title: Mechanical properties of cast Ti-Hf alloys.
abstract: This study examined the mechanical properties of a series of Ti-Hf alloys. Titanium alloys with 10 to 40 mass % Hf were made with titanium and hafnium sponge in an argon-arc melting furnace. Specimens cast into magnesia-based investment molds were tested for yield strength, tensile strength, percentage elongation, and modulus of elasticity. Vickers microhardness was determined at 25 to 600 microm from the cast surface. X-ray diffractometry was also performed. Commercially pure Ti (CP Ti) and pure Ti prepared from titanium sponge were used as controls. The data (n = 5) were analyzed with a one-way ANOVA and the Student-Newman-Keuls test (alpha = 0.05). The diffraction peaks of all the metals matched those for alpha Ti; no beta phase peaks were found. Alloys with Hf > or = 25% had significantly (p < 0.05) higher yield and tensile strength compared to the CP Ti and pure Ti. There were no significant differences (p > 0.05) in elongation among all the Ti-Hf alloys and CP Ti, whereas the elongation of alloys with Hf > or = 30% was significantly (p < 0.05) lower than that of the pure Ti. The cast Ti-Hf alloys tested can be considered viable alternatives to CP Ti because they were stronger than CP Ti and had similar elongation.
authors.affiliation: Division of Operative Dentistry, Graduate School of Dentistry, Tohoku University, 4-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan. yamasa@wf7.so-net.ne.jp
authors.forename: Hideki
authors.initials: H
authors.lastname: Sato
authors.forename: Masafumi
authors.initials: M
authors.lastname: Kikuchi
authors.forename: Masashi
authors.initials: M
authors.lastname: Komatsu
authors.forename: Osamu
authors.initials: O
authors.lastname: Okuno
authors.forename: Toru
authors.initials: T
authors.lastname: Okabe
mesh_terms: D000497:Alloys / Q000138:chemical synthesis* / Q000737:chemistry / Q000592:standards*; D001672:Biocompatible Materials / Q000737:chemistry* / Q000592:standards; D004548:Elasticity; D006195:Hafnium; D008422:Materials Testing; D019563:Mechanics; D013718:Tensile Strength; D014025:Titanium; D014961:X-Ray Diffraction
chemical_list: D000497:Alloys; D001672:Biocompatible Materials; D014025:Titanium; D006195:Hafnium