HTML Assists in Valve Spring Study User Project withD. Holden of Richard Childress Racing
	An engineer from Richard Childress Racing visited the RSUC to investigate why one batch of valve springs lasted and incredible 700+ laps while other batches,  same way, seemingly processed the failed in under 30 laps. We found significant residual stresses in the “good” and “bad” springs in preliminary XRD measurements. More importantly, after electropolishing, we also discovered circumferential surface features, which looked like cracks, in the initial rod stock prior to spring formation. After metallographic imaging, we conducted a simple bending experiment in which these surface features opened into cracks, similar to the scales opening on a bent fish. This was dramatically shown by an impromptu  SEM  session.                                                             D. Holden, the Richard Childress engineer sent the SEM and metallographic micrographs to the alloy manufacturer, which recognized that it had a problem (below). The engineer strongly encouraged the alloy manufacturer to contact the HTML to improve its alloy processing.        Optical micrograph (below) showing the crack–like features. Post-bending the SEM micrograph (right) shows a crack.
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