【公開日：2025.06.10】【最終更新日：2025.05.09】
課題データ / Project Data
課題番号 / Project Issue Number
24TU0093
利用課題名 / Title
高周波超音波によるダイバータモノブロックと冷却管接合界面の欠陥検出性能に及ぼす結晶粒径増大の影響評価
利用した実施機関 / Support Institute
東北大学 / Tohoku Univ.
機関外・機関内の利用 / External or Internal Use
内部利用（ARIM事業参画者以外）/Internal Use (by non ARIM members)
技術領域 / Technology Area
【横断技術領域 / Cross-Technology Area】（主 / Main）加工・デバイスプロセス/Nanofabrication（副 / Sub）計測・分析/Advanced Characterization
【重要技術領域 / Important Technology Area】（主 / Main）高度なデバイス機能の発現を可能とするマテリアル/Materials allowing high-level device functions to be performed（副 / Sub）-
キーワード / Keywords
超音波顕微鏡,超音波検査,高品質プロセス材料/技術/ High quality process materials/technique
利用者と利用形態 / User and Support Type
利用者名（課題申請者）/ User Name (Project Applicant)
ファリダフシン モハンマドジャバド
所属名 / Affiliation
東北大学大学院工学研究科
共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes
ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes
利用形態 / Support Type
（主 / Main）機器利用/Equipment Utilization（副 / Sub）-
利用した主な設備 / Equipment Used in This Project
報告書データ / Report
概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)
This study analyzed the influence of local grain enlargement of Oxygen-Free Copper (OFCu) on the defect detection performance of High-Frequency Ultrasonic Testing (HF-UT). Plate OFCu samples were heat treated in several conditions to have different grain structures. Nine holes were drilled on one side of the samples to simulate defects, and better analyze the effect of local grain enlargement on the detection performance of HF-UT. The results show that local grain enlargement has a considerable influence on the defect detection performance of HF-UT. It was shown that the holes located in the vicinity of the local grain enlargements have a lower visibility compared to the holes located in areas with no local grain enlargement, and that local grain enlargement increase the false alarm rate.
実験 / Experimental
Ten OFCu plates with different heat treatment conditions were prepared to investigate the influence of grain enlargement on the defect detection performance of HF-UT. To simulate defects ate the OFCu side in the W-OFCu bonded interface of the divertor’s cooling pipe, nine equally spaced holes were drilled on one side of each sample. The samples were measured approximately 30 mm × 30 mm × 3 mm respectively. Figure 1 schematically shows the OFCu samples that contained drilled holes with diameters d1, d2, and d3 and depths h1, h2, and h3 and numbered as D1, D2, D3, D4, D5, D6, D7, D8, and D9 according to Fig. 2. Tables 1 and 2 summarize the parameters of the drilled holes for OFCu, and heat treatment conditions of the samples.
