title: Effect of welding parameters on penetration of Nd:YAG laser into cast Ti and Au- and Ag-based alloys.
abstract: OBJECTIVE
  The objective of this study was to investigate the effect of laser welding parameters (current [A], spot diameter [mm], and pulse duration [ms]) on the weld penetration depth by Nd:YAG laser into cast titanium and Ag-based and Au-based alloys.
  
  
  METHODS
  Two cast blocks of each metal were laser welded with various parameters at their interface. The blocks were then separated, and the penetration depth into each metal was measured on the separated surface using a computer program. The data were statistically analyzed.
  
  
  RESULTS
  Increasing the current and decreasing the spot diameter increased the penetration depth into each alloy. No statistical differences in penetration depth were found for each metal among the pulse durations.
  
  
  CONCLUSIONS
  The results suggested that, regardless of the pulse duration, the current and the spot diameter in relation to the power density (W/cm2) of the laser affected the weld penetration depth into each metal. Cast titanium produced more penetration depth compared to gold alloys because of its low thermal conductivity value and high rate of laser beam absorption.
authors.affiliation: Department of Biomaterials Science, Baylor College of Dentistry, Texas A&M University System Health Science Center, Dallas, Texas 75246, USA. iwatanabe@bcd.tamhsc.edu
authors.forename: Ikuya
authors.initials: I
authors.lastname: Watanabe
authors.forename: Naoki
authors.initials: N
authors.lastname: Baba
mesh_terms: D003722:Dental Alloys / Q000528:radiation effects*; D012994:Dental Soldering / Q000379:methods*; D006046:Gold / Q000528:radiation effects; D007834:Lasers; D012834:Silver / Q000528:radiation effects; D014025:Titanium / Q000528:radiation effects*
chemical_list: D003722:Dental Alloys; D012834:Silver; D006046:Gold; D014025:Titanium