title: Mechanical strength and microstructure of laser-welded Ti-6Al-7Nb alloy castings.
abstract: Mechanical properties of laser-welded castings of Ti-6Al-7Nb alloy, CP Ti, and Co-Cr alloy were investigated and compared to the unwelded castings using a tensile test. Dumbbell-shaped specimens were cut at the center, and two halves of the specimens were welded with an Nd:YAG laser welding machine at 220 or 260 V of laser voltage. The mechanical strength of 260 V groups was higher than that of 220 V groups for Ti-6Al-7Nb and Co-Cr alloys except for CP Ti. All 260 V laser-welded castings of Ti-6Al-7Nb alloy and CP Ti, which fractured outside the welded joints, exhibited ductile characteristics, while all laser-welded Co-Cr alloy castings, which fractured within the welded joints, showed brittle characteristics. This study proved that the mechanical strength of laser-welded Ti-6Al-7Nb alloy and CP Ti castings was as high as that of unwelded castings, while the mechanical properties of laser-welded alloy joints were influenced by microstructural changes.
authors.affiliation: Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Kanda-Surugadai, Chiyoda-ku, Japan.
authors.forename: Viritpon
authors.initials: V
authors.lastname: Srimaneepong
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yoneyama
authors.forename: Equo
authors.initials: E
authors.lastname: Kobayashi
authors.forename: Hisashi
authors.initials: H
authors.lastname: Doi
authors.forename: Takao
authors.initials: T
authors.lastname: Hanawa
mesh_terms: D002858:Chromium Alloys; D003722:Dental Alloys; D003735:Dental Casting Technique; D012994:Dental Soldering; D003799:Dental Stress Analysis; D004548:Elasticity; D006244:Hardness; D007834:Lasers; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D016062:Porosity; D013718:Tensile Strength; D014025:Titanium; D014896:Welding / Q000379:methods*
chemical_list: D002858:Chromium Alloys; D003722:Dental Alloys; C070282:Ti-6Al-7Nb alloy; D014025:Titanium