National Physical Laboratory

Measuring strain in automotive engines

Investigating the failure of quartz crystal based sensors used for strain measurement on rotating machinery.

The Challenge

SAW pressure device
SAW pressure device

Diced quartz wafers are a critical component of Surface Acoustic Wave (SAW) devices which are used to measure strain on the rotating parts of automotive and marine engines. These devices could potentially find wider industrial application but minute surface defects on the quartz can lead to cracking and eventually fracturing, thus reducing their reliability.

The Solution

A joint research project between NPL, Crane Electronics Ltd, Sensor Technology Ltd and Transense Technologies plc, was undertaken to investigate fracturing and attempt to minimise the risk. It combined NPL's strengths in adhesives and measurement techniques with the specialist SAW expertise of Transense Technologies plc and the torque engineering skills of Sensor Technology Ltd and Crane Electronics Ltd.

The Impact

The project revealed marked differences between vendors in the quality of quartz wafers and dies. As a result, the partners were able to negotiate with suppliers to ensure a much higher degree of quality control.

"NPL's specialist measurement techniques have deepened the understanding of the nature of quartz dies. We are now able to take SAW sensors to much higher strain levels than previously. This is the key to their use in automotive applications."
Dr Ray Lohr, Technical Director, Transense Technologies

Find out more about NPL's research in Advanced Manufacturing and Advanced Materials

Do you have a measurement challenge that you'd like NPL's help with? If so, why not apply for NPL's Technology Innovation Fund ?

Last Updated: 9 Apr 2013
Created: 3 Jun 2010


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