Resonant Inspection Applied to 100% Testing of Nodularity of Cast Ductile Iron

Worldwide emphasis on defect-free manufacturing within the automotive sector has driven manufacturers to seek out cost effective methods of 100% inspection. To achieve zero defect output cost-effectively, manufacturers are making the commitment to move to online, automated nondestructive testing (NDT) methods. This type of online inspection requires accuracy, reliability, and high throughput. The Resonant Acoustic Method of Nondestructive Testing (RAM-NDT) is emerging as a type of resonant inspection that is a very efficient method of structural defect discrimination lending itself well to automated online implementation. This paper presents the fundamental principles of the resonant acoustic method and how it is been applied to testing nodularity in ductile iron brake calipers, rotors and anchors.