日本国内の放射光施設が建設されてから久しいが、新たな施設建設も進行している。今後も放射光を利用した材料評価の研究と利用は継続発展するものと思う。前項では、量子ビーム (放射光および中性子 )を利用した応力・ひずみ評価の基礎的事項について説明した。本稿では、高エネルギー放射光を応用したテーマとして、コーティングの残留応力、溶接および粗大粒の問題について紹介する。また、分光器から得られる単色Ｘ線による応力評価について述べる。放射光白色Ｘ線を利用した応力評価については、次の「放射光の応用 2」にて取り扱う。...

Non-destructive examination (NDE) methods for joint interfaces between different materials in high heat flux components of ITER divertor should be urgently developed to assure qualit y and reliability of joining techniques. This paper reports the present R&Ds status of NDE for ITER divertor and its outlook. The detection ability of joint defect by using ultrasonic wave and thermography NDE are examined in the joint interface between armor tiles and a cooling tubes of divertor mock-ups. The results of both ...
英字タイトル:
Development of Non-destructive technique for ITER divertor high heat flux component

極微の世界では，粒子性と波動性を併せ持つ振る舞いがみられ、その性質を量子性という。その粒子には、光子、中性子、素粒子などがある。研究炉や加速器などの量子ビーム施設を有効かつ積極的に利用することで，新たな科学技術を切り拓くことが期待されている。 本特集では、材料評価のプローブとして利用される光子 (電磁波 )および中性子を利用した量子ビームの研究として、シンクロトロン放射光および中性子回折を利用した材料評価 (応力・ひずみ )を紹介する。...

西川 聡 Satoru NISHIKAWA Welding is widely used as a joint method of large structures. The residual stress which is the inevitable consequence of welding causes fatigue fracture or stress corrosion crackin g (SCC). In this study, the residual stresses of the dissimilar butt welding joint, which was fabricated between SUS316L and NCF600, were simulated using the finite element method. The distributions of the residual stress of the butt welding joint were anti-symmetry. The welded part had the large tensile ...
英字タイトル:
Simulation of residual stresses of dissimilar welding joint

In this study, a residual stress distribution in a dissimilar plate butt-welded joint was simulated by a thermo-elastic finite element method. The base metal was the austenitic stainless steel SUS316L. The other base metal was nickel super-alloy NCF600, and the weld metal was the alloy 82 (YNiCr-3). The dimensions of the plate butt-welded joint were a width of 200 mm, a length of 250 mm and a thickness of 25 mm. The welding joint was fabricated by TIG welding with 22 passes. For comparison, the residu...
英字タイトル:
Residual Stresses in Dissimilar Metal Joint by Multi-pass Welds

This paper describes a stress measurement using a direct-method. In the direct-method, the stress is measured by the normal incident X-ray beam, one exposure and an area detector. The direct-method needs a narrow incident beam, so that the beam was made by the graphite monochromator. The welded specimen of SUS316L and the shrink-fitted specimen of SUS304 were prepared, and the distributions of the residual stresses of these specimens were measured using the direct-method. It was possible to measure the weld ...
英字タイトル:
Residual Stress Measurements using Direct-Method

応力腐食割れ (SCC) のき裂の発生,進展においては,表面から内部応力の応力評価が不可欠である. 一 一般のX線応力測定法は, 等方均質な多結晶体を前提と した方法である1). 粗大粒の応力測定の研究 2) も進め られているが,それで解決できない場合も多い。例え ば,溶接部は粗大粒かつ集合組織を持ち,従来のX線 応力測定標準がどこまで適用できるかを検討してい る所である3),一方,内部の非破壊的な応力測定も要求される.内 部の応力測定では,中性子線が優れた方法といえる が,中性子束の強度が小さいために長時間を要する. また,中性子応力測定のゲージ体積も 1mm の寸法と 空間分解能が大きいために表面付近を測定するには, 改善する必要がある.それに対し,高エネルギー放射 光は高輝度かつ十分な透過力を持つので,10mm 以内 の内部であれば,um オーダーの空間分解能で測定可 能である.しかし,いずれにしても粗大粒の問題を解 決する必要がある. 1. 本提案では,粗大粒のための高エネルギー放射光X 線を利用した応力測定を提案する...
英字タイトル:
Internal Stress Measurement for Coarse Grains

In this study, creviced bent beam (CBB) test, x-ray stress measurement, and hardness testing on a specimen made of Type 316L stainless steel with controlled plastic strain distribution were carried out in order t o clarify behavior of crack initiation and effects of plastic strain and stress distribution on SCC initiation. The following results were obtained. (1) In this SCC test, it was found that only micro cracks whose depths were smaller than 50um were observed until 200 hours and cracks whose depths w...
英字タイトル:
Evaluation of stress and plastic strain distribution on SCC initiation test piecewith surface work hardened layer

An infrared thermography NDE facility which is utilized in the acceptance test of ITER d ivertor components has been developed in JAEA. This NDE facility can inspect the integri ty of the bonding interface of the divertor components based on its surface temperature response by means of switching of hot (95 deg C)/cold (5 deg C) water. The advantages of this facility are 1) to have active coolant purging system which enables rapid temperatu re change and 2) to inspect the surface and the both side walls of...
英字タイトル:
Development of a non destructive evaluation system using infrared images for divertor on nuclearfusion experiment reactor

In this study, we propose a novel EMAT-ECT multi sensor aiming at advanced structural health monitoring. For the purpose, proto-type EMAT-ECT multi-sensor was developed and their functions both as ECT and EMAT prove were evaluated. Experimental results of pulse ECT using the EMAT-ECT multi-sensor showed that the pr oposed sensor has a capability of detection and sizing of flaws. Experimental results of EMAT evaluation using the EMAT-ECT multi-sensor showed that ultrasoni c wave was transmitted by EMAT-ECT ...
英字タイトル:
Development of novel EMAT-ECT multi-sensor and verification of its feasibility