Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/2074
標題: 304不銹鋼之初氧化機構及其抗蝕特性之研究
steel reserch
作者: 吳英政
Y.J.WU
關鍵字: stainless steel;不銹鋼;oxidation;corrosion;氧化;腐蝕
出版社: 機械工程研究所
摘要: 
304不銹鋼氧化表面形態、化學組成及厚度對腐蝕阻抗的關聯性是本研究
探討的主題,為釐清不同氧化處理所導致表面性質的差異,有必要對氧化機
構與電化學性質作詳細分析,所進行的實驗包括TGA 動態氧化分析、OM及
SEM氧化表面形態觀察分析、氧化層元素縱深分布(AES)與標準電化學分
析.由實驗結果顯示在氧化反應早期階段是以界面控制為主的反應機制,此
期以滿足熱力學定律為準則,此時表面是由均勻而緻密的富鉻氧化膜生成,
所呈現的電化學性質亦顯示擁有較佳的抗腐蝕性,而後續的氧化成長則端
賴各元素於先前緻密膜內的擴散速率所決定,此時是以擴散控制為主要的
反應機制,同時表面逐漸有富鐵氧化物的析出,由於鐵氧化物孔隙度較大而
所呈現的電化學特性亦較差,實驗中同時發現過長氧化時間與過高氧化溫
度本身擁有較差的電化學特性,歸究其原因可能是由於表面的不均勻、熱
溝效應( thermal grooving)以及材料受敏化所導致晶界附近抗蝕能力降
低而造成沿晶腐蝕等;而厚度與抗蝕性能間的正比關係,則顯示在較低溫度
與較短時間下較為明顯.
The correspondence between the surface morphology、chemical
composition、thickness and the corrosion resistance of the
thermal oxidation film on AISI 304 stainless steel is the
subject of this study . In order to clarify the relationship
between oxidation mechanism and electrochemical characteristics,
many experiment have been proceeded, such as dynamic TGA
(Thermal Gravitational Analysis),OM (Optical microscopy) and
SEM-EDAX( Scanning Electron Microscopy with Energy-Dispersive
Analysis of X-rays)、AES (Auger Electron Spectroscopy) depth
profiling of oxide composition and standard electrochemical
polarization . It has been demostrated that the early stage of
oxidation is a mechanism of interface controlled reaction and a
dense chromium-rich oxide film,with good corrosion resistance,
is rmed.After the early stage ,the later oxidation is a
diffusion controlled reaction which depends on the diffusivity
of alloy elements in the chromium-rich oxide film .At this
stage, adular iron-rich oxide is found on the top layer of the
oxidewhich shows the worse corrosion resistance,probably due to
the porosity of iron oxide oxide film,thermal grooving for long
time annealing,and the sensitizing of chromium carbide is the
grain boundary.However,the corrosion resistance of the oxide
film is proportional to the thickness for a shorter time
oxidation and a lower oxidation temperature .
URI: http://hdl.handle.net/11455/2074
Appears in Collections:機械工程學系所

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