Zn-Al Alloy Coated Steel Sheet
Transcript of Zn-Al Alloy Coated Steel Sheet
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Zn-Al Alloy Coated Steel Sheet
Kazuhiro TANG, Joji OKA, Minoru KAMADA, Misao OBU
Effect of increasing Al content of Zn coating bath on the durability of hot dip galvanizing steel sheet is studied. After investigating the corrosion mechanism, easiness of coating operation and economical merit of Zn-Al coating, Zn-4.5% Al-0.1% Mg alloy coated steel sheet has been developed. It has an excellent corrosion performance in various atmosphere and a superior coating adherence to the conventional galvanized steel sheet. On the basis of long period exposure test results, it is expected to decelerate the development of red rust on the painted sheet. Therefore, it has a bright future as a resource-savable coated steel sheet.
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Fig. 1 Relation between Al content and weight loss on outdoor exposure test
(Tobata, industrial environment)
ïŒ1 æ° æ¥æ¬è£œé(æ ª)å «å¹¡è£œéæ(ã805 åä¹ å·åžå «å¹¡æ±åº
æå 1-1-1)
Yawata Works, Nippon Steel Corp. (1-1, Edami-tsu-1 chome,Yawata-Higashi-ku, Kitakyusyu-shi 805)
ïŒ2 æ° æ¥æ¬è£œé(æ ª)åºç€ç 究æ(ã211 å·åŽåžäžååºäº ç°
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Fundamental Research Labo., Nippon Steel Corp.(1618, Ida, Nakahara-ku, Kawasaki-shi 211)
ïŒ3 æ° æ¥æ¬è£œé(æ ª)çç£æè¡ç 究æ(ã805 åä¹ å·åžå «å¹¡
æ±åºæå 1-1-1)Process Technology R & D Labo., Nippon Steel Corp. (1-1, Edamitsu-1 chome, Yawata-Higashi-ku, Kitakyusyu-shi 805)
ïŒ4 æ° æ¥æ¬ 補 é(æ ª)æ¬ç€Ÿ(ã100 æ±äº¬ éœ å 代 ç° åºå€§ æ çº2-
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Head Office, Nippon Steel Corp. (6-3, Otemachi-2chome, Chiyoda-ku, Tokyo 100)
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Vol.33, No.10, 1982 Zn-Alå é ã 㣠ã éŒ æ¿ 517
Table 1 Sample preparation
Table 2 Sample preparation
Fig. 2 Effect of Al content on conversion
coating weight.
Fig. 3 Effect of Al content on the corrosion re-sistance of bended paint layer (Salt spray test 240hrs, 2mmÏ bend).
