Effect of K<sub>2</sub>HPO<sub>4</sub> Concentration on the Formation, Structure, Composition and Protectiveness of Conversion Coating Deposited on AZ31 Magnesium Alloy

doi:10.1007/s40195-025-01815-3

IMR OpenIR

	Effect of K₂HPO₄ Concentration on the Formation, Structure, Composition and Protectiveness of Conversion Coating Deposited on AZ31 Magnesium Alloy
	Wu, Liping 1; Dong, Junhua 1; Zheng, Xianfei 2; Wang, Zhongying 3; Sun, Xiaoying 4; Shang, Xiuling 4; Ke, Wei 1; Wang, Changgang 1
通讯作者	Dong, Junhua(jhdong@imr.ac.cn) ; Wang, Changgang(cgwang@imr.ac.cn)
	2025-01-22
发表期刊	ACTA METALLURGICA SINICA-ENGLISH LETTERS
ISSN	1006-7191
页码	16
摘要	In deaerated 0.05 M, 0.1 M, 0.2 M and 0.5 M K2HPO4 solutions with pH 9.5, AZ31 magnesium (Mg) alloy was subjected to potentiostatic polarization at - 0.8 VSCE to deposit a phosphate conversion coating. The morphology, structure, chemical composition, and protective performance of the conversion coating during the formation process were characterized. The results showed that amorphous Mg(OH)2 and MgHPO4 and crystallized KMgPO46H2O (struvite-K) were successively deposited on the surface of AZ31 Mg alloy in the four solutions. MgHPO4 was converted from Mg(OH)2, while struvite-K was transformed from MgHPO4. The distribution of Mg(OH)2, MgHPO4 and struvite-K along the thickness of the coating differs with K2HPO4 concentration. As the concentration of K2HPO4 increased, the coating time was gradually shortened, and the coating was gradually thinned. Meanwhile, the ratio of the nucleation rate to the growth rate of struvite-K crystal nuclei increased, resulting in a decrease in the size of struvite-K crystal. When the concentration of K2HPO4 increased from 0.05 to 0.1 M, the content of struvite-K increased, and the protective performance of the coating was enhanced. However, as the concentration of K2HPO4 continued to increase to 0.5 M, the content of struvite-K and the protective performance of the coating decreased.
关键词	Magnesium alloy Potentiostatic technique Phosphate coating
资助者	National Natural Science Foundation of China
DOI	10.1007/s40195-025-01815-3
收录类别	SCI
语种	英语
资助项目	National Natural Science Foundation of China[52373322]
WOS研究方向	Metallurgy & Metallurgical Engineering
WOS类目	Metallurgy & Metallurgical Engineering
WOS记录号	WOS:001401149300001
出版者	CHINESE ACAD SCIENCES, INST METAL RESEARCH
引用统计
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/180267
专题	中国科学院金属研究所
通讯作者	Dong, Junhua; Wang, Changgang
作者单位	1.Chinese Acad Sci, Inst Met Res, Shenyang 110016, Peoples R China 2.Changda Hosp, Anshan 114000, Peoples R China 3.Ansteel Grp Corp Gen Hosp, Anshan 114000, Peoples R China 4.Guangdong Midea Air Conditioning Equipment CO LTD, Foshan 528311, Peoples R China
推荐引用方式 GB/T 7714	Wu, Liping,Dong, Junhua,Zheng, Xianfei,et al. Effect of K₂HPO₄ Concentration on the Formation, Structure, Composition and Protectiveness of Conversion Coating Deposited on AZ31 Magnesium Alloy[J]. ACTA METALLURGICA SINICA-ENGLISH LETTERS,2025:16.
APA	Wu, Liping.,Dong, Junhua.,Zheng, Xianfei.,Wang, Zhongying.,Sun, Xiaoying.,...&Wang, Changgang.(2025).Effect of K₂HPO₄ Concentration on the Formation, Structure, Composition and Protectiveness of Conversion Coating Deposited on AZ31 Magnesium Alloy.ACTA METALLURGICA SINICA-ENGLISH LETTERS,16.
MLA	Wu, Liping,et al."Effect of K₂HPO₄ Concentration on the Formation, Structure, Composition and Protectiveness of Conversion Coating Deposited on AZ31 Magnesium Alloy".ACTA METALLURGICA SINICA-ENGLISH LETTERS (2025):16.