SiC Ð Æ

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1 1» Vol. No.1 1 Ï Ã Journal of Chinese Society for Corrosion and Protection Feb. 1 - P91 P9 Ç Ì Ä»Å± Æ È Å : 1 ¾Á Î Ï 1 (1. º Òº Æ Á Ý º Ó 611;. ÆÈ Á ) X XRD«- ÞÍ SEM-EDX«P91 P9 Ç 5 /5 MPa 55 /5 MPa ß¾ ÂÄ Ú ¾ ݾ Áƽ ÂÄ ¼¼Ý Æͼ ÂÄ Fe O Æ˼ ÂÄ Fe O FeCr O ÆP9 ÇÚ ÂÄÕ ÌÀËÃǵ Ë Â Õ P91 P9 Ç ßÄ ÂÄ Ú Í¼ ÂÄ Fe O Úݱ«²Æ Fe O ÚÝÒ²±«ÆÇ ßØÖÆÍ ÕÅ µð Õ Æ : ß¾ ÂÄ Ú Ë ² : TG171 : A É : «1 1 5 ÆÌÀ Ò Ã» ¹Đ Õ Ó ÌÀÜ Ì Õ» ÝÉ É ½ µ ÞÉ Đ 6 É Å ½² Þ½² SCWRÅ ³ Þ ±Õ SCWR ß Ä 5% Ç ½  %Å Ü Ü Á Ô ÅÆ [1] SCWR ÅÆÆ ¹ Ý ÎÂÒÕ ½ ¹ Ì Á Ì ß±Ò ½ È SCWR ±Ñ [,] Ç Æ Þ½ «Æ SCWR ß Ã - F/MÅ ¼ Î Í̹ Ø ß ÍÒº ß Î Æ ÂÒÕ Ø «Ì¹ ± Æ ÞÉ ½Ü SCWR Ï Ð F/M Ï Ð Þ Klueh [] Ø Æ ÈÌÀÒÉ Æ P91 Ð ÞÉ Ò P9 Æ P91 Ë Þ É F/M Ï Ð Ô ÞÉ SCWR Ü [5] Æ ½ : ¼ : ¼ Í ÅßË À È 7CB98 ÜÔ ÍÊ : Æ É 197 Ôµ Å ³ ÅĐ Þ ¹ ÀÍÊ : xajttr@16.com Ð Õ Á Mo V Nb Ô Mo Đ ÁĐ V Nb ÆÃ Ë Ì Û¹» Ô MX ÊÁ ÏØÓ ÁĐ Æ P9 Æ W Ï Đ ÁĐ Á ½ Mo ÀØ Ni Ö Ô ½ Æ P9 Ni ¾ Æ.% ¹Ê Á¹ Ì Ü½ P9 Ô Ï Ç [6,7] Ø F/M Æ Ï Ã Þ½ «Æ À Áà Ż»Ü Ì» Fe Á Ê» Fe Á [8 1] ËØ P9 Æ Þ½ «Æ ÆÅ ½ ± ÆÒÉ ±Ø F/M Æ Þ½ «ÁÃÙÙ Ù Æ Ñ±Ø P91 P9 Æ 5 /5 MPa 55 /5 MPa Þ½ «ÁÃ Ü Ð ÁÃÙ Ê Â «P91 P9 Ë Þ Á 1 Ê ² mm mm 1.5 mm ± À SiC Ð Æ Æ 1 µm Ð µ Ü Æ Ç ² ÑÑ 1 min Ð Æ Å (SCW) Æ 5 /5 MPa 55 /5 MPa ÂÒÕ «h h 6 h 8 h 1 h

2 ¹«Table 1 Compositons of P91 and P9 (mass%) materials C Si Mn Cr Al Nb B Ni P P materials Cu Mo W V P S N Fe P bal. P bal. Table Test conditions for SCW exposure parameters conditions temperature / (5, 55)±5 pressure /MPa 5±.5 dissolved oxygen /µg kg 1 <1 (deaerated) water conductivity /µs cm 1.1 ph test time /h neutrality (RT) 1 sampling period/h 1,, 6, 8, 1 ººÐ Å«± Î (SEM) Ì EDXÅ ÁÃ Û Ü µ X «ß «XRDÅ Æ Áà РÆ.1 à ³ µ ± P91 P9 Æ 5 /5 MPa Þ½ «É Î Öß Ê 1 Î weight gain /mg dm - P91 P n=.8 n= time /h Fig.1 Weight gain as a function of exposure time obtained from the samples exposed to SCW at 5 6 and 5 MPa. W = k p t n (1) k p = k exp( Q/RT) () W ± É Q ÈÁÌ k Á º T Ô n º Å Î Ï P91 P9 º.7.8 Æ 5 Õ Áѹ P9 «P91. à º P91 ± Æ 5 /5 MPa Þ½ «1 h ÁÃÛ Ø Áû»Ü Ì» ÁÃÔ 8 µm Ê» ÁÃÔ 6 µm Ê» ÁÃØÌ» Áà (Ê a) P9 ± Æ 55 /5 MPa Þ½ «1 h Á ÃÛ Ê aå Ù P9 ± Áó»»Ü Ì» ÁÃÔ 1 µm Ê» Áà Ô 8 µm Ì Æ P9 Ë ÊÙĐ ÁÃ Ô Æ ½Ï Ê ÁÔ Æ Ô ÔÐ Ó ÁÃ Ë Ö É Ô concentration /mass% (b) distance / m Fe Cr O Fig. Cross-sectional SEM image of P91 after exposure to supercritical water at 5 /5 MPa for 1 h (a) and (b) the corresponding Fe, Cr and O composition profile across the oxide thickness

