Magnetic susceptibility of some materials used for apparatus construction (at 295 K)

Abstract

The magnetic susceptibility, X, at 295 K of a wide variety of common laboratory construction materials has been carefully measured. Only materials with well-characterized compositions are included in the final data. Materials such as eu alloys and fined epoxies showing ferromagneticlike saturation behavior are listed with the recognition that workers will probably want to use these with great caution in precision experiments where magnetic effects may be a source of error. Susceptibility values are given for over 30 materials for which X values are not available in the literature and which exhibit X independent of H.

Magnetic properties of materials for MR engineering, micro-MR and beyond

“…To compare the values, we added the literature value of the susceptibility of water at 20 • C, -9.032 ppm [1], to our results, assuming that the uncertainty of that value is negligible compared to our accuracy. The the comparison to [9] in table 7 show a good agreement within the uncertainties of their measurement, except for the value of N-BK7 vs. BK7. We presume that what is referred to as BK7 in [9] is indeed the "old style" BK7 or another glass with the same optical properties from a different manufacturer, not N-BK7, and may thus have a significantly different susceptibility as we also observed in the dense flint glasses.…”

“…The the comparison to [9] in table 7 show a good agreement within the uncertainties of their measurement, except for the value of N-BK7 vs. BK7. We presume that what is referred to as BK7 in [9] is indeed the "old style" BK7 or another glass with the same optical properties from a different manufacturer, not N-BK7, and may thus have a significantly different susceptibility as we also observed in the dense flint glasses.…”

“…The method of [9] was based on a force measurement of the sample in a magnetic field, so there may be no common methodological problems affecting both measurements in the same way. To compare the values, we added the literature value of the susceptibility of water at 20 • C, -9.032 ppm [1], to our results, assuming that the uncertainty of that value is negligible compared to our accuracy.…”

“…Beyond this, there are various measurements of smaller sets of sample materials obtained with different methods [9,2,3,7,10,11]. Hence, we believe that a database of magnetic susceptibility values for commonly used materials in MR engineering and micro-MR, obtained in a consistent manner, would be a useful tool in the field.…”

“…Hence, we believe that a database of magnetic susceptibility values for commonly used materials in MR engineering and micro-MR, obtained in a consistent manner, would be a useful tool in the field. Additional values can be found in particular for metals in [2] for polymers in [2,9] and for fluids in [3,7], albeit usually at a lower accuracy.…”