Effective and Environmentally Friendly Nickel Coating on the Magnesium Alloy

Abstract

Abstract:The low density and good mechanical properties make magnesium and its alloys attractive construction materials in the electronics, automotive, and aerospace industry, together with application in medicine due to their biocompatibility. Magnesium AZ91D alloy is an alloy with a high content of aluminum, whose mechanical properties overshadow the low corrosion resistance caused by the composition of the alloy and the existence of two phases: α magnesium matrix and β magnesium aluminum intermetallic compound. To improve the corrosion resistance, it is necessary to find an effective protection method for the alloy surface. Knowing and predicting electrochemical processes is an essential for the design and optimization of protective coatings on magnesium and its alloys. In this work, the formations of nickel protective coatings on the magnesium AZ91D alloy surface by electrodeposition and chemical deposition, are presented. For this purpose, environmentally friendly electrolytes were used. The corrosion resistance of the protected alloy was determined in chloride medium using appropriate electrochemical techniques. Characterization of the surface was performed with highly sophisticated surface-analytical methods.

Electrodeposition of hydroxyapatite coating on Mg alloy modified with organic acid self-assembled monolayers

“…Confirmation: peaks at 1103 and 1017 cm −1 that can be attributed to the stretching vibration of the P–O bond. 51…”

“…Confirmation: peaks at 1103 and 1017 cm −1 that can be attributed to the stretching vibration of the P-O bond. 51 In the FTIR spectrum of the Mg alloy surface modified with ODPA|HAp film, the peak of low intensity at about 2350 cm −1 confirms the presence of free P-OH groups and suggests the presence of several different binding modes of the phosphonic group. 51 Two fine-resolved ν3 bands at 1015 and 1086 cm −1 that can be attributed to the asymmetric P-O stretching 39,45,52 indicate that the HAp coating is a crystalline.…”

“…17 In this sense, it is essential to have well-defined and reproducible surfaces which are relatively easy to form by selfassembled monolayers (SAMs) of biomolecules like alkylcarboxylic acids 26,27 and alkylphosphonic acids. [27][28][29] It has been shown that surfaces modified by SAMs bearing various functional end groups have a significant effect on the chemical precipitation and nucleation of CaP. [30][31][32][33] Some functional groups ( PO H 4 2 − , COO − SO H 3 − , and OH − ) 31,[33][34][35] were confirmed to have the ability to induce bone-like apatite nucleation through a biomimetic route.…”

“…tilt-angle). 29,36 In this study, HAp coating formation was studied on well-defined surfaces using organic SAMs (stearic acid (SA) or octadecylphosphonic acid (ODPA)) on Mg alloy (Mg93Al6Zn1 alloy). The Ca/P coating was prepared by electrodeposition from a solution containing Ca 2+ and H PO 2 4…”

Znanstveno-istraživačka djelatnost Zavoda za opću i anorgansku kemiju u razdoblju 2010. – 2020.

“…15 Nadalje, istraživana su dva načina formiranja zaštitne prevlake od nikla na površini magnezijeve AZ91D legure: elektrodepozicijom i kemijskim taloženjem. 16 U tu svrhu upotrijebljeni su ekološki prihvatljivi elektroliti. Dva su osnovna razloga za poteškoće koje se javljaju kod oba načina formiranja zaštitne prevlake od nikla na površini magnezijevih legura.…”