title: Grindability of cast Ti-6Al-4V alloyed with copper.
abstract: OBJECTIVE
  This study investigated the grindability of cast Ti-6Al-4V alloyed with copper.
  
  
  METHODS
  The metals tested were commercially pure titanium (CP Ti), Ti-6Al-4V, experimental Ti-6Al-4V-Cu (1, 4, and 10 wt% Cu), and Co-Cr alloy. Each metal was cast into five blocks (3.0 x 8.0 x 30.0 mm(3)). The 3.0-mm wide surface of each block was ground using a hand-piece engine with an SiC wheel at four circumferential speeds (500, 750, 1000, and 1250 m/min) at a grinding force of 100 g. The grindability index (G-index) was determined as volume loss (mm(3)) calculated from the weight loss after 1 minute of grinding and the density of each metal. The ratio of the metal volume loss and the wheel volume loss was also calculated (G-ratio, %). Data (n = 5) were statistically analyzed using ANOVA (alpha= 0.05).
  
  
  RESULTS
  Ti-6Al-4V and the experimental Ti-6Al-4V-Cu alloys exhibited significantly (p < 0.05) higher G-indexes compared with CP Ti and Co-Cr at any rotational speed except for the lowest speed (500 m/min). At 500 m/min, the G-index of Ti-6Al-4V-Cu increased as the amount of alloyed copper increased. The 4% Cu and 10% Cu alloys had significantly greater G-indexes than did 1% Cu and Ti-6Al-4V at the highest rotational speed (1250 m/min). Increasing the percentage of alloyed copper and the circumferential speed also increased the G-ratio.
  
  
  CONCLUSIONS
  A slight reduction in ductility due to alloying Ti-6Al-4V with copper improved the grindability of some of the resultant Ti-6Al-4V-Cu alloys.
authors.affiliation: Department of Biomaterials Science, Baylor College of Dentistry, Texas A&M University System Health Science Center, Dallas, TX 75246, USA. iwatanabe@bcd.tamhsc.edu
authors.forename: Ikuya
authors.initials: I
authors.lastname: Watanabe
authors.forename: Takayuki
authors.initials: T
authors.lastname: Aoki
authors.forename: Toru
authors.initials: T
authors.lastname: Okabe
mesh_terms: D000497:Alloys; D017554:Carbon Compounds, Inorganic / Q000737:chemistry; D002858:Chromium Alloys / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D003722:Dental Alloys / Q000737:chemistry*; D003734:Dental Casting Investment / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry; D003775:Dental Polishing; D006244:Hardness; D006801:Humans; D008422:Materials Testing; D008669:Metallurgy; D017655:Silicon Compounds / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*
chemical_list: D000497:Alloys; D017554:Carbon Compounds, Inorganic; D002858:Chromium Alloys; D003722:Dental Alloys; D003734:Dental Casting Investment; D003764:Dental Materials; D017655:Silicon Compounds; C031462:titanium alloy (TiAl6V4); D003300:Copper; D014025:Titanium; C022088:silicon carbide