利用加速器产生的电子束（ＥＢ）在空气中辐照聚碳硅烷（ＰＣＳ），以使之形成交联结构，然后经高温热解转化成ＳｉＣ陶瓷。结果表明：在辐照产物中形成了ＳｉＣＳｉ以及ＳｉＯＳｉ等交联结构，热解温度以及热解陶瓷产率都随辐射吸收剂量增加而明显提高。通过ＴＧＩＲ联用分析技术，在热解产物中检测到了低分子量ＰＣＳ以及ＣＨ４等小分子化合物，在吸收剂量高于２．３ＭＧｙ时，ＰＣＳ主要通过析出ＣＨ４而热解成ＳｉＣ。 The polycarbosilane (PCS) was irradiated in air with an electron beam (EB) generated by an accelerator so as to form a crosslinked structure and then pyrolytically converted into SiC ceramics by high temperature. The results showed that the cross-linked SiCSi and SiOSi structures were formed in the irradiated product. The pyrolysis temperature and the yield of pyrolytic ceramics increased with the increase of radiation absorbed dose. Low-molecular-weight PCS and small molecular compounds such as CH4 were detected in pyrolysis products by TG-IR analysis. When the absorbed dose was higher than 2.3MGy, PCS was mainly pyrolyzed into SiC by precipitation of CH4.