Abstract
Mechanical properties of commercially pure titanium wires more than 99.4% Ti (KS 70) were tested and the results obtained were compared with those of commercially superior pure titanium wires more than 99.5% Ti (KS 50) previouly reported.
The tensile strength and elongation of KS 70 wire were higher than those of KS 50 wire (Fig. 2) . Repeated bending value of KS 70 wire, however, was inferior to that of KS 50 wire (Fig. 6) . Modulus of rigidity and torsion value were little affected by impurities (Fig. 3 and 4) . KS 70 wire was harder than KS 50 wire and was harden remarkably by cold drawing, and surface hardness was higher than center (Fig 7) . From these considerations, the higher purity titanium seems to be suitable for clasp wire.
