为研究炭化和高温纯化等热处理对高温气冷堆球形燃料元件酚醛树脂炭性能的影响,对比分析了炭化后及高温纯化后树脂炭的微观组织和物理性能。结果表明,与炭化后的树脂炭相比,经高温纯化后的树脂炭具有更高的石墨化有序程度,树脂炭内微孔的平均孔径增大,比表面积降低超过50%。在723、773、823和873 K温度下,干燥空气中高温纯化后的树脂炭具有较低的氧化速率,表现出更佳的抗氧化腐蚀性能。高温纯化后树脂炭石墨化有序程度的提高有利于提高球形燃料元件的综合性能。
In order to study the effects of heat treatments such as the carbonization and high temperature purification (HTP) on the properties of phenol resin (PR) carbon of pebble fuel elements for HTGR , the micro‐structure and physical properties of PR carbon after carbonization and further HTP were comparatively analyzed .The results indicate that comparing with the PR carbon obtained by carbonization ,the PR carbon treated with further HTP exhibits higher degree of graphitization and larger average pore size ,and has specific surface area of less than 50% .In the dry air atmosphere ,the PR carbon treated with further HTP possesses lower oxidation rate and higher oxidation resistance property . The improvement of graphitization degree of PR carbon with further heat treatment of HTP is beneficial to upgrade the integrated properties of pebble fuel elements .