Hematite grains: Size and coercive force from AF demagnetization at high temperatures |
| |
Authors: | Mohamad Mansour Bina Michel Prévot |
| |
Affiliation: | 1. Department of Physics, Science Faculty, University of Tehran, Tehran, Iran;2. Laboratoire de Géomagnétisme, Université Paris VI, 94100 St.Maur-des-Fossés, France |
| |
Abstract: | The coercivity spectrum of low-field high-temperature partial thermoremanent magnetization (PTRM) of a synthetic hematite powder, extremely high at room temperature, decreases very slowly with increasing temperature up to 500°C then decreases rapidly, especially above 600°C. From the AF demagnetization curves at 600 and 650°C it is calculated, following the Néel's theory of single-domain particles that the grains carrying the PTRM have a mean coercive force of 23 ± 5 kOe and a mean grain size of 0.40 ± 0.15 μm, which is not significantly different from the mean grain size of 0.48 ± 0.03 μm from electron micrograph observations. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|