In this work laser surface nitriding was performed to enhance wear and erosion resistance of pure
titanium by increasing its surface hardness while keeping the strength and ductility of the core for static
and dynamic loading resistance. The Response Surface Methodology (RSM) in the Design of Experiment
(DOE) statistical method is adopted in this research work to perform the experimental design, analysis
and optimization of the laser nitriding process. Continuous wave CO2 laser was used to melt the surface,
and then nitrogen gas was incorporated into the melted pool to produce hard TiN. The Response Surface
Design was first created using MINTAB program, and then the laser nitriding process was performed
according to the planned design. Microhardness is then measured for each sample, which represents
the response, and incorporated into the design matrix. Results are then analyzed and a RSM model
was developed and verified. The model is then used to perform parametric study and optimization.
The maximum measured microhardness based on the original RSM design was 1382 HV0.15. However,
based on the model prediction, the optimal process parameters settings were found to be as: 2.84 kW
laser power, 5 mm/s scanning speed and 2076 l/h nitrogen flow rate which would result in a maximum
microhardness of approximately 1920 HV0.15