聚变堆用N-ODS复合结构材料的阻氚与增韧机理研究

ODS steel is one of the most promising structural materials in fusion reactor, but the brittleness at room temperature, permeation and retention of deuterium and tritium are major problem it faces. We research composition optimization, layered toughening technology and hydrogen (deuterium, tritium) resistance technology and mechanism and effect anti-ion irradiation property in this program. We prepared N-ODS steel by optimizing the composition, adding different kind of nitrogen sources to improve its strength and toughness. Then we developed “N-ODS steel/TiN ceramic/metal Ta” and “N-ODS steel/metal Ta” layered composites. High ductility of Ta laminate and layered toughening technology are used to improve the strength and toughness, and realize the tritium permeation resistance function by depositing TiN or in-situ generate TaN coating on metal Ta. In this project, we will carry out an in-depth study on the mechanisms of toughening and tritium permeation resistance of these two layered systems. Illuminate the damage mechanisms under transient thermal shock, and the adsorption, diffusion and retention behavior of hydrogen (deuterium, tritium) in the composite system. Illuminate the influence mechanisms on hydrogen (deuterium, tritium) behavior of interstitial atom (N atom), ion irradiation, second-phase nanoclusters and particles except for TiN and TaN ceramic coating and the interface in the composite system. To add new knowledge for nuclear fusion research and lay a foundation for exploring a new generation of structural materials.

ODS钢是聚变反应堆候选结构材料之一，脆性和氢（氘、氚）的渗透和滞留等是其面临的重大技术难题，本项目拟研究ODS钢的成分优化、层状增韧、阻氢（氘、氚）技术和机理及抗离子辐照性能。添加各种氮源，制备N-ODS钢，改善其强韧性，设计“N-ODS钢/TiN陶瓷/金属Ta片”与“N-ODS钢/金属Ta片”两种层状复合体系，利用高塑形的Ta片和层状强韧化机制提高强韧性。在内置多层Ta片的表面沉积TiN或原位生成TaN薄膜实现多重阻氚功能。本项目拟对两种层状体系深入开展增韧和阻氚机理研究，阐明复合体系在瞬态热冲击下的损伤机制，氢（氘、氚）在复合体系中的吸附、扩散和滞留等物理行为，揭示间隙原子（N原子）、离子辐照、第二相纳米团簇和颗粒的数量和类型等以及复合体系中多层TiN和TaN陶瓷层及层间界面对氢（氘、氚）行为的影响机制。为核聚变研究增加新知识，给开发新一代结构材料奠定基础。

ODS钢是聚变反应堆候选结构材料之一，脆性和氢（氘、氚）的渗透和滞留等是其面临的重大技术难题，本项目对ODS钢的成分优化、层状增韧、阻氢（氘、氚）技术和机理及抗离子辐照性能进行了研究。通过不同氮源向ODS钢中引入N元素，制备N-ODS钢，改善了其强韧性与阻氢（氘、氚）性能，得到一种抗拉强度1477.46MPa，断裂延伸率为6.7%的N-ODS钢，其氘渗透率 Φ=6.78x10-9exp(-45254(J/mol-1)/RT)，明显低于现有RAFM钢，对其增韧、阻氢（氘、氚）一体化的机理进行了研究，对其抗辐照性能的研究正在进行。设计制备了“N-ODS钢/TiN陶瓷/金属Ta片”与“N-ODS钢/金属Ta片”两种层状复合体系，利用塑形的Ta片和层状强韧化机制提高了材料韧性，并通过内置的多层Ta片和原位生成Ta（C，N）薄膜实现了多重阻氚功能，制得的N-ODS/TiN/Ta复合材料抗最佳拉强度1085MPa，断裂延伸率8.2%；制得的N-ODS/Ta复合材料最佳抗拉强度1211MPa，断裂延伸率10.3%，其氘渗透率 Φ=6.33x10-10exp(-63527(J/mol-1)/RT)，比N-ODS低一个数量级。两种复合材料抗热冲击性能较差，易在退火过程中开裂。对氢（氘、氚）在复合体系中的吸附、扩散和滞留等物理行为进行了探究，揭示了间原子（N原子）、第二相纳米团簇和颗粒的数量和类型等以及复合体系中陶瓷层及层间界面对氢（氘、氚）行为的影响。为核聚变研究增加新知识，给开发新一代结构材料奠定基础。