Parametrical optimization of laser surface alloyed NiTi shape memory alloy with Co and Nb by the Taguchi method

K. W. Ng, H. C. Man, J. Lawrence, T. M. Yue

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)


Different high-purity metal powders were successfully alloyed on to a nickel titanium (NiTi) shape memory alloy (SMA) with a 3kW carbon dioxide (CO2) laser system. In order to produce an alloyed layer with complete penetration and acceptable composition profile, the Taguchi approach was used as a statistical technique for optimizing selected laser processing parameters. A systematic study of laser power, scanning velocity, and pre-paste powder thickness was conducted. The signal-to-noise ratios (S/N) for each control factor were calculated in order to assess the deviation from the average response. Analysis of variance (ANOVA) was carried out to understand the significance of process variables affecting the process effects. The Taguchi method was able to determine the laser process parameters for the laser surface alloying technique with high statistical accuracy and yield a laser surface alloying technique capable of achieving a desirable dilution ratio. Energy dispersive spectrometry consistently showed that the per cent by weight of Ni was reduced by 45 per cent as compared with untreated NiTi SMA when the Taguchi-determined laser processing parameters were employed, thus verifying the laser's processing parameters as optimum.

Original languageEnglish
Pages (from-to)969-979
Number of pages11
JournalProceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture
Issue number8
Early online date24 Apr 2009
Publication statusPublished - 1 Aug 2009
Externally publishedYes


  • Laser surface alloying
  • NiTi
  • Taguchi method

ASJC Scopus subject areas

  • Mechanical Engineering
  • Industrial and Manufacturing Engineering


Dive into the research topics of 'Parametrical optimization of laser surface alloyed NiTi shape memory alloy with Co and Nb by the Taguchi method'. Together they form a unique fingerprint.

Cite this