各種接着試験法における接着界面の破面解析および応力解析

抄録

To clarify the differences in fracture mechanism when different modes of load were applied, two types of dental adhesives were used in various tests-for tensilestrength, compressive shear strength, flexural strength and cleavage strength-and fractographical analyses of the bonding surface after breakage were perfomed by SEM. Furthermore, the distribution of stress in the adhesive layer subjected to tensile, compressive shear and torsion loads was examined by three-dimensionalphotoelastic analysis. The results were as follows:
1. The kind of fracture occurring in two types of adhesive was cohesive fracture due to a force induced in the adhesive layer.
2. Fractographical analysis of Panavia EX by SEM revealed the occurrence of a brittle fracture characterized by a river-like pattern inall but one of the tests for tensile strength.
3. Super Bond C & B presented a ductile fracture featuring elongated dimples in tests for tensile strength, 4-point flexural strength, and compressive shear strength. In cleavage strength and 3-point flexural strength test, the ductile fracture had tear dimples.
4. The compressive shear strength test revealed that the amount of stress was the smallest in the central area of the bonding surface and tended to increase toward the upper and lower margins.
5. In the torsion test, stress gradually increased from the center outward.