Detection of Inclusion in molten metal by focused ultrasonic wave

An attempt for detecting impurity particles suspended in molten zinc at 650 degrees C has been made using a focused ultrasonic pulse-echo technique wi th a clad metallic buffer rod. The focused ultrasonic waves are generated b y a spherical acoustic lens which is fabricated at the end of the buffer ro d. An experiment is carried out at 10 MHz. The result shows that impurity p articles in molten zinc are detectable by using the presented focusing buff er rod.