Metallurgical effects on titanium by laser welding on dental stone.
It is not known for certain that dental stone components influence titanium welding. In this study, we investigated metallurgical problems caused by laser welding on dental stones using wrought commercial pure (CP) titanium. A pulsed Nd:YAG laser irradiated a number of specimens' surfaces which were fixed on either a dental hard stone or a titanium plate. The metallurgical properties of the weld were evaluated using the Vickers hardness test, microstructure observation, fractured surface observation and quantitative analysis of oxygen and hydrogen. In the weld formed on the dental stone there was an increase in hardness, the existence of an acicular structure and a brittle fractured surface, and an increase in the oxygen and hydrogen concentrations compared with base metal. In the weld formed on the titanium plate, these changes were not observed. Therefore, it was demonstrated that laser welding on dental stones made the welds brittle.
Graduate School of Dentistry (Geriatric Dentistry), Osaka Dental University, 8-1 Kuzuhahanazono-cho, Hirakata-shi, Osaka 573-1121, Japan.
Sonosuke
S
Fujioka
Kazutoshi
K
Kakimoto
Taro
T
Inoue
Joji
J
Okazaki
Yutaka
Y
Komasa
D000704:Analysis of Variance; D002133:Calcium Sulfate / Q000528:radiation effects; D012994:Dental Soldering / Q000379:methods*; D004307:Dose-Response Relationship, Radiation; D006244:Hardness; D006859:Hydrogen / Q000032:analysis; D007834:Lasers; D008422:Materials Testing; D008669:Metallurgy; D008855:Microscopy, Electron, Scanning; D003765:Models, Dental; D015394:Molecular Structure; D009354:Neodymium; D010100:Oxygen / Q000032:analysis; D016062:Porosity; D013499:Surface Properties / Q000528:radiation effects; D014025:Titanium / Q000737:chemistry*; D014896:Welding / Q000379:methods
D009354:Neodymium; D006859:Hydrogen; D014025:Titanium; D010100:Oxygen; D002133:Calcium Sulfate