the degree of lattice distortion of main crystal which affects the infrared emissivity of the ceramic tiles. With the increasing of firing temperature, the degree of lattice distortion of main crystals will decrease and the infrared properties also decrease.

On the Multilayered Chip-Type PTC Elements Prepared by Roll-Forming Process

We describe the fabrication of chip-type PTC elements (BaTiO3-based) by roll-forming process. Crack-free green tapes with good malleability are successfully obtained with the thickness typically in the range of 0.20~1.0mm. We also focus on reducing the room-temperature resistance of the chip-type PTC element without deteriorating its PTC effect, both by controlling the firing schedule and by introducing multilayer structure with electrode-bonding method. The typical size of the 5-layered chip-type PTC sample obtained is 8.0mm×5.0mm×1.95mm with R25=1.97- and Rmax/Rmin=4.8×105.