Residual stress evaluation at the micrometer scale: Analysis of thin coatings by FIB milling and digital image correlation

► Ring-core procedure was proposed and validated for residual stress analysis at the micro-scale. ► Complete stress relief was demonstrated when trench depth approaches stub diameter. ► New method minimises artifacts due to FIB milling process, improving accuracy and resolution. ► Proposed technique was validated for the important practical case of thin coatings. ► Method can be generalized, e.g. to include stress depth profiling and non-equibiaxial stress.