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æž ãããæŽã«Alé ã15%ã« å¢å ã ããš,é ã«è é£æžé
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è㯠ãé¢ ç¶æ³ ã§è©äŸ¡ ã ãçµæ ãå³3㫠瀺 ã ã,Alã
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ç¶ çºéãæå¶ ã,ã ã®éã3ïœ5%㧠ã»ãŒ 飜 å ã ã)
Al㫠察 ããŠ5%ã®Siã æ·»å ããŠãµã³ãã«ãäœæ ããããª
ã,ã ã®Alå¢ å€§ã« ããå éå±€æé·ã¯,ã ã£ãé,浞 ã
ãããŒã«çã®ãã£ãæ©æ¢°çŽ æã®æº¶é£ã«ã€ãªããçŸè±¡ã§ ã
ã ã,é«Al济 äœæ¥ã§ã¯,ã ã®ç¹ ã«å·¥å€«ãèŠã ããã®ãš
èã ãããã
ä»¥äž ã®å®éšçµ æãç·åçã«å€æ ããŠ,äº é 济 äž ãž ã®
Alæ·» å éã¯4.5%çš åºŠã«ã ãããšãåºæ¬çã«æ±ºå® ããã
2-2 ä»å çŽ ã®åœ±é¿
溶èäºéãã£ãã§ã¯,åŸ æ¥,济 äžã«åé å±€æå¶ ã®ãã
ã®Alã® ä»,Pb, Cdã æ·»å ããŠã ããPb, Cdã® äž»ãªæ·»å
ç®ç 㯠㹠ã ã³ã° ã«åœ¢ æ 㧠ã ãã,é« é ã 㣠ãæ ã® ã 㣠ã
é¢ ã®å¹³ æ» æ§,é£ ç¶ æ§ ã®ç¢º ä¿ ã® ãã 㧠ãã ãã è è ãã®ç
究 ã« ã ã ㊠ã ãã®ç¹ ã è æ ® ã,Pb, Cdã® ä»,Sn, Fe(å¿
ã æ·· å ¥ ã ã)ã,Zn-Alå é ã 㣠ã ã®äœ æ¥ æ§,æ§ èœ ã« å
㌠ã 圱 é¿ ã調 æ» ãã ã
åº æ¬ æµŽ ãšãª ãZn-4.5%Al济 ã¯,JIS H2107ç¹ çš® äº é å°
é çž åœå ãš,JIS H2102ç¹1çš® ã¢ã« ãã ㊠ã å° é 㧠調æŽ
ã,Pbã0.005, 0.01, 0.02, 0.03, 0.05, 0.10, 0.20
0.50%, Snã0.001, 0.01, 0.02, 0.05%, Cdã0.005
0.01, 0.03, 0.05%,å ã³Feã0.01, 0.03, 0.05, 0.1,
0.2%,å ã åç¬ ã§æ·» å ã㊠ã 㣠ã ãè¡ ãª ã£ã ã ã ã®çµ
æ,㩠〠ã³é 床 ã5ïœ10m/å çš åºŠ ã®ã 〠ã ã ã㩠〠ã³
Table 3 Effect of Al content on the properties after painting
1) * Cracking
2) Treating condition
phosphate treating ãBt 3305-Pn 62,70â, 9sec.ã
chromium treating ãBt 712, 55â, 10sec.ã
3) â Excellent, â Good, â³ Fair, Ã Bad
Fig. 4 Effect of Al content on anodic polarization in 3% NaCl solution (potentiostatic method).
-80-
Vol.33, No.10, 1982 Zn-Alå é ã 㣠ãéŒ æ¿ 519
Fig. 5 Effect of Pb and Sn content in bath on
coating adhesion.
Fig. 6 Effect of Mg content on coating
adhesion.
Fig. 7 Coating adhesion on Si containing
substrate.
Fig. 8 Outdoor exposure test results of galvanized,
and Zn-Al-Mg coated steel sheets in several
places.
ã§ã¯,ã ããã®å Žå ãåäžã§è¯å¥œ ãªã ã£ãé¢ ã åŸ ãã
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ããç²çè é£ ã®æç¡ãäžå¿ã«èª¿æ» ãããè©Šéšæ³ã¯,ã ã£
ãéŒæ¿ ã®ç¹åŸŽãèæ ® ã,70â, 100%湿 床é°å²æ°24hæŸ
眮åŸã« ããŒã«ã€ ã³ã 㯠ãè©Šéš ãè¡ ã,æŽ ã«ã㌠ãã³ã°ã
è¡ ãªã£ãŠ,ã ã€ãå±€ ã®ã¯ ãé¢ç¶æ ã§å€å®ããæ¹æ³ãæ¡çš
