Nuclear fuel rods are made of hundreds of small pellets of enriched uranium placed end - to - end inside hollow tubes of zircaloy that are about a half - inch across. (sciencedaily.com)
While zircaloy loses strength as temperature increases — becoming 2 percent weaker for every 10 C increase in temperature and losing all strength at about 1300 C, Stempien says — the strength of the SiC ceramic remains essentially constant to temperatures well above 1500 C. (sciencedaily.com)
When it gets hot enough, zircaloy reacts with steam to produce hydrogen, a hazard in any loss - of - coolant nuclear accident. (sciencedaily.com)