The behavior of mixed uranium-plutonium nitride fuel and uranium nitride was studied by means of thermogravimetry at high temperatures (to 2173 K) in a helium flow. The mass loss of the nitride samples was found in the low temperature range (<1773 K), which is not associated with decomposition of uranium or plutonium mononitrides. The mass loss occurs in two stages and is accompanied by the release of nitrogen. It is shown that nitride fuel can contain up to several percent of uranium sesquinitride U₂N₃, which decomposes in the indicated temperature range and can strongly affect pellet integrity and fuel-rod life during operation.

中文翻译：

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氮化核燃料结构和相组成对燃料棒寿命的影响

通过热重法在高温（至2173 K）下在氦气流中研究了铀-p-氮化铀混合燃料和氮化铀的行为。发现氮化物样品的质量损失在低温范围（<1773 K）下，这与铀或mono一氮化物的分解无关。质量损失分两个阶段发生，并伴随着氮的释放。结果表明，氮化物燃料最多可包含百分之几的次生氰化铀U ₂ N ₃，该铀在指定的温度范围内会分解，并且在运行过程中会严重影响颗粒完整性和燃料棒寿命。