[Mechanical properties and phase transformation of super-elastic Ni-Ti alloy wires. Part 1: Relation between super-elasticity and phase transformation].
The relationship between mechanical properties and thermal behavior of super-elastic Ni-Ti alloy orthodontic wires was investigated in order to use them effectively in clinics. Three types of super-elastic Ni-Ti alloy orthodontic wires, SENTALLOY-BLUE(SB), YELLOW(SY) and RED(SR), were used. Two parameters were introduced from the load-deflection curves in three point bending test to evaluate their mechanical properties. One was the super-elastic index (SEI) for super-elasticity, and the other was the E-load for the load in the super-elastic region. Their thermal behavior in the course of the transformation analyzed with DSC, and compared with the mechanical properties. The specimens heat-treated at 500 degrees C for 30 min were also examined. The differences in mechanical properties of the super-elastic Ni-Ti alloy orthodontic wires used in this study were thought to be more affected by the height of the thermic peak and the form of the DSC curves than the transformation temperature. The higher the thermic peak, the higher tended to be the SEI and the lower E-load. To the contrary, the lower thermic peak, the higher was the E-load and the lower was the SEI, and the continuous force could not be achieved. The remaining work-hardened structure was thought to influence these differences.
Hamanaka
H
H
Yoneyama
T
T
Doi
H
H
Okamoto
Y
Y
Mogi
M
M
Miura
F
F
D003722:Dental Alloys; D003799:Dental Stress Analysis; D004548:Elasticity; D009532:Nickel; D009967:Orthodontic Appliances; D009969:Orthodontic Wires; D013696:Temperature; D014025:Titanium
D003722:Dental Alloys; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium