title: Grindability of alpha-case formed on cast titanium.
abstract: The hardened alpha-case (alpha-case) layer inevitably forms on the surface of titanium castings when prepared by investment casting. Because the hardness of the alpha-case is incomparable to that of the interior structure, the perception exists that the alpha-case is difficult to remove during cutting, grinding and polishing. Grindability (ease of grinding) of cast cpTi and cast Ti-6Al-4V was evaluated by grinding cast specimens incrementally using a SiC abrasive wheel. The present study revealed that the presence of the brittle alpha-case with lower fracture toughness is beneficial in grinding titanium. The alpha-case on the ductile cpTi can be ground much easier than its bulk interior structure. In less ductile Ti-6Al-4V, the grinding rate is much higher than that of cpTi, and the alpha-case and its interior structure are at similar levels since the fracture toughness of its alpha-case and the bulk material is not large enough.
authors.affiliation: Texas A&M Health Science Center, Baylor College of Dentistry, Department of Biomaterials Science, Dallas TX 75246, USA. mkoike@bcd.tamhsc.edu
authors.forename: Marie
authors.initials: M
authors.lastname: Koike
authors.forename: David
authors.initials: D
authors.lastname: Jacobson
authors.forename: Kwai S
authors.initials: KS
authors.lastname: Chan
authors.forename: Toru
authors.initials: T
authors.lastname: Okabe
mesh_terms: D000497:Alloys; D000704:Analysis of Variance; D003722:Dental Alloys; D003735:Dental Casting Technique; D003764:Dental Materials; D003775:Dental Polishing / Q000379:methods*; D017267:Dental Prosthesis Design / Q000379:methods*; D004583:Electrons; D008669:Metallurgy / Q000379:methods; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium
chemical_list: D000497:Alloys; D003722:Dental Alloys; D003764:Dental Materials; C031462:titanium alloy (TiAl6V4); D014025:Titanium