結果と考察 / Results and Discussion
Figure 3, 4, 5, 6, and 7, contain microscopic images and average grain areas of samples OFCu2-2, OFCu2-4, OFCu2-6, OFCu2-7, OFCu2-8, and OFCu2-10 with heat treatment conditions summarized in Table 2. Figures 3, 4, 5, 6, and 7 show that extreme grain enlargements have occurred for the samples after heat treatment, with the average grain areas being equal to 1.5 × 10-1 mm2 for OFCu2-2, 9 × 10-2 mm2 for OFCu2-4, 7 × 10-2 mm2 for OFCu2-6, 1.6 × 10-1 mm2 for OFCu2-7, 1.2 × 10-1 mm2 for OFCu2-8, and 3.6 × 10-2 mm2 for OFCu2-10. To confirm the local grain enlargements, Figs. 8, 9, 10, 11, 12, and 13 show whole-view images of the surface of the samples, and indicate that the largest local grain enlargements have occurred for samples OFCu2-7, OFCu2-8, and OFCu2-10 in the areas marked by the red dashed rectangles. Figures 14, and 15, show C-scans of OFCu2-1, OFCu2-2, with d1 = d2 = d3 = 5 mm and h1 = h2 = h3 = 0.5; Figs. 16, and 17, show C-scans of samples OFCu2-3, and OFCu2-4 with d1 = d2 = d3 = 3 mm and h1 = h2 = h3 = 0.3 mm, the C-scans of Figs. 18, and 19 belong to samples OFCu2-5, and OFCu2-6 with d1 = d2 = d3 = 1 mm and h1 = h2 = h3 = 0.1 mm, and the C-scans of Figs. 20 and 21 belong to samples OFCu2-7 with d1 = d2 = d3 = 5 mm and h1 = h2 = h3 = 0.5 and OFCu2-8 with d1 = d2 = d3 = 3 mm and h1 = h2 = h3 = 0.3; C-scans of Figs. 22 and 23 belongs to samples OFCu2-9, and OFCu2-10 with d1 = 1 mm, d2 = 3 mm, d3 = 3 mm, h1 = 0.5 mm, h2 = 0.3 mm, h3 = 0.1 mm. The indication of drilled holes in the C-scan images are encircled by red dashed lines and are numbered according to Fig. 2. The Time-of-Flight (ToF) ranges used to make the images were selected between 0.9 μs – 1.35 μs that approximately corresponds to 2 mm – 3 mm so that the images include the backwall echoes and the echoes from the holes.
図・表・数式 / Figures, Tables and Equations
Fig. 1. Schematic of the backwall of OFCu plates with drilled holes on their side with diameters d1, d2, and d3, and depths h1, h2, and h3.
Fig. 2. Schematic of the backwall of OFCu plates with drilled holes on their side numbered as D1, D2, D3, D4, D5, D6, D7, D8, D9.
Table 1. Properties of the drilled holes on OFCu samples.
Table 2. Heat treatment conditions of the samples.
Fig. 3. Microscopic image OFCu2-2.
Fig. 4. Microscopic image OFCu2-4.
Fig. 5. Microscopic image OFCu2-6.
Fig. ６. Microscopic image of OFCu2-7.
Fig. 7. Microscopic image of OFCu2-8.
Fig. 8. Whole view image of OFCu2-2.
Fig. 9. Whole view image of OFCu2-4.
Fig. 10. Whole view image of OFCu2-6.
Fig. 11. Whole view image of (d) OFCu2-7,
Fig. 12. Whole view image OFCu2-8.
Fig. 13. Whole view images of OFCu2-10.
Fig. 14. C-scan image OFCu2-1 at 35 MHz frequency.
Fig. 15. C-scan image of OFCu2-2 at 35 MHz frequency.
Fig. 16. C-scan image of OFCu2-3 at 35 MHz frequency.
Fig. 17. C-scan image of OFCu2-4 at 35 MHz frequency.
Fig. 18. C-scan image of OFCu2-5 35 MHz frequency.
Fig. 19. C-scan image of OFCu2-6 at 35 MHz frequency.
Fig. 20. C-scan image of OFCu2-7 with local grain enlargements.
Fig. 21. C-scan image of OFCu2-8 with local grain enlargements.
Fig. 22. C-scan image of OFCu2-9 at 35 MHz frequency.
Fig. 23. C-scan image of OFCu2-10 at 35 MHz frequency.
その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)
This study analyzed the influence of grain enlargement of OFCu on the defect detection performance of HF-UT. It was shown that signal fluctuations and reduction of amplitude of ultrasonic waves because of ultrasonic attenuation due to grain enlargements reduce the general visibility of defects in the C-scan images. Local grain enlargements were observed to sizes several times larger than the thickness of the block OFCu samples. The results indicated that the defects of the same size had a lower visibility when they were located in the vicinity of the locally enlarged grains. It was also shown that local grain enlargement leads to false alarms about the size, shape, and the presence of the defects.
成果発表・成果利用 / Publication and Patents
論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)
口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.
特許 / Patents
特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件