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At least 91 records · Page 5

Cobalt-tungsten, ferromagnetic high-temperature alloy

Cobalt-base alloy which combines high temperature strength and magnetic properties has a composition in weight percent of 7-1/2 tungsten, 2-1/2 iron, 1 titanium, 1/2 zirconium, 1/2 carbon, and the balance cobalt. It may be used as construction material for electric motors and generators operating at high temperatures.

Ashbrook, R. L.

Study of ferromagnetic liquid

Synthesis and modification of stable colloidal dispersions with strong magnetic responses and Newtonian viscosity

Kaiser, R.

Ferromagnetic-fluid logic devices

Logic element switches flows of low pressure process control fluid in fluidics assemblies. Device operates both electrically and fluidically and is controlled by passing permanent magnet or electromagnet over elements, thus providing proximity switching functions.

Makowski, M. J.

Calculation of body-centered-cubic lattice sums with an application to ferromagnetism.

The lattice sums for the bcc lattice are recalculated using the method of Flax and Raich to obtain more general expressions, valid for all temperatures, in terms of a Langevin function and its derivatives. Formulas are presented which enable easy numerical evaluation. A comparison with well-known low-temperature expansions and with the results of direct numerical integration demonstrates the validity at low temperatures of the more general expressions calculated here.

Wintucky, E. G.

Ferromagnetic phases of lunar fines and breccias - Electron magnetic resonance spectra of Apollo 16 samples

Electron magnetic resonance measurements have been made at 9 GHz and at temperatures from 1.2 to 400 K and 35 GHz (300 K) on samples of fines and breccias from Apollo 11-16. Unsorted Apollo 16 fines (less than 1 mm) have Delta H (average) = 580 G and specific intensities that have the same range as fines from the other Apollo collections. The magnetic properties of the 'characteristic' resonance are not in accord with those of iron particles. On the bases of the properties of the 'characteristic' resonance as a function of temperature and Apollo site, laboratory heat treatments on synthetic materials and lunar crystalline rocks and a comparison with the 'characteristic' resonance of the resonance spectra of breccia specimens for which iron particle sizes have been determined from other measurements, it is suggested that some fraction (about 20%) of the 'characteristic' resonance is due to sub-micron particles of ferric oxide phases.

Weeks, R. A.

Ferromagnetic phase-mass equivalence and lunar sample magnetic remanence

Man-made alloy spheres simulating the compositions of particles found in the lunar soil and weighting approximately 10 mg are shown to be equivalent, insofar as remanence intensity and demagnetization stability are concerned, to more than about 10 billion submicrometer spherical iron particles. The large particles not only contain large stable magnetic remanence, but when the polished surfaces of these particles are etched and carefully studied, they provide useful petrogenetic information, imply the mechanism of magnetization, the time-temperature history, and outline the format for possible paleointensity analysis. The intensity and stability of the remanence in these large spheres is related to the microstructure developed during rapid cooling.

Wasilewski, P. J.