MEASUREMENTS OF INERTIAL ACOUSTIC CAVITATION EMISSIONS AND THEIR CORRELATION WITH EROSION RESISTANCE OF STAINLESS STEEL 304

I. Ibanez, M. Hodnett, B. Zeqiri, M. N. Frota

Abstract

This work describes a ASTM G32-10 compliant technique for measuring ultrasonic cavitation used to induce erosion in engineering materials. The hydrodynamic cavitation erosion resistance of coupons of stainless steel 304 was investigated by exposure of the material to acoustic cavitation generated by an ultrasound transducer. A 65 mm diameter variant of a cavitation sensor developed by the National Metrology Institute of the UK (NPL) proved to detect broadband acoustic emissions and logs acoustic signals produced in the MHz frequency range. The readings of cavitation were made during the exposure duration at discrete intervals (900 to 7200 s) enabling periodic mass measurements (evaluation of erosion) under a strict protocol. Cavitation measurements were carried out for different positions of the ultrasound transducer horn confronting the material exposed to erosion. For a transducer displacement amplitude of 43.5 µm, maximum variation in measurements of cavitation level was found to be between 2.6% and 3.8% when the separation (λ) between the transducer horn and the specimen amplified from 0.5 to 1.0 mm, respectively. Mass loss of the specimen —a measure of erosion— was 7.5 mg (λ = 0.5 mm) and 6.8 mg (λ = 1.0 mm) for experiments carried out at the same transducer displacement amplitude.

Keywords

metrology, cavitation erosion, ultrasound, CaviMeter, stainless steel 304, standard ASTM G32-10

Download

IMEKO-WC-2015-TC15-322.pdf

DOI

-

IMEKO TC

TC15 - Experimental Mechanics

Back to the proceedings