| Project/Area Number |
04404075
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
補綴理工系歯学
|
|---|
| Research Institution | THE UNIVERSITY OF TOKUSHIMA |
|---|
Principal Investigator |
ASAOKA Kenzo (1993) THE UNIVERSITY OF TOKUSHIMA, SCHOOL OF DENTISTRY, DEPARTMENT OF DENTAL ENGINEERING : PROFESSOR, 歯学部, 教授 (50014189)
桑山 則彦 (1992) 徳島大学, 歯学部, 教授 (60013827)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KAWANO Fumiaki THE UNIVERSITY OF TOKUSHIMA, UNIVERSITY DENTAL HOSPITAL, DEPARTMENT OF REMOVABLE, 歯学部・附属病院, 講師 (60195120)
KON Masayuki THE UNIVERSITY OF TOKUSHIMA, SCHOOL OF DENTISTRY, DEPARTMENT OF DENTAL ENGINEERI, 歯学部, 助手 (80116813)
浅岡 憲三 徳島大学, 歯学部, 助教授 (50014189)
|
|---|
| Project Period (FY) |
1992 – 1993
|
| Project Status |
Completed (Fiscal Year 1993)
|
| Budget Amount *help |
¥23,000,000 (Direct Cost: ¥23,000,000)
Fiscal Year 1993: ¥3,000,000 (Direct Cost: ¥3,000,000)
Fiscal Year 1992: ¥20,000,000 (Direct Cost: ¥20,000,000)
|
|---|
| Keywords | Material processing / Simulation / Dental porcelains / Dental casting alloys / Phase transformation / Stress analysis / Thermal diffusivity / Porcelain-fused-to-metal restorations / 熱伝導率 / 金属焼付陶材 |
|---|
| Research Abstract |
Simulation on material processing was carried out as the following :
1. Measurements of thermo-physical properties of the substrates : especially, relationship between phase transformation and change of physio-mechanical properties. 2. Studies on the relationships between process conditions and rate of phase transformation and/or temperature and stress distributions. 3. Programming of the process simulation. 4. Verification of the computer simulation program. 5. Validation of the simulated results by experimental technique.
Phase 1 : Temperature dependence of the viscosity, specific heat, thermal diffusivity and thermal conductivity was measured from room temperature to the glass transition temperature (30-700ﾟC) for the commercial dental porcelains. For the Au-based, Au-Pd based, Ag-based and Ni-based dental alloys for ceramics, temperature dependence of coefficient of thermal expansion, specific heat, thermal diffusivity and thermal conductivity was measured. Especially, relationships
… More
between phase transformation and change of volume were clarified. Phase 2 : Temperature distribution in the material was measured during tempering of the porcelain, related to the thickness of the porcelain slab. Phases 3 and 4 : Procedure of the process simulation was developed and showed the results of demonstrated examples. Relationships between the geometrical shapes of laminated substrates and residual stress in the system were discussed. Phase 5 : Acoustic emission was measured during heating/cooling of the tempered porcelain and porcelain-metal strips. The results showed that elastic energy is dispersed related to the viscous flow of the porcelain at the glass transition temperature. These experimental results had good agreements with the simulations. Residual stress was evaluated for the tempered porcelains by the indentation micro-fracture method. The stress levels which were experimentally measured, were consisted with the process simulation.
Process simulation on the dental casting was also studied ; that is, thermo-physical properties for the materials related to the casting were measured. Less
|
