title: Enhanced surface hardness by boron implantation in Nitinol alloy.
abstract: Boron implantation into Nitinol alloy has a potential for developing improved Nitinol root canal instruments with excellent cutting properties, without affecting their superelastic bulk-mechanical properties. The surface hardness of nickel-titanium (NiTi) alloy, also known as "Nitinol" (50 atm% nickel+50 atm% titanium), has been improved by ion-beam surface modification. With an implantation dose of 4.8 x 10(17) boron/cm2, a high concentration of boron (30 atm%) is incorporated into NiTi alloy by 110 keV boron ions at room temperature (25 degrees C). Boron-implanted and unimplanted (pure) Nitinol alloys show surface hardness of 7.6 +/- 0.2 and 3.2 +/- 0.2 GPa, respectively, at the nanoindentation depth of 0.05 micron. The ion-beam-modified NiTi alloy exceeds the surface hardness of stainless steel.
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta 30332-0245, USA.
authors.forename: D H
authors.initials: DH
authors.lastname: Lee
authors.forename: B
authors.initials: B
authors.lastname: Park
authors.forename: A
authors.initials: A
authors.lastname: Saxena
authors.forename: T P
authors.initials: TP
authors.lastname: Serene
mesh_terms: D001895:Boron / Q000737:chemistry; D003722:Dental Alloys / Q000737:chemistry*; D003762:Dental Instruments; D004526:Efficiency; D004867:Equipment Design; D006244:Hardness; D006245:Hardness Tests; D008422:Materials Testing; D009532:Nickel / Q000737:chemistry*; D018915:Root Canal Preparation / Q000295:instrumentation*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D003722:Dental Alloys; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium; D001895:Boron