| 摘要 |
<p>A process, and the compositions produced thereby, wherein an element characterized as aluminum, silicon or chromium, notably aluminum, is alloyed in relatively small concentrations with iron, cobalt or nickel, notably iron or cobalt, or both, which have relatively high Curie temperatures. Small amounts of yttrium, hafnium, zirconium or lanthanum can also be added. Alloys of specified composition are formed into particles of selected size, and the particles then contacted in an atmosphere of controlled oxygen activity at elevated temperature over selected time periods to form an impervious oxide film of critical thickness. The compositions may be used as such or as inclusions for the preparation of catalytic or non-catalytic magnetizable solids composites for use in magnetically stabilized fluidized beds for high temperature reactions such as hydro-forming processes or in use as fluid bed fly-ash filters.</p> |
