Study on Pb-Bi Corrosion of Structural and Fuel Cladding Materials for Nuclear Applications (2); Part II. Exposure of Weld P122 in Oxygen Containing Flowing LBE at 550C for 5,000h

原子炉構造材料及び燃料材料の鉛ビスマス中腐食に関する研究,2; 第2報P122溶接継手の550C酸素濃度制御流動鉛ビスマス中における5000h浸漬試験結果

Schroer, C.*; Voss, Z.*; Wedemeyer, O.*; Novotny, J.*; Konys, J.*; Heinzel, A.*; Weisenburger, A.*; Mller, G.*; 古川 智弘  ; 青砥 紀身 

Schroer, C.*; Voss, Z.*; Wedemeyer, O.*; Novotny, J.*; Konys, J.*; Heinzel, A.*; Weisenburger, A.*; Mller, G.*; Furukawa, Tomohiro; Aoto, Kazumi

本報告書は、P122(12Cr-2W)鋼TIG溶接継手の550C酸素濃度制御流動鉛ビスマス(LBE)中における800h、2,000hおよび5,000hの腐食試験結果についてまとめたものである。LBE流速および溶存酸素濃度は、それぞれ2m/s、510 mass-% (a = 10)である。鋼材の腐食に及ぼすアルミニウムによる表面改質(GESA処理)効果についても評価を実施した。溶接継手の腐食挙動は、定性的にも定量的にもの熱処理が行われた母材のそれと同等であった。ごく一部に母材のそれとは異なる結果が得られたが、供試材の問題であると考えられた。溶接部のGESA処理部分には、高温酸化、液体金属腐食ともに観察されず、良好な耐食性が観察された。

This report summarises the results of exposure experiments on the behaviour of 12Cr-2W steel P122 joined by multi-run TIG welding in oxygen-containing flowing lead-bismuth eutectic (LBE) at 550C for nominally 800, 2000 and 5000 h. The flow velocity of the LBE and the mean oxygen content were 2 m/s and 510-7 mass-% (aPbO = 10-3), respectively. The influence of surface-alloying with aluminium (GESA-treatment) was also investigated in an exposure experiment for nominally 5000 h. The behaviour of the welded joint is generally comparable to that of P122 (after the standard heat-treatment), both qualitatively and quantitatively. Only few exceptions were observed which probably result from local peculiarities of the specific sample material. After surface alloying with aluminium, no significant oxidation and no liquid metal corrosion occurred in the centre of the specimens (including the weld seam), where the desired high quality of the aluminised layer was achieved.