ããã
Pb, Sn, Cd, Feã® ãã¡,Cdã¯0.05%以 äž,Fe㯠ã ã£
ã济äžã«ååš ãåŸ ã0.2%以 äž(ã ãä»¥äž ã¯ ããã¹ ãšã
ãŠæåºã ã)㧠ããã°,æ§ èœäžã«äœ ãæª åœ±é¿ ãå㌠ããª
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ã« ãã£ãŠã¯ã 㪠ãã ã€ãå±€ ã®ã¯ ãé¢ãèª ã ããããå³5
ã«ãã®çµæ ã瀺ãã,Pbã¯0.1%, Snã¯0.02%以 äžã«
ã ãå¿ èŠã®ããããšãæ ãã«ãª ã£ãã
Pb, Snã® ååšã,ç² çè é£ã« ãã,å¯ çæ§å£åã ã
ã ãã ããšã¯,è¡š é¢åŠçéŒæ¿ ã®ç¹æ§äž,確 å®ã«è§£æ±ºãã¹
ãéèŠãªåé¡ ã§ã ãã ãã®ããã«ã¯,Pb,Sné ãå ã å¶
éãã ããšãæå¹ã§ããããšã¯å ã«è¿°ã¹ãã,補 åã®äœ¿
çšæ¡ä»¶,補 é äžã®æ¡ä»¶å€åãèããã°,æŽ ã«å¥ã®æ段ã
çµåãã ãŠ,å® å šãªå¯Ÿçãè¬ ããããšãåŸçã§ã ãã ã
ãã§,æŽ ã«å¥ ã®å çŽ ã人çºçã«æ·»å ã,Pb,Snã® åœ±é¿ ã
ææ¶ãæ¹æ³ ã®æ€èšãè¡ ãªã£ããæ·»å å çŽ ãšããŠ,Mg, Ti,
Cu, Beã æ€èš ããçµæ,å¹ æ,æ·» å æ³,管 ç,䟡 æ Œç
ã§Mgã æ ãå®çšçã§ã ãããšãèŠ åº ããã幟å€ã®å®éš
ãå®æœ ã,Pb, Snã® æªåœ±é¿ãææ¶ãMgã® é ãš,Pb, Sn
é ã®é¢ä¿ ãå³6ã® åŠ ãæ ããã« ããã
以äž,济 æåã®æ€èš ãç¶ããçµæ,Zn-Alç³» åéãã€
ãã®åºæ¬çµæã,Zn-4.5%Al-0.1%Mg㫠眮 ã,çŸ å Žè£œ
é ã©ã€ã³å®éšãžç§»è¡ ããã
2-3 å®ã©ã€ã³ãã£ãäœæ¥ãšãã®æ§èœ
çŸå ŽèŠæš¡ã® ã©ã€ ã³ã§å®éã«Zn-4.5% Al-0.1% Mgã®
åéã ã€ãæ¿ãè©Š äœ ã,çŸ å Žäœæ¥æ§,æ§ èœ ãæ€èš ããã
ã ã£ãäœæ¥ã¯è£ 眮ææ,æ æ¥æ¡ä»¶ ã«è¥å¹² ã®å·¥å€«ãæœ ã
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ã ãã
2-3-1 ã ã€ãå±€ ã®å å·¥æ§
Zn-Al-Mgå éã ã€ãéŒæ¿ ã¯,ã ã€ãä»çé ã100ïœ
150g/m2ã® å Žå,ã ã¬ã¹æå æã®ãã€ãå¯çæ§ã極ããŠ
åªã ãŠãããå®éšå®€çã«å¹Ÿã€ãã®ã ã¬ã¹æåãè¡ãªã£ã
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èŒ ããçµæ ãå³9㫠瀺ãã
å³8,å³9ã ã,Zn-Al-Mgå éãã£ãéŒæ¿ã¯,å äž
ä»çé ã®äºé ãã£ãéŒæ¿ ã ãçžåœé·æéã®å¯¿åœå»¶é·ãæ
åŸ ã§ãã ããšããã ãã
次 ã«,é« æž©å€æ¹¿é°å²æ°ã§ã®äœ¿çšãæ³å® ãã湿 æ°æ§œè é£
ä¿ é²è©Šéšçµæãå³10ã«,㟠ã,代 è¡šçãªè é£ä¿ é²è©Šéš ã§
ããå¡©æ°ŽåŽé§è©Šéšã«æŒ ããè é£é床ãå³11㫠瀺ãã
ãããã®è©Šéšã«ãã㊠ã,Zn-Al-Mgå é ãã£ãéŒæ¿
ã¯,åŸ æ¥ã®äºéãã£ãéŒæ¿ ã ãæ Œæ®µ ãšåªããèé£æ§ã瀺
ããŠã ã,å® çšäž,çž åœæå¹ãªç¹æ§ ãçºæ®ã ããã® ãšæ
ãã ãã
2-3-3 å¡è£ åŸ ã®èé£æ§
Zn-Al-Mgå éã ã£ãéŒæ¿ã®å¡è£ åŸèé£æ§ã¯,ä¿ é²è©Š
éš,äŸ ãã°å¡©æ°ŽåŽé§è©Šéšã«ãããå¡èã¹ ã¯ã© ããéš ã®ã
㯠ã¬å¹ ãåŸæ¥ ã®äºéãã£ã ã ãçž åœåªã㊠ããããšã確
èªã§ ããã,å® éã«å»ºæ,å± å€èšçœ®ç©çã«äœ¿çšãã ãå Ž
Fig. 9 Relation between coating weight and
years to first rust (Outdoor exposure test in industrial environment).
