(1. 常州大學(xué) 先進(jìn)金屬材料常州市重點(diǎn)實(shí)驗(yàn)室，常州 213164；
2. 常州大學(xué) 江蘇省油氣儲(chǔ)運(yùn)技術(shù)重點(diǎn)實(shí)驗(yàn)室，常州 213016；
3. 湘潭大學(xué) 材料設(shè)計(jì)及制備技術(shù)湖南省重點(diǎn)實(shí)驗(yàn)室，湘潭 411105)
摘 要: 通過(guò)熱浸鍍和擴(kuò)散偶試驗(yàn)研究鐵基與4種鋅鋁熔池成分合金Zn-0.2%Al、Zn-5%Al、Zn-25%Al、Zn-55%Al(質(zhì)量分?jǐn)?shù))之間的界面反應(yīng)過(guò)程，提出熱浸鍍鋅鋁中擴(kuò)散通道移動(dòng)對(duì)合金層形成的控制機(jī)理。結(jié)果表明：熱浸鍍(擴(kuò)散偶)初期，擴(kuò)散通道均沿兩相區(qū)共軛線(tie-line)穿過(guò)熔池成分液相與對(duì)應(yīng)的Fe-Al化合物構(gòu)成的兩相區(qū)，鐵基表面優(yōu)先形成對(duì)應(yīng)的Fe-Al化合物的連續(xù)層狀組織。隨著熱浸鍍(擴(kuò)散)時(shí)間的延長(zhǎng)，擴(kuò)散通道具有逐漸向兩擴(kuò)散組元成分點(diǎn)連線移動(dòng)的趨勢(shì)，一旦擴(kuò)散通道切割熔池成分液相與對(duì)應(yīng)的Fe-Al化合物構(gòu)成的兩相區(qū)共軛線，初期形成的Fe-Al化合物層失穩(wěn)破裂，導(dǎo)致鍍層合金層(擴(kuò)散層)快速增厚。
關(guān)鍵字: 熱浸鍍鋅鋁；擴(kuò)散偶；Zn-Fe-Al體系；界面反應(yīng)；擴(kuò)散通道
（1. Key Laboratory of Advanced Metal Materials of Changzhou City, Changzhou University, Changzhou 213164, China;
2. Key Laboratory of Oil and Gas Storage and Transportation Technology of Jiangsu Province,
Changzhou University, Changzhou 213016, China;
3. Key Laboratory of Materials Design and Preparation Technology of Hunan Province, Xiangtan University,
Xiangtan 411105, China）
Abstract:By galvanizing and diffusion couple experiments, the interface reactions between the iron-base and different baths, which are Zn-0.2%Al, Zn-5%Al, Zn-25%Al and Zn-55%Al (mass fraction), were studied, respectively. The controlled mechanism of alloy layer formation in the process of galvanizing by the diffusion path change was proposed. The results show that in the beginning of galvanizing (diffusion couple), the diffusion path crosses the two-phase region of melting bath point composition and the relevant Fe-Al compound following its tie-line, the Fe-Al compound forms on the iron-based surface firstly. With the immersion (diffusion) time increasing, the diffusion path trends to move gradually to the line connecting with two diffusion component points. Once the diffusion path cuts the tie-line of the two-phase region of melting bath and the relevant Fe-Al compound, the first Fe-Al compound layer is steadiness losing and breaking, which makes the thickness of coating alloy layer (diffusion layer) increase rapidly.
Key words: hot-dipping Zn-Al; diffusion couple; Zn-Fe-Al system; interface reaction; diffusion path
