Engineering Residual Stress Measurement - Isis Project No 1082

An Oxford inventor has demonstrated the principle for a new portable instrument for the measurement of residual stress in engineering components and structures.

The Technology

Every manufacturing process, from casting and forging, to machining and finishing, induces residual stresses in components. For critical components, such as aircraft wings and turbine blades, these stresses affect the durability and lifetime of the structures and assemblies. Current methods are either destructive (e.g. hole drilling), limited to the surface (labratory X-ray), or rely on large facilities (synchrotron and neutron sources). The new method uses a laboratory source of high energy polychromatic X-ray in transmission to evaluate stresses in the bulk of the sample. The method is portable and can be adapted to any number of demanding applications.

Figure 1: Photograph of the X-ray system	Figure 2: Measurement results for a 12mm 12mm bent aluminium alloy bar

The Oxford Invention

• A truly non-destructive method for bulk stress measurement
• Transmission measurement capability using high energy beam
• Penetration depth of 25mm in Aluminium, >5mm in steel and nickel
• High X-ray photon flux
• Portable
• Suitable for large and assembled components
• Cost effective

Commercial Opportunity & Patent Status

This work is patent application protected. Isis wishes to talk to companies interested in developing the commercial opportunities for this technology. Please contact Isis to discuss this further.

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