IN-PROCESS MONITORING OF SURFACE-ROUGHNESS UTILIZING ULTRASOUND

This paper presents the capability of an ultrasonic system for the in- process surface roughness measurement of machined parts. The system us es a focused ultrasonic transducer to measure the reflected amplitude variation of art ultrasonic beam incident on the surface. The robustne ss of the system is examined by applying the technique to different ma chined surfaces and investigating the effect of various coupling fluid s. Experimental results show that the technique is applicable to the s urfaces produced by most production processes. In addition, the capabi lity of in-process measurements is demonstrated by adapting the system to a CNC machining center. Results show in-process measurements corre late well with off-line profilometer data. Tolerance to machine vibrat ion is also shown by comparing the measurement data with the machine s pindle on and off.