Fig. 10 Corrosion performance of galvanized, and
Zn-Al-Mg coated steel sheet on Humidity
cabinet test.
Fig. 11 Corrosion performance of galvanized, and
Zn-Al-Mg coated steel sheets on salt
spray test.
Fig. 12 Appearance of painted specimens after 5
years' exposure in Tobata
(Acrylic paint, 30ÎŒm)
-82-
Vol.33, No.10, 1982 Zn-Alå é ã 㣠ãéŒ æ¿ 521
å ã®æåã¯,é· æå±å€ æŽé²è©Šéšã§ç¢ºèªãã¹ ãã§ãã ãã
ãŸã,å® çšéã§ã¯åœç¶,æœ å·¥æã®æåå å·¥éš,å æ± ãçµ
éš,䜿 çšäžã®çµ 〠ãéš ãªã©ã®è¡šé¢æå·éšã ã,åª å çã«
å£åãé²è¡ã ããšæãã ããèè ãã¯,ã 㪠ãé·æ éã«
äº ãå±å€æŽé²è©Šéš ãå®æœäž ã§ã ãã,5ïœ6幎 çµéã ã
ãšå®çšäžåé¡ ãšãªãèµ€é¹ ã®çºçã«ææå·®ãèªã ãã ãã
ãã§ã ãã5幎 éã®æŽé²ã« ããã¹ ã¯ã©ããéšã®å€å ã®äž
äŸãå³12㫠瀺ã ã,ã¹ ã¯ã© ããéšã ãã®èµ€éã®æ¡ ã ãã¯
Zn-Al-Mgå éãã£ãéŒæ¿ ã®æ¹ã,å° ããããšãæ ãã
ã§ããã
3. è å¯
äºé ãã£ã济 äžã«Alã® æ·»å é ãå¢å ããŠãã£ãå Žå,
éåžž ã®äºéã ã£ãéŒ æ¿ ã ãè¡šé¢ ã®å極ã倧 ã ã㪠ã,è
é£æ§ãå€§å¹ ã«åäžã ã ããšãè¿°ã¹ãããã®çŸè±¡ã«ã€ããŠ
æŽã«æ€èšãé²ããçµæ,è é£çæç©ç®èã« ããè é£ æå¶
ãšã ãèãæ¹ã® ãšã ãããšããã ã£ããåå ã7),10)ã¯ã¢
ã« ãããŠã ç² æ«ãè€å ããZn-Alã ã£ãã®é²é£æ©æ§ ã次
ã®ã ãã«èª¬æ ããŠãããAl㯠æ¬æ¥,å± éš ã«ãœ-ã ãš ã
ãŠå ãã¯ãã§ã ã ã,AIã® è¡šé¢ã¯é»æ°äŒ å°åºŠãå° ãã
é žåç®èã§èŠãã㊠ãããã,é ž çŽ éå åå¿ ã æ å¶ ã
ã,㢠ã㌠ãåå¿ã§ã ãZn㮠溶åºé床ã¯,ã ãã ãå°
ã ã㪠ãããšåæã«è é£çæç©ã§ããZné ž åç©ã¯,Al
ç²æ«ã«ä¿æãã ãŠè¡šé¢è¢«èŠå±€ã圢æ ã,æ¡ æ£æµæã倧 ã
ã㪠ãã®ã§,è é£ãæå¶ãããŠãããšããŠãããèè ã
ã¯æŽã« äžæ©é²ãã§,è é£ çæç©ãäœæ èé£æ§ã«å¹æãã
ãããæ€èš ããã
Znã® è é£åå¿ã¯æ¬¡ã®ã ãã«è¡šã ãããã
ã¢ã㌠ãåå¿:Zn+2H2OâZn(oH)2+2H++2eâŠ(1)
Zn(OH)2âZnO+1/2H20âŠâŠâŠ(2)
ã«ãœãŒ ãåå¿:1/2O2+H2O+2eâ20H-âŠâŠâŠ(3)
