Preparation and Neutron Yield Analysis of Large Area Deuterium/Tritium Target

Abstract

The large deuterium/tritium target is the key component to achieve high yield and high current neutron source, which is the precondition for the wide application of deuterium/tritium neutron source. At present, there are mature deuterium/tritium titanium targets in scientific or engineering applications abroad, and the neutron yield generally reaches the level of 1013/s. However, the technology of large-area target film in China is immature. The scientific and industrial application of large-area target film is rarely reported. The main problem is that the deuterium/tritium target can not reach the high yield, and the large area of the target film prepared is uneven, the binding force is poor and easy to fall off. In this paper, in order to solve the above mentioned problems and optimize the performance of the target film, magnetron sputtering coating and multi-arc ion plating were combined to prepare large-area titanium films with copper or molybdenum substrate and diameter greater than φ500 mm. At the same time, the feasibility of erbium film, scandium film and zirconium film preparation was explored by preparing large area deuterium-titanium or tritium-titanium targets with high binding force and high deuterium-tritium-titanium ratio. Deuterium and tritium targets with deuterium/tritium titanium ratio greater than 1.85 are produced by using self-developed deuterium/tritium target production system after degassing, purification, high temperature deuterium absorption, tail gas recovery and other processes. In order to better utilize the functions of each film layer, scanning electron microscopy was used to observe the cross-section of the film layer in the experiment. The results show that the clear interface is observed among the base layer, transition layer, and functional layer. The prepared titanium film was tested for neutron yield using a deuterium ion accelerator, and the effects of deuterium ion beam current and anode voltage on neutron yield were analyzed. The experiment shows that with the increase of deuterium beam current, neutron yield shows a linear increase in the range of 700 μA. The effect of anode acceleration voltage on neutron yield increases exponentially in a quadratic relationship. The neutron yield of the developed deuterium target is more than 8.0×108/s, and the neutron yield of the tritium target is estimated according to the reaction section of the deuterium target and the tritium target. Under the same conditions, the neutron yield of the tritium target is more than 1.0×1011/s. The test results show that the developed φ500 mm large area deuterium/tritium target can achieve the high-yield neutron output of the high-current neutron source, reaching the highest neutron flux of 1013/s in the world.

Keywords

• deuterium target
• tritium target
• neutron source
• neutron generator