有序3D微结构大电流高压真空触头材料的设计、制备及相关物理问题

Because of its small volume, easy maintenance and non-pollution, the vacuum circuit breaker is widely applied in medium-low voltage power networks. But there are some problems needed to be solved in 126 kV or above vacuum circuit breaker, such as strong arc ablation on several local zones and temperature rise et al. Therefore, the developing of high voltage and large current vacuum contact materials will meet the development strategies of energy conservation and environmental protection in smart grid. One of the solutions is to control the vacuum arc cathode spot by magnetic field, because the Cr phase is disordered in conventional CuCr contact materials. In this project, 3D knitting technology will be used to prepared contact composite materials with diversion microstructure which is composed of high conductive phase Cu, arc ablation resistance phase Cr and soft magnetic phase Fe. A magnetic field with diversion function will be achieved in the designed contact materials, in which conductive phase and arc ablation resistance phase will be changed from disorder to order. The arc cathode spot will moved quickly driven by the large magnetic field in-situ generated on the surface of contact materials. The purpose is to study the effect of in-situ generated magnetic field by 3D microstructure on the distribution and motion of arc cathode spot. Optimized scheme and control method of 3D microstructure in contact materials will be proposed to improve the ability of breaking current and voltage breakdown resistance. Based on the results, high performance contact materials applied in 126 kV or above single break vacuum circuit breaker will be developed.

真空断路器具有体积小、易维护、无污染的优点，广泛应用于中低压电网，但对于126kV及以上电压等级无法解决触头材料电弧不均匀的局部严重烧蚀和温升等问题，因此突破可应用于高电压、大电流的真空断路器触头材料，符合智能电网节能环保的发展战略。通过传统粉末冶金生产的CuCr触头材料中耐电弧烧蚀相Cr为无序状态，只能通过外部设计实现磁场对真空电弧阴极斑点的有效控制。本项目拟通过3D编织技术制备具有高导电相Cu、耐电弧烧蚀相Cr、软磁相Fe组成的具有导流微结构的复合触头材料，将导流相和耐电弧烧蚀相由无序变为有序，实现触头材料和导流磁场一体化结构设计，在触头表层原位产生大磁场驱动阴极斑点的快速运动，研究和揭示3D微结构原位产生磁场对阴极斑点分布和运动的影响机理，提出触头材料微结构优化设计方案和控制手段，提高触头的分断电流能力和耐电压击穿能力，开发出单断口高性能126kV以上高电压等级新一代触头材料。

真空断路器具有体积小、易维护、无污染的优点，广泛应用于中低压电网，但对于126kV 及以上电压等级无法解决触头材料电弧不均匀的局部严重烧蚀和温升等问题，因此突破可应用于高电压、大电流的真空断路器触头材料，符合智能电网节能环保的发展战略。过传统粉末冶金生产的CuCr触头材料中耐电弧烧蚀相Cr为无序状态，只能通过外部设计实现磁场对真空电弧阴极斑点的有效控制。本项目拟制备具有高导电相Cu、耐电弧烧蚀相Cr、软磁相Fe组成的具有导流微结构的复合触头材料，将导流相和耐电弧烧蚀相由无序变为有序，实现触头材料和导流磁场一体化结构设计，在触头表层原位产生大磁场驱动阴极斑点的快速运动。经过4年研究，研究过程按计划进行，基本达到了预期研究目标。研究和揭示了3D微结构原位产生磁场对阴极斑点分布和运动的影响机理，提出了触头材料微结构优化设计方案和控制手段，提高了触头的分断电流能力和耐电压击穿能力，开发出单断口高性能126kV以上高电压等级新一代触头材料。在项目的支持下培养了博士后人员2人、博士研究生2人、硕士研究生13人，发表论文37篇，其中SCI收录论文35篇，授权国家发明专利10项，项目组成员参与并获得陕西省科技进步一等奖1项、陕西省自然科学二等奖1项、陕西高等学校科学技术奖一等奖1项。