Background

Machining of difficult-to-machine alloys can often lead to formation of a hardened “white layer” on the work piece surfaces. White layer is a thin layer that can form on the surface of machined metallic components. Components that have white layer are susceptible to early part failure, which in aerospace components can be catastrophic. As such, the presence of this feature is considered a defect and the component would fail surface integrity assessment. Currently the only method of reliably detecting white layers in various metals is destructive. In addition to machining, a white layer could be formed in shaping and forming operations as well as on rail tracks and wheels, due to friction at the rail-wheel interface.

Manufacturers of high value components are very cautious about pushing tools to fullest due to the possibility of white layer formation. By allowing non-destructive inspection on production components tools can be pushed further with the confidence that the resultant surface can still be validated. Inspection of every part can give more insight on tool wear and its effects on the part produced, creating more returns for the industry. As the current testing methods are sacrificial all components produced aren’t subject to testing, highlighting low compliance checking of products which can affect many lives when in service in extreme conditions.

The University of Sheffield’s Advanced Manufacturing Research Centre (AMRC) has developed a non-destructive testing method using X-Ray Diffraction (XRD) technology which offers significant improvements to existing destructive process of white layer and near surface abnormalities detection. The team are working to commercialise this technology, and are keen to speak to anybody from industry who has experience of managing surface defects such as white layer in production components.

Technology Overview

The University of Sheffield’s Advanced Manufacturing Research Centre’s (AMRC’s) Machining Group has developed a novel defect detection system for capturing abnormalities in the near-surface of metallic materials.

The method of detecting the white layer does not need to be disclosed at this stage. However, the current technology development program titanium, nickel and steel alloys applications were researched, and the technique was shown to facilitate white layer detection in each material.

Stage of Development

The technology is currently at Technology Readiness Level (TRL) 3 and working with partners for initial product testing.

Benefits

It is understood that this is the only method of non-destructively testing white layer in all metals, which could have a significant benefit to the industry.

Portability of the method offers the potential for inspecting production parts in minutes instead of days.
Improves confidence in the production quality of the component.
Removes the need for chemical etching for some materials making process eco friendly.
More revenue by removing cruel sacrificial inspection methods on production parts.
Enables faster inspection and component validation with full compliance.

Applications

Aerospace
Rail
High value parts manufacturing

Opportunity

Seeking individuals who are keenly aware of surface defects like white layer, and who would be benefitted by being able to non-destructively test for it
Seeking partners for initial case studies
Available for non-exclusive licensing

Detection of Machining-induced Surface Anomalies using X-ray Diffraction

Patents

IP Status

Seeking