Acoustic Resonance Testing of PM parts with adaptation to the current production lot: Practical Aspects and Novel Software Functions

摘要

Acoustic resonance testing (ART) is a well-established non-destructive testing (NDT) technology for all kinds of sintered parts in mass production, a comparative method for in-line 100% quality assessment of the full volume of a part. The functional principle of the method is explained and how adaptation to the current production lot enhances the sensitivity for defects. As a practical requirement the parts used for adaptation are cross-checked and must be defect-free. An unusual high scatter in the acoustic characteristics of these parts can trigger an alarm regarding constant product quality and decreasing sensitivity for defects. It helps to prevent residual errors slipping through. An unusual low scatter in the acoustic characteristics of adaptation parts can trigger a hint that the production process is under perfect control. It helps to prevent the comparative testing method from sorting out conspicuous parts in a hypercritical way. Software functions help to handle both cases.