Zn(OH)2㯠é»æ°äŒ å°åºŠ ãå° ããã®ã§,ã ã®ç®èãZn
ã®è¡šé¢ã«åœ¢æããããš,Znè¡š é¢ ã§ã®é ž çŽ éå åå¿ ã§ã
ã(3)åŒãæå¶ãããšããããŠã ãã ãã ã,Znå ç¬ ã
ã£ãã®å Žåã«ã¯Zn(OH)2ã¯,(2)ã® åå¿ã§nå åå°äœ ã§
Fig. 13 Electron micrographs of Fe-Al-Zn alloy lager.
ã ãZnOã« å€åã ãã®ã§,é ž çŽ éå åå¿æå¶å¹æã¯å°
ããã岡 ç°ã11)ã¯,Znã® å䌌㵠ããçšã,Zn(OH)2äž
ã«ããçš® ã®éå±ãæ·»å ã ããš,(2)ã® åå¿ãæå¶ ãã ãã
ãšãèŠåº ããŠã ãã
(2)ã®åå¿ãæå¶ ãããã°,Zn(OH)2ç® èã« ã ã(3)ã®
åå¿ ãæå¶ ã ã ã ã® ã§,ã ã®å¯Ÿå¿åå¿ ãšããŠ,(1)ã® å
å¿,ã ãªãã¡,è é£ãæ å¶ãã ãããšã« ãªããå²¡ç° ãã®
䞻匵ã«åŸã,Al, Mgã æ·»å ããŠå䌌㵠ããäœ ã,Xç·
åæ ãè¡ãª ã£ãçµæ,Znå ç¬ã®å䌌 ãµ ããZnOã ããª
ã£ãŠããã®ã«å¯Ÿ ã,Al,Mgã æ·»å ããŠäœ ã£ã ãã®ã¯,
Zn(OH)2ã ããªã£ãŠã ãããšããã ã,Al, Mgã¯Zn
(OH)2ã å®å®å ãã ãæåã®ããããšãå€ æ ãããæŽ
ã«,Zn-Al-Mgå éãã£ãéŒ éªã®å¡©æ°ŽåŽé§è©Šéš42,72æ
éåŸã®è é£çæç©ãXç· åæ ã§èª¿ã¹ãããã®çµæ,ç æ
ã ããµ ãã¯,ZnCl2ã»4Zn(OH)2㧠ã ã,ZnOã« å€ã ã
ã« ããããšãèªã ããã12)ã
ã ãªã ã¡,Zn-Al-Mgå éãã£ãéŒæ¿ã®é²é£æ©æ§ ãšã
ãŠ,è é£ ã®åæã«çæ ããè é£ç®è ã¯,ã ã£ãè¡šé¢ãèŠ
ãã,Al, Mg㮠圹å²ã§è é£çæ ç©ãé»å°åºŠ ã®å° ããZn
(OH)2㪠ããã«ä¿æ ãã,é ž çŽ é å åå¿ãæå¶ ããã ã
ã®ãšèã ãã ãã
äžæ¹,Zn-Al-Mgå éãã£ãéŒæ¿ã¯,åª ããã ã£ãå¯
çæ§ã瀺ããAlã0.1ïœ0.2%å« ãéåžžã®æº¶èäºé ãã£ã
ã§ã¯,ã 㣠ãæ,çæã ãåéå±€ã¯,å° éåŽã«Fe2Al513),
ãããã¯,Fe-Al-Znäž å åéå±€14)ã圢æ ãã,æŽ ã« ã
ã®å€åŽã« ãã ãã« ãã£ãŠéãæ å¶ ããã1ÎŒmå åŸ ã®
Fe-Znå éå±€ãçæããã ããã«å¯Ÿ ã,Zn-Al-Mgå é
ã ã£ãã§ã¯,é» æ°ååŠçæ¹æ³ã§,ã ã£ãå±€,å éå±€ãã¯
ãé¢ ããŠè¡ ããš,Fe-Znå éå±€ã¯ã»ãšã ã©èªã ããã,
ãŸãFe-Al-Znå éå±€ã¯,å® é»æµé»è§£ã«ãããŠéåžž ã®äº
éã ã£ãéŒæ¿ ãšåæ§ ãªé»æµ-é» äœæ²ç·ã瀺 ã,ãã®å ãã
