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A convenient standard for low-field susceptibility calibration
J Rosenbaum1, E Larson, R Hoblitt
1Department of Geological Sciences, University of Colorado, Boulder, Colorado 80309, USA.
The Review of Scientific Instruments
|August 1, 1979
Summary
Calibration standards using magnetic iron oxide and glass powders offer moderate accuracy for low-field magnetic susceptibility measurements. These versatile powder mixtures are nearly linear with iron oxide concentration.
Area of Science:
- Geophysics and Materials Science
Background:
- Accurate magnetic susceptibility measurements are crucial in various scientific fields.
- Existing calibration standards may have limitations in terms of accuracy, shape, or size.
- Development of convenient and adaptable calibration standards is needed.
Purpose of the Study:
- To develop and characterize a novel calibration standard for low-field magnetic susceptibility measurements.
- To assess the accuracy and linearity of the proposed standard.
Main Methods:
- Preparation of finely ground mixtures of magnetic iron oxide and glass.
- Fabrication of calibration standards in various shapes and sizes using powder mixtures.
- Measurement of magnetic susceptibility for mixtures with varying iron oxide concentrations (0.063% to 11.8% by weight).
Main Results:
- The magnetic iron oxide-glass mixtures provide a calibration standard with moderate accuracy (approx. 5%).
- Susceptibility values ranged from 2.65 x 10(-7) to 5.77 x 10(-5) m3/kg.
- A nearly linear relationship was observed between magnetic susceptibility and iron oxide concentration.
Conclusions:
- Finely ground magnetic iron oxide and glass mixtures are effective calibration standards for low-field magnetic susceptibility.
- The powder form allows for versatile fabrication of standards.
- The linear response simplifies calibration and data interpretation.
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