医用重离子加速器U型碳剥离膜的研制  

Development of U-shaped carbon foil in medical heavy ion accelerator

作　　者：刘凤琼[1] 卢子伟[1] 张宏斌[1] 戎欣娟[1] 李荣华[1] 李海霞[1] 李占奎[1] 王秀华[1] LIU Fengqiong;LU Ziwei;ZHANG Hongbin;RONG Xinjuan;LI Ronghua;LI Haixia;LI Zhankui;WANG Xiuhua(Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China)

机构地区：[1]中国科学院近代物理研究所

出　　处：《核技术》2019年第10期1-5,共5页Nuclear Techniques

基　　金：国家自然科学基金(No.11775283、No.U1832149)资助~~

摘　　要：碳剥离膜作为剥离器的核心组成部件是医用重离子加速器的重要装置之一,研制出满足医用重离子加速器要求的碳剥离膜至关重要。采用交流弧光放电法完成了医用重离子加速器中碳剥离膜的研制,并用扫描电子显微镜和拉曼表征手段测试分析了碳剥离膜的薄膜特性。为了不影响已注入环中离子的正常运行,靶框设计为U型,靶边框较窄仅为2 mm,碳剥离膜的有效面积为1 600 mm(2 40 mm×40 mm)。碳剥离膜的厚度为15μg·cm^?2,理论计算结果表明该碳剥离膜的厚度均匀性为97.65%。碳剥离膜具有一定的机械韧性,可以完成碳剥离膜的自动换膜过程,且在自动换膜过程中无破裂损伤。扫描电子显微镜观测结果显示:碳剥离膜的表面平整,内部结构致密。拉曼测试结果表明:位于1 580 cm^?1附近的G峰明显强于位于1 300 cm^?1附近的D峰,说明薄膜的石墨化程度较高;2 700 cm^?1左右的2D峰较弱,说明石墨分子层数较多。[Background]Carbon stripping foil as a stripper is one of the important components of medical heavy ion accelerator.It is essential to develop the carbon stripping foil that meets the requirements of medical heavy ion accelerators.[Purpose]This study aims to develop U-shaped carbon foil for medical heavy ion accelerator.[Methods]AC carbon arc discharge method was employed to develop the carbon stripping foil,and its properties were measured by the methods of scanning electron microscopy(SEM)and Raman characterization.The"U-shaped"target frame was used to ensure that target frame did not affect the normal operation of ions in the injected ring.The edge of target frame was designed to be as narrow as 2 mm wide,and the effective area of the carbon stripping foil was 1 600 mm2(40 mm×40 mm).[Results]The thickness of the carbon stripping foil is 15μg·cm^?2,and the thickness uniformity is 97.65%.The SEM test results show that the surface of the carbon stripping film is smooth and the internal structure is compact.The Raman test results show that the G peak near 1 580 cm^?1 is stronger than the D peak located near 1 300 cm^?1,indicating the degree of graphitization of the film is higher,and the 2D peak near 2 700 cm^?1 is weak,indicating that the number of graphite molecules is higher.[Conclusion]The carbon stripping foil developed in this study has a certain mechanical toughness thereby completing the automatic mold changing process of the carbon stripping foil.

关 键 词：碳剥离膜 U型靶框 扫描电子显微镜 拉曼 

分 类 号：TL99[核科学技术—核技术及应用]