锌对磷酸铝粘结剂及涂层防腐蚀性能的影响  

Influence of Zinc on Aluminum Phosphate Binder and Corrosion Resistance of Its Coating

作　　者：梁海聪 谷坤明[1] 邓远名[1] 戴雷 唐知桥 汤皎宁[1] LIANG Hai-cong1, GU Kun-ming1, DENG Yuan-ming1, DAI Lei2, TANG Zhi-qiao2, TANG Jiao-ning1(1. College of Materials Science and Engineering, Shenzhen University, Shenzhen 518000, China; 2. Guangdong Huacai Industry Co., Ltd., Shenzhen 518000, China)

机构地区：[1]深圳大学材料学院,广东深圳518000 [2]广东华材实业股份有限公司,广东深圳518000

出　　处：《材料保护》2018年第9期12-17,共6页Materials Protection

摘　　要：目前,还未见在磷酸铝涂层中引入锌研究其防腐蚀性能的报道。采用直接法合成了不同锌含量的Al(H_2PO_4)_3粘结剂,并在20G钢上制备出一系列涂层。SEM和XRD分析表明烧结后的粘结剂是致密连续的,且主要固化产物为不同晶型的Al(PO_3)_3。DSC分析表明锌的引入可降低磷酸二氢铝粘结剂的初步固化温度,烧结后在粘结剂中形成尺寸约为8μm的鳞片状Zn(PO_3)_2晶体。随着室温存储时间延长,鳞片状的Zn(PO_3)_2晶体会有所长大。晶体的引入可减少粘结剂烧结后因体积收缩而产生的裂纹、孔洞等缺陷。耐酸液体介质腐蚀性、耐高温熔盐腐蚀性以及电化学极化曲线等测试均表明,鳞片状的Zn(PO_3)_2晶体对磷酸盐涂层产生了屏蔽效应,增强了其耐腐蚀性能。Aluminum dihydrogen phosphate binder with different zinc content and a series of coatings were prepared on 20G steel by direct synthesis. SEM and XRD analysis showed that the sintered binder was dense and continuous, and the main curing product was Al（ PO3 ）3 in two crystalline forms. DSC analysis presented that the addition of zinc reduced the initial curing temperature of the aluminum dihydrogen phosphate binder, and some scale-like Zn（ PO3 ） 2 crystals could form in the binder after sintering. The scaly Zn（ PO3 ） 2 crystals grew slowly as the binder was stored at room temperature. Moreover, the introduction of these crystals could reduce defects （ holes or cracks） of the binder, which were resulted from sintering shrinkage. The corrosion tests including acid-medium corrosion, high-temperature corrosion and electrochemical polarization curves indicated that these scale-like Zn（ PO3 ）2 crystals could help the phosphate coatings from corrosion by shielding effect.

关 键 词：锌含量 磷酸铝粘结剂 偏磷酸锌 烧结 防腐蚀涂层 

分 类 号：TQ630.1[化学工程—精细化工]