Acoustic studies of some non-transforming and transforming special steels at low temperatures

Abstract

The present investigation on some special steels and on Swedish charcoal iron was undertaken at the request of Sir Robert Hadfield, following my published note describing a simple acoustic method of studying the presistence of vibration of transversely vibrating metals bars at different temperatures. In the present work the vibration frequencies have also been determined. The r wo series of observations give information regarding the internal damping and Young's elastic modulus respectively. Secular as well as temperature changes have been recorded in transforming nickel steels. The experiments have been made between -183ºC and room temperature, and the results, whenever possible, compared with the Hadfield, Dewar-Hadfield, and De Hass-Hadfield low temperature researches on the maximum stress, elongation, yield point, reduction of area, and Brinell hardness of some of the same steels ( see Table III). A list of the materials investigated is given in Table I, together with the data supplied by Sir Robert Hadfield regarding their composition, treatment, Brinell hardness, and specfic magnetism.