Peculiarities of radiation damage in ferrites with spinel structure

Abstract

I n ZnFe,O, irradiated by fast neutrons a superparamagnetic state (an ensemble of ferrimagnetic regions with equally probable distribution of cations over Aand B-sites in paramagnetic matrix) is achieved. The properties of superparamagnetic state allow to make conclusions about the character of replacement cascades in ferrites with spinel structure.Some parameters of the replacement cascade are given. It is shown experimentally how the irradiation temperature influence the size of the disordered regions.In ZnFqO,, das mit schnellen Nentronen bestrahlt wurde, wird ein superparamagnetischer Zustand erhalten (ein Ensemble von ferrimagnetischen Bereichen mit einer Wahrscheinlichkeitsgleichverteilung der Kationen iiber die Aund B-Pliitze in einer paramagnetischen Matrix). Die Eigemchaften des superparamagnetischen Zustands erlauben Schliisse iiber den Charakter der Verlagerungskaskaden in Ferriten mit Spinellstruktur. Einige Parameter der Verlagerungskaskade werden angegeben. Es wird experimentell gezeigt, wie die Bestrahlungstemperatur die GroDe der fehlgeordneten Bereiche beeinflul3t.

Electromagnetic material changes for remote detection and monitoring: a feasibility study: Progress report

“…For example, Bi 4 Ge 3 O 12 (BGO) films have shown a linear increase in capacitance after the threshold of ~1.8 mGy was reached [12]. Likewise, many other examples in both ferromagnetic [13] and ferroelectric [14] materials could be given where radiation-induced changes were quasi-permanent until annealed at high temperature.…”

Materials Degradation and Detection (MD2): Deep Dive Final Report

“…Neutron damage studies of magnetic sensor materials are few and far between (see Appendix for an incomplete summary), and results indicate a wide range of behaviors, including amorphization (Chukalkin et al 1983), cation site mixing (Chukalkin et al 1975), superparamagnetism (Parkhomenko et al 1976), anisotropy change (Chukalkin et al 1981), loss of remnance (Anderson et al 2005), or complete loss of magnetization due to radiation-induced thermal spikes (Liu et al 2007). In addition to their use in magnetostrictive transducers, magnetic materials are integral to the operation of linear variable differential transformers (LVDTs), which will also find future use as in-pile diagnostic instruments ).…”