Thermal Modelling Of Laser Cutting Process Of Ultra High Strength Steels And Optimum Cutting Parameters Selection

Abstract

Weapon and ammunition technologies are developing. This makes armored vehicles to be faster and more agile. To achieve agility, armored vehicles need to be lighter. Certain ballistic levels can be obtained in lower thickness, lower hull weight, and values with the help of Ultra High Strength steels. These steels are manufactured via quenching and tempering operations. Laser cutting, plasma cutting, waterjet cutting, bending and machining are the most common ways of manufacturing with ultra high strength steels. During thermal cutting operations, the cutting area reaches to melting temperature. Inside of the heat affected zone it is expected to see rapidly cooling regions. In the scope of this study laser cutting process is modelled via a volumetric cylindrical heat source. Simulations are repeated for 1900W, 1500W and 1200 W laser power values and 1950 [mm/min], 1200 [mm/min] and 800 [mm/min] feed rates. Results are experimentally validated. Temperature distribution and cooling behavior are investigated via continuous cooling transformation diagrams of Protection 600T steel. As a result, 1200 W and 1200 [mm/min] coupling is selected as the optimum cutting parameter.