The cracks are really showing at MIRA

Automotive development experts MIRA have launched a new service that enables highly accurate measurements of how microscopic cracks propagate through materials, leading to better designs that last longer.

The accurate measurement of crack growth equips design engineers with the vital materials data necessary to model new parts in specialised FEA codes incorporating the latest crack growth predictive capabilities …data that until now has been widely unavailable. It also enables engineers to make powerful prognoses on the lifespan of existing equipment.

MIRA’s latest fatigue testing system goes beyond traditional stress/strain fatigue studies to include the kind of crack growth analysis currently the reserve of a handful of blue chip aerospace companies. Housed inside a specialised climatic chamber, testing is sustained at temperatures between -150 and +350 Deg C. The new equipment represents an investment in excess of £100,000.

Materials Manager Andi Clements enthused: “We’re capable of measuring crack growth down in the angstrom range …our incredibly fine resolution allows us to plot growth at low energy levels far more accurately than anyone in the automotive sector will have seen before.”

Fracture growth data has been noticeably absent from the automotive engineering ‘toolbox’, despite the aerospace community employing similar techniques for some time. MIRA have successfully transferred this vital enabling technology from their work in the aerospace sector, reapplying it in a unique and award winning way.

David Ensor, MIRA’s Senior Durability Consultant explains further: “These essential fracture mechanics material properties provide one of the most difficult-to-obtain inputs for fatigue engineers. We can now predict the total life of vehicle systems and components. MIRA’s overall integrated durability engineering strategy combines road-load-data measurements taken from either the virtual or real proving ground or the public road, with the design geometry and these complete material properties (fracture & crack initiation) to provide design level total life …rather than waiting for the completion of lengthy proving tests.”