Plastic strain analysis of the machined surface region using fine grid etched by photoresist technique

The photoresist technique was used to generate a mesh of fine grid pattern to determine the plastic strain distribution in the subsurface of machined workpieces. For this purpose rectangular grids measuring 20 μm by 20 μm with a line thickness of 5 μm were etched on workpieces of inconel-718 nickel-base superalloy and then machined under plane-strain condition. Subsurface plastic strain distribution was determined from distorted grids after machining using standard analytical methods. Using this technique, it was possible to generate a finer rectangular grid size of 5 μm by 5 μm with a 2-μm line thickness.