Wettability of Zn-Al alloy melt on the pure iron substrate at 450℃was studied.The effect of Al content(Zn,Zn-1Al,Zn-2Al,Zn-3Al,Zn-4Al,and Zn-5Al)on the wetting behavior and interfacial reaction was investigated by hi...Wettability of Zn-Al alloy melt on the pure iron substrate at 450℃was studied.The effect of Al content(Zn,Zn-1Al,Zn-2Al,Zn-3Al,Zn-4Al,and Zn-5Al)on the wetting behavior and interfacial reaction was investigated by high-temperature contact angle measuring device and scanning electron microscope(SEM).The results show that,with the increase of Al content,the initial contact angle of the molten alloy on the substrate decreases gradually and the wettability increases gradually.Compared with the initial contact angle,the final contact angle is slightly reduced,because the Fe-Al inhibition layer is preferentially formed at the interface when adding Al to the alloy.The presence of Al will promote the occurrence of the reactive wetting,leading to an insignificant wetting spreading process,and the final contact angle negligibly differs from the initial contact angle.The adhesion work and charge density distributions of interface systems were calculated based on the first-principles.The results show that the adhesion work of the Fe/Zn and Fe/(Zn-Al)interface model is 2.0171 J/m^(2)and 13.7944 J/m^(2),respectively.The addition of Al greatly increases the adhesion work between alloy melt and iron substrate.Compared with the Zn-Fe and Al-Fe interface models,it can be seen that a significant charge migration phenomenon occurs between the interfaces.The amount of charge migration in the Al-Fe interface model is much larger than that in the Zn-Fe interface model,indicating that the bonding between Al-Fe atoms can occur more easily and the interaction between Al-Fe interfaces is stronger.This is also the reason why the addition of Al increases the adhesion work between interfaces.展开更多
采用扫描电镜(SEM)、能谱仪(EDS)、X射线衍射(XRD)、腐蚀电化学、失重法等方法研究了X80管线钢内外壁氧化层微观组织对10%HCl酸洗液中酸洗过程的影响。研究表明,内外壁氧化层均由Fe 3 O 4构成的致密高温氧化层和α-FeOOH,γ-FeOOH构成...采用扫描电镜(SEM)、能谱仪(EDS)、X射线衍射(XRD)、腐蚀电化学、失重法等方法研究了X80管线钢内外壁氧化层微观组织对10%HCl酸洗液中酸洗过程的影响。研究表明,内外壁氧化层均由Fe 3 O 4构成的致密高温氧化层和α-FeOOH,γ-FeOOH构成的疏松锈层组成,外壁存在明显凹坑缺陷。在酸洗过程中,内外壁表面疏松锈层优先酸洗,20 s后内外壁高温氧化层露出细微裂缝缺陷,酸液可以渗入裂缝直接与基体发生腐蚀,促进局部高温氧化层剥落,从而加速酸洗,酸洗至60 s时内壁酸洗完成,而外壁凹坑内高温氧化层较厚至90 s时才酸洗完成。展开更多
基金Funded by the National Natural Science Foundation of China(Nos.51971039,51671037)the Natural Science Research Project of Higher Education of Jiangsu,China(No.19KJA530001)Postgraduate Research&Practice Inovation Program of Jiangsu Province(No.KYCX20-2574)
文摘Wettability of Zn-Al alloy melt on the pure iron substrate at 450℃was studied.The effect of Al content(Zn,Zn-1Al,Zn-2Al,Zn-3Al,Zn-4Al,and Zn-5Al)on the wetting behavior and interfacial reaction was investigated by high-temperature contact angle measuring device and scanning electron microscope(SEM).The results show that,with the increase of Al content,the initial contact angle of the molten alloy on the substrate decreases gradually and the wettability increases gradually.Compared with the initial contact angle,the final contact angle is slightly reduced,because the Fe-Al inhibition layer is preferentially formed at the interface when adding Al to the alloy.The presence of Al will promote the occurrence of the reactive wetting,leading to an insignificant wetting spreading process,and the final contact angle negligibly differs from the initial contact angle.The adhesion work and charge density distributions of interface systems were calculated based on the first-principles.The results show that the adhesion work of the Fe/Zn and Fe/(Zn-Al)interface model is 2.0171 J/m^(2)and 13.7944 J/m^(2),respectively.The addition of Al greatly increases the adhesion work between alloy melt and iron substrate.Compared with the Zn-Fe and Al-Fe interface models,it can be seen that a significant charge migration phenomenon occurs between the interfaces.The amount of charge migration in the Al-Fe interface model is much larger than that in the Zn-Fe interface model,indicating that the bonding between Al-Fe atoms can occur more easily and the interaction between Al-Fe interfaces is stronger.This is also the reason why the addition of Al increases the adhesion work between interfaces.