The Contour Method relies on the principles of solid mechanics and involves dividing a specimen into two parts and measuring the deformation caused by the redistribution of residual stress to determine the residual stress. This technique is usually conducted on metallic components that can be sliced with an Electric Discharge Machine (EDM).

Advantages:

The Contour Method has several advantages, such as being able to measure depth as much as the wire EDM and CMM axis ranges allow, producing a full field 2D stress map, and maintaining accuracy even when cut depth is increased. It is also a simple process that uses readily available hardware and software and is cost-effective for the amount of stress data produced. Additionally, it is not affected by the grain structure or texture of the component material, and its clean EDM surface enables further research.

Disadvantages:

However, the technique has some downsides, such as being destructive, requiring laboratory-based measurements, only allowing uni-axial residual stress measurements, and being challenging to apply to complex shaped components. Moreover, it is least accurate at specimen surfaces, and its accuracy depends on reliable contour measurement data, which can be affected by smoothing and filtering.