3 _ : L7H - A#H P91 < P9 O79{b D#JLv k > "IKa[E6 )?!'y T" 8 P91 ; P9 Ta jx1 R b, R b t e + T/ " I K Fe _ Cr R / " I K a 6 = < % x E 6 " 8 =?" [ l ; - < % * Cr t"[l;- > Fe t"[l;- 1G Cr Fe Cr S Fe [6 tt/ " I K a 6 a [ w.?" 6 ; Cr R / " I K? GP k"ik[} ; - P9 [*~Æ X { j R IR a - WFK! Fe O ;i Cr " I/[ ;ra " I K/}*z E [ " FeCr O [ x> XRD ; SEM-EDX j Fe ["Ih?(fk ~x" WT/ ; - w kt/ " I K ; R / " I K [} ; ;> Fe O } T/"IK Fe _ Cr 1G T/"IK[FK!. K. - $E Fe O } R / " I K 6 Fe Cr ; O [ Fe O P91 ; P9 N 5 /5 MPa 6 8 z1 a ; FeCr O } x1? e > w Y}e (P jc[!e C R 5, R 6 t e+!e"ik; L[ p,s[ueg, ; " 1 d [11 1] [1] 1 concentration /mass% (b) 8 6 Fe Cr O distance / m Fig. Cross-sectional SEM image of P9 after exposure to supercritical water at 55 /5 MPa for 1 h (a) and (b) the corresponding Fe, Cr and O composition profile across the oxide thickness Fe O /FeCr O intensity /a.u. -Fe the corrosion product of P91 after exposure Fig. X-ray pattern obtained from the surface of P9 after exposure to 55 Fig.5 SEM images of the surface morphology of /5 MPa for 1 h. to supercritical water at 5, 5 MPa for (a) h, (b) 6 h and (c) 8 h.

4 ¹«Fig.6 SEM images of the surface morphology of the corrosion product of P9 after exposure to supercritical water at 5, 5 MPa for (a) h, (b) 6 h and (c) 8 h. Áà ÐÐ Áà ٠¼ «Áà ÂÆǾ Ü ¼ ÁÃÛ Ê Ê Å Á à ٠̻ Áà Fe O ÃË ÐÆ SCW «ÏÏÌ Æ Áà ½Ï Áà à Fe O ÙÜ Å ± «O Neill [15] à Fe O Ü Ê 7 Æ Õ Fig.7 Schematic illustration of the crystal structure of magnetite Fe O, where large light balls denote oxygen, small black and gray balls denote iron. The small black and gray balls occupy the octahedral and tetrahedral site, respectively. Ü Fe + Ì«Fe + Fe + Ì«Ô Ã ÐÓÖ Ú Ü Fe + ØÉ Fe + Æ Ã ĐÁ Fe + Fe + ÎÌ«Barry [16] Æ Þ Õ Ã Ü ± ÝÂÅ (Fe +, Fe + ) (Fe +, Fe +,Va) (Fe +,Va)(O ), (Fe +,Fe + ) Ã³Ý (Fe +, Fe +,Va) Ã³Ý (Fe +,Va) à ³Ý ³Ý Ó Ý Ã Æ Đ Õ Á ¹ Á (Fe +,Fe + )(Fe +, Fe + ) (O ) Æ Þ Õ Áà ³ÝÁË Áà ÁÃ Ë ½Ü º Ã Đ Ã Ü Á (Fe +,Fe + ) (Fe +, Fe +,Va) (Fe +,Va)(O ), (Fe +,Fe + ) (Fe +, Fe +,Va) (Va)(O ) à à ÙÜ Ñ ± Å Fe + Ó Ý Ã ÙÜѱ Å Ì Ã ÔÄÏ Ô 1ÅP91 P9 Æ 5 /5 MPa 55 /5 MPa Þ½ «Áû»Ü Ì» Áà Fe Cr à РFe O Ê» Áà Fe O Ð FeCr O P9 ÁÃ Æ ÙĐ ÁÃÔ Ë ÊÂÆ Ê ÁÔ ÅP91 P9 Æ Þà «Áà ٠̻ Áà à Fe O Å ÙÜ Å ± à ÙÜѱ Å Ì Ã ÔÄÏ Ô

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