摘要
为了抑制热浸镀锌过程中因含硅活性钢引起的镀层超厚生长,采用在纯锌浴中加Ti的方法,研究了0.09%Si钢在几种Ti含量低于0.1%的锌浴中热浸镀获得的镀层组织,并采用盐雾腐蚀、电化学极化以及X射线光电子能谱等方法,研究了Zn和Zn-Ti镀层的耐蚀性能.结果表明;随着锌浴中Ti含量的增加,Ti对ζ相生长的抑制作用增强,有效地抑制了含硅活性钢镀层的超厚生长,(ζ+δ)合金相层厚度逐渐减薄;当Ti含量大于0.05%时,镀层中出现Γ2粒子;Zn-Ti合金镀层在5%NaC l溶液中发生自发腐蚀的倾向小于Zn镀层,其极化电阻增大,腐蚀电流密度减小,耐蚀性能提高;Zn-Ti镀层表面形成的氧化膜由ZnO和TiO2组成.锌钛合金镀层的耐腐蚀性能优于纯锌镀层是由于在镀层表面形成了更加稳定的TiO2膜.
In order to restrain the excess growth of the coatings induced by reactive steel containing silicon during the hot-dipped galvanizing process, Ti was added in a Zn bath with a mass fraction of less 0. 1% , and the microstructures of the coatings on the steel containing 0. 09% of Si were investigated. Then, the corrosion resistances of Zn and Zn-Ti coatings were studied by means of the neutral salt spray test, the electrochemical polarization and the X-ray photoelectron spectrum. The results show that, with the increase of the Ti content in Zn bath, the growth of ζ phase in the coating is obviously restrained, the excess growth of the coating is thus effectively restrained, and the thickness of ζ ＋ δ phase gradually decreases. It is also indicated that there arise Г2 particles when the Ti content in Zn bath is more than 0.05%, that the Zn-Ti coating in 5% NaCl solution is of lower corrosion current, larger polarization resistance, less spontaneous corrosion tendency and better corrosion resistance than pure Zn coating, and that the oxidized film of Zn-Ti coating is composed of ZnO and TiO2. As a result, the excellent corrosion resistance of Zn-Ti coating is due to the presence of steadier TiO2 film on the coating surface.
出处
《华南理工大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2008年第7期82-86,共5页
Journal of South China University of Technology(Natural Science Edition)
关键词
热浸镀锌
Zn—Ti镀层
显微组织
耐蚀性能
hot-dipped galvanizing
Zn-Ti coating
microstructure
corrosion resistance
