Process for determining impurities in refractory materials
AssigneeAgere Systems Optoelectronics Guardian Corp.
InventorWilliam David Reents, Jr.
Life of this patent
Estimating the term…
Abstract
A small sample of a refractory material, e.g., about 0.1 g to about 10 g, is heated to at least 1000° C., generally under a pressure of less than about 10−5 Torr. Evolved hydrogen-containing gases and/or carbon-containing gases are monitored, e.g., by mass spectrometry, and, based on the amount of the evolved gases, the concentration of hydrogen and/or carbon in the sample is calculated. It is therefore possible to accurately determine the hydrogen and carbon concentration from a small sample of a material, by a process much less burdensome than conventional techniques.
Claims8
A process for fabricating a refractory article, comprising the steps of:
- (a) heating a silica sample to at least 1000° C.;
- (b) monitoring at least one of evolved hydrogen-containing gases and evolved carbon-containing gases;
- (c) cooling the sample and adding hydrogen to the cooled sample;
- (d) subsequent to adding hydrogen, reheating the sample to at least 1000° C. and monitoring evolved carbon-containing gases;
- (e) optionally repeating steps (c) and (d);
- and
- (f) based on the amount of the evolved gases, calculating the concentration of at least one of hydrogen and carbon in the sample.
A process for fabricating a refractory article, comprising the steps of:
- heating a silica body to at least 1000° C.;
- cooling the body and adding hydrogen to the cooled body;
- and
- subsequent to adding hydrogen, reheating the body to at least 1000° C.,
- wherein the added hydrogen promotes evolution of carbon-containing species from the body.
Dependencies are inferred from the claim text.