Patent Number: 046844805
Section: abstract

The invention is a ceramically-bonded large-area neutron absorber articles of low density having a space filling of. about 40 to 60% by volume boron carbide+silicon carbide in a B.sub.4 C:SiC ratio of about 9:1 to 1:9 and PA1 about 10 to 20% by volume of free carbon, the remainder pores.. They have a density of from about 1.5 to 2.2 g/cm.sup.3 and a flexural strength of from about 20 to 50 N/mm.sup.2 at room temperature measured according to the 3-point method, which strength after the corrosion test of immersion for about 3000 hours in boiling water, drops by less than about 40% of the initial value. Graphite powder may optionally be included with a pulverulent organic resin binder and a wetting agent, molding the mixture under pressure at about room temperature, curing the resin binder at temperatures of up to about 180.degree. C. and then coking the molded plates in the absence of air at temperatures of up to about 1000.degree. C. under a controlled temperature program.