CO₂ laser cutting of TiN coated Ti-6A1-4V alloy: Corrosion properties

The rapid growth in the use of high power lasers for profiling sheet materials has generated a great deal of scientific and commercial interest in the quality of the cut edges produced. Consequently, investigation into oxide and corrosion properties of the cut edges may be fruitful in the sheet metal industry. In the present study, CO₂ laser cutting of TiN coated and uncoated Ti-6Al-4V workpieces are carried out. The electrochemical tests are conducted to measure the corrosion resistance of the cut edges. The micro Nuclear Reaction Analysis (μ-NRA) is introduced to determine the oxygen content in the laser cut edge vicinity. SEM is carried out to investigate the metallurgical changes in the heat-affected zone. It is found that the corrosion resistance of the laser melted surfaces improves considerably and oxygen content in cut edge decays rapidly as the distance from the cut edge increases towards the solid bulk.