原材及經熱浸鍍鋁-矽塗層430不銹鋼，分別於750℃與850℃單純空氣及氯化鈉蒸汽(500、990 vppm)之流動混合氣氛進行高溫腐蝕實驗，探討合金鋁化鍍層之鬚晶成長及高溫腐蝕機制。實驗結果顯示，於500 vppm氯化鈉蒸汽高溫腐蝕，430原材生成多孔性氧化鉻皮膜，無法抑制氯之侵蝕。持續供給的氯化鈉氣氛，會加速氧化鐵內離子擴散速度，使外側氧化鐵皮膜成長Fe2O3鬚晶；但於較高濃度之990 vppm氯化鈉蒸汽，卻無Fe2O3鬚晶成長。
熱浸鍍鋁矽430不銹鋼於高溫腐蝕初期，表面會形成一層緻密的氧化鋁皮膜。由於鋁和氯的相互作用，鍍層表面會出現Al2O3鬚晶。隨腐蝕時間的增加，鋁化鍍層失去保護性後，氯化/氧化之交替反應持續腐蝕合金底材，Fe2O3隆出於鍍層之上，表面亦成長Fe2O3鬚晶。
相較於850℃的腐蝕結果，於750℃之高溫腐蝕，表面可觀察到更細長的Fe2O3鬚晶。氧化物鬚晶的成長，與溫度、氣氛中氯化鈉濃度及氧化皮膜之晶體缺陷有關。

The mechanisms of whisker growth and high temperature corrosion of 430 stainless steels(430SS) with/without aluminum-silicon coated were studied at 750℃ and 850℃ in air/air-NaCl(g)(500, 990 vppm) atmosphere. The results showed that the porous Cr2O3 scale could not prevent corrosion in 500 vppm NaCl(g) atmosphere. The Fe2O3 whisker grew on the surface due to the accelerated diffusion of ions in the scale by the continuous supply of NaCl(g) atmosphere. There is no Fe2O3 whisker on the scale surface in the higher concentration of 990 vppm NaCl(g) atmosphere.
A compact alumina scale formed on the surface of coated 430SS after high temperature exposure. Due to the reaction of aluminum and chlorine as well as oxygen, Al2O3 whiskers grew on the surface of the coating. The cyclic chloridation/oxidation degraded the protection of the alumina scale and Fe2O3 grew from the defects of the alumina scale. In addition, the Fe2O3 whisker grew on the Fe2O3 scale.
Comparing with 850℃, the slender Fe2O3 whisker could be more frequently observed in the corrosion at 750℃. The growth of oxide whisker to depend on the temperature, concentration of NaCl(g) and crystal defects of scale.

1. George Y. Lai, "High-Temperature Corrosion of Engineering Alloys", ASM International, pp. 20-28 (1990).
2. J. M. Oh, "High Temperature Corrosion of Superalloys in an Envirionment Cantaining Both Oxygen and Chlorine", Metallurgical Transaction A (Physical Metallurgy and Materials Science), Vol.17A, pp. 1087 (1986).
3. A. Dang, G. A. Capuano, U. Bernabai, and F. Felli, "High-Temperature Oxidation and Thermal Cycling of Aluminum-Electroplated Stainless Steels", Oxidation of Metals, Vol.39, No.3/4, pp. 263-276 (1993).
4. W. Gao and G. Li, "The Development and Application of Hot-Dip Aluminum Coating", Heat Treatment of Metals, Vol.6, pp. 11-15 (1991).
5. H. Vogel, H.J. Kaesche and G Eggler, Parket Metallogr, Vol.22, pp. 162-173 (1985).
6. R. Bender and M. Schutze, "The role of alloying elements in commerical alloys for corrosion resistence in oxidizing-chloridizing atmospheres Part I: Literature evaluation and thermodynamic calculationx on phase stabilities", Materials and Corrosion, Vol.54, pp. 567 (2003).
7. J. Muller and M. Schierling, "Chemical vapor deposition of smooth α-Al2O3 films on nickel base superalloys as diffusion barriers", Surface and Coating Technology, Vol.120-121, pp. 16-21 (1999).
8. J. G. Smeggil and N. S. Bornstein, "The effect of NaCl(g) on the oxidation of NiAl", J. Electrochem. Soc., Vol.125, No.8, pp. 1284 (1978).
9. M. K. Hossain and S. R. J. Saunders, " Microstructural Study of the Influence of NaCl Vapor on the Oxidation of a Ni-Cr-Al Alloy at 850℃", Oxidation of Metals, Vol.12, pp. 1 (1978).