èããå³13ã« äž¡è ã®Fe-Al-Znå éå±€ã®å€èŠ³ ãæ¯èŒ ããŠç€º
ãã,Zn-Al-Mgå éã ã£ãã®å Žåã®ã¡å¯ ãããã ãã
ãã® ãããªåéç¹æ§ ã§ã ãZn-Al-Mgå éã ã£ãéŒæ¿
ã¯,ã ã¬ã¹å å·¥çã« ãã£ãŠ,ã ã£ãå±€ã®ã¯ ãé¢ãèµ· ã ã
é£ ãã
ãŸã,ã ã£ãå¯çæ§ ç¢ºä¿ã«é£ç¹ã®ã ãSi
ãå«ãçŽ æ㧠ã,å¥ å š ãªFe-Znå éå±€ãç
æã ããã,è¯ å¥œãªã ã£ãå¯çæ§ ãç¢ºä¿ ã
åŸ ããã® ãšèããã ãã
ãã€ã ã£ã¹ ãå é(Zn-Al, Zn-Al-Mg
åé)ã ãã®æ å ± ã§äºèŠãããç²çè é£15)
ã¯ã ã£ãã®å Ž å,é© æ£ãªæ¡ä»¶ ã§ã ã£ãããª
ããšçµæã« ãããã£ãå¯çæ§å£å,è é£é
å¢å€§ ãšã ã圢 ã§çŸãããã ãã ã ã® å Ž å
ã,ç² çã§ã®è é£é²è¡ ãš,ã ãã« ããã ã£
ãå±€ã®ãã匱åçŸè±¡ ã§ãã ããã ã£ãæ¿ ã®
å Žå,ã ã€ã ã£ã¹ ãåé ãšç° 㪠ãç¹ ã¯,
-83-
522 ç 究 éå±è¡šé¢æè¡
Fe, Cdã® ååšãå®çšäž,å é¡ã«ãª ããªãç¹ ã§ã ããç¹ã«
Feã® ååš ãå質ã«åœ±é¿ ããªãããšã¯,ã ã£ãæ,Feã®
æ··å ¥ãé¿ã ãããªãã ãã«,å·¥ æ¥çã«æ矩ã倧 ãããã
ã£ããšãã€ã ã£ã¹ ãéã®ãã ãã®çžéç¹ã¯,é« é ã§å·åŽ
ãããååºçµç¹ã§ãããã£ãå±€ç¹æã® ãã®ãš æ ã ã ã
ã,å è¿°åéå±€ ã®çµæ,Mgã® æ åãšãšãã«,ä» åŸè§£æ
ããŠã ãå¿ èŠããããšæãã ãã
4. çµ èš
溶èäºéã㣠ãéŒæ¿ ã®é·å¯¿åœåãç ã£ãŠ,ã ã£ã济äž
ã®Alå« æ éãå¢å ãããç 究ãè¡ãª ã£ãçµæ,é² é£å¹
æ,ã ã£ãäœæ¥ã®å®¹æ ã,çµ æžæ§ãªã©ãç·å ç ã« è© äŸ¡
ã,Zn-4.5%Al-0.1%Mgã åºæ¬æµŽæå ãšã ãZn-Al-
Mgå éã ã£ãéŒ æ¿ãéçº ããã
ãã®ã ã£ãéŒæ¿ã¯,裞 ã®èé£æ§ãçš® ã ã®è é£é°å²æ°ã§
é åžžã«åªããŠããã»ã,ã ã£ãå¯çæ§ ãéåžž ã®äºéãã£
ãéŒæ¿ ã ãè¯å¥œ ã§ããã ãŸã,å¡ è£ åŸã®æ§èœ ã,é· ææŽ
é²è©Šéš ã®çµæ,èµ€ é ã®çºçãé ãããšãæåŸ ã§ ã ã ãª
ã©,ä» åŸ,ç è³æºååéã ã£ãéŒæ¿ ãšããŠææã§ã ããš
èã ãã ãã (1982-6-23å ç)
æ ç®
1) W.C. Sievert, et al.; Method of Hot Dip Coat-
ing with a Zinc Base Alloy Containing Magnesium
and the Resulting Product, USP 3505042(1970)
2) H.H. Lee, et al.; Al-Mg-Zn Alloy Coated Ferr-
