Residual stress engineering
Residual stresses have an important role in failure of components by fatigue, fracture, and corrosion, and can be especially effective in slowing and arresting crack growth driven by fatigue or stress corrosion. Conventional residual stress treatments, including shot peening and cold-hole expansion, are useful tools for improving the capability of components in industries like aviation, ground vehicle, and power generation. Newly developed residual stress treatments have been applied to aircraft engine components, enhancing damage tolerance, service life, and readiness. However, both conventional and new residual stress treatments have been deployed without consistent and proven engineering approaches, instead developing through a point-design approach that has relied on extensive trial-and-error and expensive full-scale testing. This has resulted in residual stress treatment solutions taking years to reach the field, and data generated not being used to support follow-on residual stress treatment applications. New engineering tools are needed to engage these treatments in cost-effective solutions to the full range of fatigue and corrosion problems met in operational systems.
Hill Engineering has developed a set of integrated tools for residual stress engineering that enables rapid assessment of residual stress treatment value by manufacturers and maintainers of metallic components and systems. The tools include detailed engineering methods to simulate residual stress treatments, predict residual stress and fatigue life, measure residual stress fields, and capture and reuse historical residual stress engineering data. These tools provide rapid evaluation and validation of residual stress treatments and enable benefits such as those achieved historically in engine blades by laser shock peening (resulting in increased time-on-wing and reduced unscheduled engine removals).
We are actively working with manufacturers, operators, and government agencies to further develop and deploy these capabilities for improvements in new and existing components and systems, particularly in the aviation market for use in engines, airframes, and landing gear.