Research on an ultrasonic NDT system for complex surface parts

Abstract Aimed at internal quality controlling for complex surface parts, an ultrasonic testing system for complex surface parts has been developed using ultrasonic non-destructive testing (NDT) that has the features of strong penetration, good direction, high sensitivity, low cost, and being harmless to people and materials. The technologies of the computer, numerical control (NC), precision mechanisms, signal analysis and processing were integrated in the testing system. The system includes a PC, a system software, an ultrasonic data acquisition card, a stepper motor drive card and a five-axis precision mechanical device, etc. The software was developed using Windows 98-based VC++. According to CAD data of the parts and interpolation methods, the scanning programs can be programmed. The five-axis scanning system is driven by the CNC (computer numerical control) system to control the attitude of ultrasonic probes. The system’s automatic scanning for complex surface parts, the real-time acquisition of ultrasonic data, and automatic identification of flaw signal have been realized. This system can be used not only for testing complex surface parts, but also, for the random testing of curved parts. With a fast testing speed, high sensitivity, high testing precision and high reliability, the system has wide adaptability.