10. D. R. Stull and H. Prophet, "JANAF Thermochemical Table", Edward Arnold, London, NSRDSNBS37, pp. 31 (1983).
11. 李美栓，金屬的高溫腐蝕，北京冶金工業出版社，第78頁，北京，2001。.
12. 吳德樺，「熔湯鍛造法製造A356鋁合金－中碳鋼疊合材料」，國立台灣工業技術學院機械研究所碩士學位論文，台北，民國80年7月。
13. 張憲文，”熱浸覆蓋法(上)”，金屬表面技術雜誌，第85期，民國73年1月。
14. 洪舜立，「低碳鋼熱浸鍍鋁之研究」，國立台灣工業技術學院機械研究所碩士學位論文，台北，民國82年7月。
15. 林坤正，「鋁矽塗層於鐵基材熱循環之研究」，國立台灣工業技術學院機械研究所碩士學位論文，台北，民國84年7月。
16. 王朝正、劉勳洲，「310耐熱鋼之氯化鈉循環熱腐蝕」，防蝕工程，P105-119，1997。
17. 陳鵬交，430不銹鋼熱浸鍍鋁矽之高溫氧化，國立台灣科技大學機械研究所碩士學位論文，台北，民國93年7月。.
18. Higuchi, "Hot-Dip Aluminum Coated Steel Sheet Having Excellent Corrosion Resistance and Heat Resistance", United States Patent, pp. 489-493 (1990).
19. D.M. Dovey and A. Waluskit, "Continuous Dip Aluminising of Steel," Metallurgia", pp. 211-217 (1963).
20. F. Fitzer and J. Schlichting, "Coatings Containing Chromium, Aluminum, and Silicon for High Temperature Alloys", Oxidation of Metals, Vol. 3, No. 2, pp. 465-471 (1986).
21. S. Kobyashi and T. Yakou, "Control of intermetallic compound layers at interface between steel and Aluminum by diffusion-treatment", Materials Science and Engineering A361, Vol. A338, pp. 44-53 (2002).
22. E. Chang J. H. Sun, C. H. Chao, and M. J. Cheng, "The Spalling Modes and Degradation Mechanism of ZrO2-8wt%Y2O3/ CVD-Al2O3/ Ni-22Cr-10Al-1Y Thermal-Barrier Coatings", Oxidation of Metals, Vol.40, No.5/6, pp. 465-473 (1993).
23. A. Bahadur and O. N. Mohanty, "Strucural Studies of Hot Dip Aluminized Coateings on Mild Steel", Materials Transactions, Vol.12, No.11, pp. 1053-1061 (1991).
24. 李美栓，金屬的高溫腐蝕，北京冶金工業出版社，第45頁-第46頁，北京，2001。
25. P. L. Daniel and R. A. Rapp, "Halogen Corrosion of Metals", Advances in Corrosion Science and Technology, Vol.5, pp. 55 (1976).
26. O. Kub and E. II. Erans, in: Metallurgical Thermo-Chemistry, Pergamion, New York, pp. 225 (1958).
27. M. J. McNallan and G. Y. Lai S. Thongten, in: Corrosion, NACE, Houston, Texas, pp. 372 (1986).
28. M. Spiegel, A. Zahs and H. Grabke, "The influence of alloying elements on the chlorine-induced high temperature corrosion of Fe-Cr alloys in oxidizing atmospheres", Materials and Corrosion, Vol.50, No.10, pp. 561-578 (1999).
29. H.Ohgame, K. Sakiyama and Y. Ihara, "The Corrosion Behavior of Iron in Hydrogen Chlorine Gas and Gas Mixtures of Hydrogen Chloride and Oxygen at High Temperatures", Corrosion Science, Vol.21, No.12, pp. 805 (1981).
30. S. Y. Lee and M. J. McNallan, "Inhibition of Oxidation of Iron in Environments Containing Chlorine at 1100 and 1200K", J. Electrochem. Soc., Vol.137, No.2, pp. 472 (1990).
31. H.Ohgame and K. Sakiyama Y. Ihara, "The Corrosion Behavior of Chromiun in Hydrogen Chlorine Gas and Gas Mixtures of Hydrogen Chloride and Oxygen at High Temperature", Corrosion Science, Vol.23, No.2, pp. 167 (1983).
32. M. Hara, Y. Shinata, and T. NaKagawa, "Accelerated Oxidation of Chromium by Trace of Sodium Chloride Vapor", Metweials Transaction, JIM, Vol.32, No.10, pp. 969 (1991).
33. C.A.C Sequeira and M.G. Hocking, "Hot Corrosion of Nimonic 105 in Sodium Sulfate-Sodium Chloride Melts", Corrosion-NACE, Vol.37, No.7, pp. 392~407 (1981).