ous Metal Sheet, USP 3505043(1970)
3) W.P. Roe, et al.; Galvanized Ferrous Articles,
USP 3320040 (1967)
4) H.H. Lee; Zn-Al Hot Dip Coated Ferrous Sheet,
USP 4029478 (1977)
5) A.R. Borzillo, et al.;被 èŠ é 補 å,ç¹ å ¬ æ 46-7161
6) J. Pelerin, et al.; GALFAN-溶 è äº é ã 㣠ãçš
å é ãšæ è¡,é ãšäº é,第106å· ã3ã (1982)
7) æš æ è,å å æ¬ ä¹ ,å ç°ä¿ äž;é« è é£ æ§Zn-Alè€
å é» æ° ã 㣠ãéŒ æ¿ ã® é çº,å· åŽè£œ é æ å ± 12, ã4ã 65
(1980)
8) J.C. Zoccola, et al.; Atmospheric Corrosion Be-havior of Zn-Al Alloy Coated Steel, Paper of 1976
ASTM Symposium on Atmospheric Corrosion (19
76, 5æ)
9) H.R. Thresh, et al.; Properties of Molten Zinc
and Zinc Alloys Part II; Viscosity, Physical Met-
allurgy Division Internal Report PM-R-64-27 (by
ILZRO) (1965, 10æ)
10) å å æ¬ ä¹ ,æš æ è,å ç° ä¿ äž;é« è é£æ§ äº é-ã¢
ã« ãã ㊠ã è€ å é» æ° ã 㣠ãéŒ æ¿ ã« é¢ ã ã ç 究 ,é ãš
éŒ, 66 ã7ã, 779 (1980)
11) H. Okada, K. Yamamoto, I. Ito; Proceeding In-
ternational Congress on Metallic Corrosion , p. 275
(1972)12) 岡 è£ äº,æ éç§ æ¬¡é,é« æ æ¿ å¿,å±± æ¬ äž é;é ãš
éŒ, 68 ã2ã A57 (1982)
13) D. Horstmann; The Influence of Steel and of
Galvanizing Conditions on the Properties of Gal-
vanized Steel and Strip, Proc. 7th Inter. Conf. on
Hot Dip Galvanizing, p. 146 (1967)
14) A.R.P. Ghuman, et al.; Reaction Mechanisms for
the Coatings Formed During the Hot dipping of
Iron in 0 to 10pct Al-Zn Baths at 450° to 700â,
Met. Trans. 2, 2903 (1971)
15) æ¥æ¬ é äº é é èŠ ç 究 äŒ ç·š;äº é ã ã³ ãã ã ã¯,p 112
(1977, (æ ª)æ¥åå·¥ æ¥ æ° è瀟)
-84-