| 研究実績の概要 |
To evaluate adhesive strength between the embedded and fused zirconia beads (B53 and B125) and the zirconia bulk, stainless steel rods with 4 mm diameter was bond to the rough surface of the zirconia substrate with acrylic super glue. An adhesion test was performed at a cross-head speed of 2 mm/min by a universal testing machine (model 5566S, Instron Co., Canton, MA, USA) with a universal joint to ensure axial loading. The adhesive strength of the beads layer was confirmed from the maximum recorded-load. The mean values of the adhesive strength and standard deviation (SD) measured for B53 and B125 beads were 18.5±3.1 and 13.5±2.9 respectively.
For Microstructural and chemical characterizations, the field emission scanning electron microscope (FE-SEM: JSM-7500 FAM, JEOL, Tokyo, Japan) combined with EDS was used for morphological, fractographical and elemental evaluation of the bead-fused zirconia samples at 15kV of accelerating voltage after the gold sputtering. The surface roughness of the samples was determined by 3D laser microscope (VK- 9710K, Keyence, Osaka, Japan) according to ISO 4287. The mean and SD values of Rz for B125 and B53 beads coated zirconia substrates were 104.41±3.33 µm and 25.32±2.46 µm respectively.
|
| 今後の研究の推進方策 |
The sol-gel technique preparation protocol will be followed to prepare 45S5 BG, by mixing the tetraethylorthosilicate (TEOS, Wako, Tokyo, Japan), nitric acid, triethylphosphate (TEP, Wako, Japan), calcium nitrate tetrahydrate (Wako), sodium nitrate (Wako). The rough bead-fused zirconia substrates will be coated by one-time vacuum sol-dipping method under 0.1 bar pressure will be dipped for 60 s and dried at 60°C for 1 hour will be followed by sintering at 1200°C for 1 hour to melt the BG on the surface in a programmable furnace with a heating rate of 10°C/min. The characterizations such as morphology, adhesion test and roughness will be investigated after BG coating
|
