Fabrication of divertor mock-up with ODS-Cu and W by the improved brazing technique
Fabrication of divertor mock-up with ODS-Cu and W by the improved brazing technique
复制标题
通过改进的钎焊技术用 ODS-Cu 和 W 制作偏滤器模型
DOI：
10.1088/1741-4326/aa6bb3
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发表时间：
2017
期刊：
影响因子：
3.3
通讯作者：
FFHR Design Group
中科院分区：
文献类型：
--
作者：
M. Tokitani;Y. Hamaji;Y. Hiraoka;S. Masuzaki;H. Tamura;H. Noto;T. Tanaka;T. Muroga;A. Sagara;FFHR Design Group
铜合金具有较高的导热系数，不仅在FFHR-D1型螺旋堆中被用作偏滤器冷却管或散热器，在托卡马克演示堆中也被认为是一种散热器。研究了氧化物弥散强化铜合金GlidCop®(Cu-0.3wt%Al_2O_3)作为FFHR-D_1偏滤器散热材料的应用。该合金在室温下经~1000℃退火后仍具有超过300 Mpa的高温屈服强度。本文综述了Pure-Cu、GlidCop®和CuCrZr在中子辐照后材料性能的变化。主要剂量极限是辐射诱导的硬化/软化(~0.2dpa/1-2dpa)，它具有温度依赖性。根据这样的评估，GlidCop®可以被选为目前偏滤器散热器商用底座的最佳候选材料，并且在运行期间其温度应尽可能保持在接近300℃的水平。W装甲和GlidCop®散热器之间的连接是通过使用改进的BNi6(Ni-11%P)填充材料的铜焊技术成功实现的。通过三点弯曲试验测得粘接强度高达200 Mpa左右。令人惊讶的是，有几个样本显示出明显的屈服点。这意味着BNI-6钎焊(粘合)层导致了施加的应力松弛。采用改进的钎焊工艺，成功地制作了W/BNi-6/GlidCop®偏滤器模型。热负荷试验是在NIFS的ACT2电子束装置上进行的。该模型在FFHR-D1型偏滤器上表现出良好的散热能力。
Copper alloy has been considered as a divertor cooling tube or heat sink not only in the helical reactor FFHR-d1 but also in the tokamak DEMO reactor, because it has a high thermal conductivity. This work focused on applying an oxide dispersion strengthened copper alloy (ODS-Cu), GlidCop®(Cu-0.3 wt% Al 2 O 3) as the divertor heat sink material of FFHR-d1. This alloy has superior high temperature yield strength exceeding 300 MPa at room temperature even after annealing up to~ 1000 C. The change in material properties of Pure-Cu, GlidCop® and CuCrZr by neutron irradiation are summarized in this paper. A primary dose limit is the radiation-induced hardening/softening (~ 0.2 dpa/1–2 dpa) which has a temperature dependence. According to such an evaluation, the GlidCop® can be selected as the current best candidate material in the commercial base of the divertor heat sink, and its temperature should be maintained as close as possible to 300 C during operation. Bonding between the W armour and the GlidCop® heat sink was successfully performed by using an improved brazing technique with BNi-6 (Ni-11% P) filler material. The bonding strength was measured by a three-point bending test and reached up to approximately 200 MPa. Surprisingly, several specimens showed an obvious yield point. This means that the BNi-6 brazing (bonding) layer caused relaxation of the applied stress. The small-scale divertor mock-up of the W/BNi-6/GlidCop® was successfully fabricated by using the improved brazing technique. The heat loading test was carried out by the electron beam device ACT2 in NIFS. The mock-up showed an excellent heat removal capability for use in the FFHR-d1 divertor.