1924 Trade Marks Jrnl. 3 Sept. 2000 Magnaflux... Rolled steel bars.]

1935 Engineer 8 Mar. 249/1 The ‘Magna-Flux’ method..reveals cracks by the concentration of iron particles under the influence of a magnetic field.

1938 S.A.E. Jrnl. May 36/1 Another method of magnetic testing..involves the use of Magnaflux in which the parts to be inspected are first longitudinally or circularly magnetized... When properly magnetized, defects result in local flux leakage. Magnaflux powder, being of high magnetic permeability..adheres along the lines of flux leakage.

1940 J. I. Crump & N. Maul Our Airliners vii. 139 Every piece is measured and checked for wear and many of the parts go to the magnaflux tank.

1963 F. D. Jones & P. B. Schubert Engin. Encycl. (ed. 3) 783 Although the Magnaflux method of inspection has been universally adopted throughout the aircraft industry it is by no means confined to it.

1980 R. D. Bent & J. L. McKinley Aircraft Maintenance & Repair (ed. 4) vii. 199/2 Magnetic-particle inspection (Magnaflux)..is an efficient, practical, and non-destructive method that will reveal the presence of tiny cracks..in a welded part.

1959 Manch. Guardian 3 Jan. 5/4 ‘Magnaflux the elephant ears and run a test on the kill switch before checking out the tranquillisers.’ This is not a code. A technician at the new American air base at Vandenberg, California, would understand it perfectly.

1987 Dirt Wheels Mag. Aug. 25/1 You can take the stock rod and have it magnafluxed for hidden flaws and then shot-peened for strength.