Apparent superparamagnetic behavior of some coarse-grained synthetic titanomagnetite

Details Apparent superparamagnetic behavior of some coarse-grained synthetic titanomagnetite Apparent superparamagnetic behavior of some coarse-grained synthetic titanomagnetite

Jul 1981

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1981pepi...26...27d&link_type=abstract

Physics of the Earth and Planetary Interiors, Volume 26, Issue 1-2, p. 27-36.

Physics

11

Scientific paper

Magnetic hysteresis and initial susceptibility were measured at different temperatures on two synthetic titanomagnetite samples to infer their domain structure. The samples had been prepared by double sintering and are coarse, single-phase spinels of composition: (1) Fe2.4Ti0.6O4 (``TM60'') and (2) Fe2.26Ti0.6Al0.06Mg0.06Mn0.02O4, simulating Ti content and minor cation substitution typical in oceanic Layer 2 basalts. Samples 1 and 2 gave similar results except for Curie point (Tc = 162 and 100°C). The susceptibility vs. temperature (k-T) curves are nearly reversible, k rising from -196°C by factors of 15 and 40, respectively, to a sharp peak just below Tc. At 20°C, both samples exhibit Rayleigh loops in 1.0 mT fields and show narrow hysteresis loops in 120 mT, expanding at -196°C to wide loops with respective 11- and 16-fold increases in coercivity and an increase in the ratio of remanent to saturation magnetization from 0.1 at 20°C to 0.8 at -196°C in both cases.
These results closely resemble the ``Type 1'' behavior found in some oceanic basalts containing coarse TM60, which we consider to be incompatible with (initially expected) multi-domain behavior while supporting the presence, at 20°C, of hyperfine particles showing some superparamagnetic properties that become stable single-domain properties upon cooling. This surprising magnetic behavior seems to be little affected by the presence of several percent of Al, Mg and Mn in the titanomagnetite lattice.

Affiliated with

Also associated with

No associations

Rating

Apparent superparamagnetic behavior of some coarse-grained synthetic titanomagnetite does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Apparent superparamagnetic behavior of some coarse-grained synthetic titanomagnetite, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparent superparamagnetic behavior of some coarse-grained synthetic titanomagnetite will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1690360