34. M. J. Graham and R. Prescott, "The Formation of Aluminum Oxide Scales on High-Temperature Alloys", Oxidation of Metals, Vol.38, No.3/4, pp. 233 (1992).
35. S. Kim and M. J. McNallan, "Mixed Oxidation of Iron-Chromiun Alloys in Gases Containing Oxygen Chlorine at 900 to 1200K", Corrosion, Vol.46, No.9, pp. 746 (1990).
36. H. Ohgame, K. Hashimoto and Y. Ihara, "Hot corrosion of Fe-Cr alloys in Hydrogen Chloride Gas and Gas Mixtures of Hydrogen Chloride and Oxygen", Transation of the Japan Institute of Metal, Vol.25, No.2, pp. 96 (1984).
37. C. Kawai and A. Yamakawa, "Crystal Growth of Silicon Nitride Whiskers Through a VLS Mechanism Using SiO2-Al2O3-Y2O3 Oxides as Liquid Phase", Ceramics International, Vol.24, pp. 135-138 (1998).
38. G. Jiang, G. Peng, H. Zhuang, W. Li and S. Xu, "Fabrication of β-Si3N4 whiskers by combustion synthesis with MgSiN2 as additives", Materials Research Bulletin, Vol.40, pp. 2139-2143 (2005).
39. H. Uk Joo and W. S. Jung, "Catalytic growth of aluminum nitride whiskers by a modified carbothermal reduction and nitridation method", Journal of Crystal Growth, Vol.285, pp. 566-571 (2005).
40. J. Tartaj and G. Messing, "Anistropic Grain Growth in α-Fe2O3-Doped Alumina", Journal of the Eurpean Ceremic society, Vol.17, pp. 719-725 (1997).
41. C. Badini and F. Laurella, "Oxdation of FeCrAl alloy: influence of temperature and atmosphere on scale growth and mechanism", Surface and Coatings Technology, Vol.135, pp. 291 (2001).
42. J. D. Kuenzly and D. L. Douglass, "Oxidation Mechanism of Ni3Al Coating Yttrium", Oxidation of Metals, Vol.8, pp. 139 (1974).
43. P. T. Moseley and K. R. Hyde, "The microstructure of the scale formed during the high temperature oxidation of a Fe-Cr alloy steel", Corrosion Science, Vol.24, No.6, pp. 547-565 (1984).
44. H. Chen, Y. Su, and W. Y. Lee, "Abnormal grain growth during rapid annealing of sol-gel alumina thin film depositied on Ni-based superalloy", The Ameriacan Ceremic Society, Vol.88, No.11, pp. 3235-3237 (2005).
45. G.M. Raynand and R. A. Rapp, "in suti observation of whiskers, pyramids and pits during the high-temperature oxidation of metals", Oxidation of Metals, Vol.21, No.1-2, pp. 89-102 (1984).
46. E. P. Butler, E. T. Mitchell and D. A. Voss, "Growth of Hematite Blades During the High Temperature Oxidation of Iron", Metallurgical Transaction A(Physical Metallurgy and Materials Science), Vol.13A, No.5, pp. 929 (1982).
47. L. Mikkelsen and S. Linderoth, "High temperture oxidation of Fe-Cr alloy in O2-H2-H2O atmosphere; microstructure and kinetics", Materials Science and Engineering A361, pp. 198 (2003).
48. U Lindborg, "Observations on the Growth of Whisker Crystals from Zinc Electroplate", Metallurgical, Vol.6, No.8, pp. 1581-1586 (1975).
49. Reima Lahtinen, and Tom E. Gustafsson, "The Driving Force Behind Whisker Growth", Metal Finishing., Vol. November, pp. 25-28 (2005).
50. P. Elliott and G. Marsh, "The Oxidation of Incoloy 800 in Moist Air Containning HCl(g) At 800℃", Corrosion Science,Vol. 24, No. 12, pp. 398 (1983).
51. M. Spiegel, H. J. Grabke and A. Zahs, "Chloination and oxidation of iron, chromium, nickel and their alloys in chloridizing and oxidizing atmopheres at 400-700℃", Corrosion Science, Vol.42, pp. 1093 (2000).
52. C. J. Wang, J. G. Duh and J. W. Lee., "NaCl-induced accelerated oxidation of 304 stainless steel and Fe-Mn-Al alloy at 900℃", Journal of Materials science, Vol.38, pp. 3619-3628 (2003).
53. V.A.C. Haanappel and N.W.J Haanappel, "Corrosion Kinetics of Low and High alloy Steel in Chlorine-containing Gad Atmosphere", Corrosion, Vol.48, No.10, pp. 812-821 (1992).