紧凑型氘氘中子发生器中钛自成靶实验研究

Experimental Study of Titanium Driven-in Targets in Compact D-D Neutron Generator

靶作为氘氘中子发生器关键部件之一,其性能直接影响了中子发生器的中子产额及其稳定运行。文章从钛自成靶的设计、制备、表征及测试四个方面系统的介绍了中子发生器中靶的关键技术实验研究。首先,为满足靶的温度控制需求,采用无氧铜作为靶基底材料,并在其内部开设套环式主动水冷回路。通过ANSYS热工模拟靶在加速器运行时的表面温升情况,并利用电子枪轰击测试靶表面实际温度变化情况。模拟和测试结果表明,在中子发生器运行期间,靶表面温度可以有效控制在200℃以内。随后,利用直流磁控溅射技术在无氧铜靶衬底表面制备微米级高纯靶膜。并且,利用扫描电子显微镜、能谱仪、X射线衍射仪和划痕仪研究了靶膜表面的微观结构、成分及膜基结合力。结果表明利用磁控溅射制备的钛膜表面十分均匀紧凑,以六方晶系结构的α-Ti沉积在靶衬底表面,钛膜与基底的膜基结合力为0.22 N。最后,在感应耦合型中子发生器中子产额达到了1.25×10^(8)n/s,电子回旋共振中子发生器中子产额达到了1.75×10^(8)n/s,都实现了稳定运行5 h。

Deuterium target,as one of the key components in the neutron generator,directly affects the neutron yield of the neutron generator.The key issues in the design,fabrication,characteristics and experiments of the titanium drive-in target were systematically studied in this article.First,oxygen-free copper material is used for the target substrate with a dedicated water loop in order to reduce the target surface temperature during accelerator operation.According to the results of the ANSYS simulation and electron gun experiment,the target surface temperature was controlled below 200℃well during neutron generator operation.Second,a micron pure titanium film was coated on the target substrate surface through magnetron sputtering technology.The structure and properties of the titanium film were analyzed by a scanning electron microscope,an X-ray diffractometer and a nanoscratch instrument.The results showed that the titanium film was coated uniformly and densely on the surface.The adhesion between the titanium film and substrate is about 0.22 N.Finally,In the ICP neutron generator,the neutron yield reached 1.25×10^(8)n/s,and in the ECR neutron generator,the neutron yield reached 1.75×10^(8)n/s;both achieved 5 hours of stable operation.