The Influences of Additives on the Corrosion Resistant Properties of Electroless Plating Ni-Co-P Alloy on the AZ91D Magnesium Alloy

2014 ◽  
Vol 1004-1005 ◽  
pp. 733-736
Author(s):  
Zu Xiao Yu ◽  
Ya Li Sun ◽  
Xin Huang
Keyword(s):  
Magnesium Alloy ◽  
Deposition Rate ◽  
Electroless Plating ◽  
Acid Resistance ◽  
Ammonium Fluoride ◽  
Alloy Coating ◽  
Corrosion Current ◽  
Corrosion Properties ◽  
Corrosion Resistant ◽  
Az91d Magnesium Alloy

To improve the anti-corrosion properties of the AZ91D magnesium alloy, the electroless plating Ni-Co-P on the AZ91D magnesium alloy is necessary. The influences of additives (ammonium fluoride (NH4F) and hexamethylenetetramine (HMTA)) on deposition rate, corrosion rate, acid resistance, corrosion current, corrosion potential and webster hardness of electroless plating Ni-Co-P alloy coating, were investigated using electrochemical methods, etc. The results show that the deposition rate and corrosion resistance properties of electroless plating Ni-Co-P are obviously improved when the additives, including NH4F (2%) and hexamethylenetetramine (HMTA, 1%), are added into plating solution, respectively. In addition, the global particles in the Ni-Co-P coating become smaller with the addition of NH4F by comparison with no additives and coatings are dense, uniform and defect-free.

The Influences of Additives on the Corrosion Resistant Properties of Electroless Plating Ni-W-P Alloy on the Aluminum

2015 ◽  
Vol 723 ◽  
pp. 860-863
Author(s):  
Zu Xiao Yu ◽  
Shi Xiong Hao ◽  
Lan Li ◽  
De Tao Zheng
Keyword(s):  
Corrosion Resistance ◽  
Deposition Rate ◽  
Electroless Plating ◽  
Corrosion Potential ◽  
Electrochemical Impedance ◽  
Alloy Coating ◽  
Corrosion Current ◽  
Corrosion Properties ◽  
Corrosion Resistant ◽  
Plating Solution

To improve the anti-corrosion properties of the aluminum, the electroless plating Ni-W-P on the aluminum is necessary. Investigation was made on the influences of additives (stabilizers and surfactants) on the deposition rate, weight loss corrosion rate, porosity, corrosion current, corrosion potential, electrochemical impedance spectroscopy (EIS) and webster hardness of electroless plating Ni-W-P alloy coating by electrochemical methods, etc. The results show that the deposition rate and anti-corrosion properties of electroless plating Ni-W-P are obviously improved when the stabilizer KIO3 (1mg/L) is added into plating solution. In addition, the Ni-W-P coating become more dense, uniform and defect-free with the addition of stabilizer KIO3 by comparison with no stabilizer. When the surfactant SDBS (50mg/L) added into bath, the corrosion resistance properties of electroless plating Ni-W-P alloy coating are also obtained.

The Influences of Additives and Heat Treatment on the Properties of Electroless Plating Ni-W-Mo-P Alloy on the Aluminum

2014 ◽  
Vol 941-944 ◽  
pp. 1585-1588
Author(s):  
Zu Xiao Yu ◽  
De Tao Zheng ◽  
Hong Guo ◽  
Yong Liu ◽  
Yuan Liang Luo ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Wear Resistance ◽  
Corrosion Resistance ◽  
Deposition Rate ◽  
Electroless Plating ◽  
Corrosion Potential ◽  
Alloy Coating ◽  
Corrosion Current ◽  
Maximum Hardness ◽  
Corrosion Properties

To improve the wear resistance and anti-corrosion properties of the aluminum, the electroless plating Ni-W-Mo-P alloy on the aluminum is necessary. The influences of heat treatment and additives (stabilizers) on the porosity, deposition rate, corrosion current, corrosion potential, microhardness and wear resistance of electroless plating Ni-W-Mo-P alloy coating, were investigated using electrochemical methods, etc. The results show that the deposition rate and anti-corrosion properties of electroless plating Ni-W-Mo-P are improved when the stabilizers, including KI (1mg/L) and “KIO3 (1mg/L) + Pb (Ac)2 (1mg/L)”, are added into bath, respectively. In addition, the maximum hardness (902 HV) and good wear resistance of Ni-W-Mo-P coatings are obtained when heated at 400°C (1h). However, its corrosion resistance is worse. Its microhardness is also obviously improved after heated at 200°Cfor 6 h, and the microhardness reaches to 950 HV.

Research on Corrosion Resistance of AZ91D Magnesium Alloy Coated with Epoxy Resin

2011 ◽  
Vol 686 ◽  
pp. 292-299
Author(s):  
Yong Gang Li ◽  
Ying Hui Wei ◽  
Li Feng Hou ◽  
Yun Tian ◽  
Li Jing Yang
Keyword(s):  
Corrosion Resistance ◽  
Magnesium Alloy ◽  
Adhesion Force ◽  
Die Casting ◽  
Corrosion Current ◽  
Scratch Test ◽  
Organic Coating ◽  
Thin Wall ◽  
Scanning Method ◽  
Az91d Magnesium Alloy

The corrosion resistance of a 1~2mm thick AZ91D magnesium alloy die-casting coated with epoxy varnish after phosphatizing was tested. Zinc phosphating solution was used. In the experiment, uniform paint was obtained by dipping method. Scratch test showed that the adhesion force between the coating and matrix is excellent. Within the test range the optimal phosphating temperature and time are 50°C and 1 min tested by dynamic potential scanning method. With the organic coating the corrosion current density decreased 3 orders of magnitude, the polarization resistance increased 3 orders of magnitude. The coated specimens were immersed in10% H2SO4, 10% NaOH and acetone for 10 days, respectively. The results showed that blistering did not occur on the paint films. This work illustrated that the simple zinc phosphating process combined with simple organic coating can meet the corrosion resistance requirements of thin-wall die casting magnesium components that require higher quality appearance.

INFLUENCE OF SURFACTANTS ON THE CORROSION PROPERTIES OF CHROMIUM-FREE ELECTROLESS NICKEL DEPOSIT ON MAGNESIUM ALLOY

2012 ◽  
Vol 19 (03) ◽  
pp. 1250025 ◽  
Author(s):  
JOTHI SUDAGAR ◽  
RUAN DEWEN ◽  
YAQIN LIANG ◽  
RASU ELANSEZHIAN ◽  
JIANSHE LIAN
Keyword(s):  
Corrosion Resistance ◽  
Magnesium Alloy ◽  
Electroless Nickel ◽  
Corrosion Current ◽  
Immersion Test ◽  
Electrochemical Polarization ◽  
Nickel Deposit ◽  
Corrosion Properties ◽  
Positive Direction ◽  
Polarization Test

Influence of surfactants on the corrosion properties of chromium-free electroless nickel deposit were investigated on AZ91D magnesium alloy. The corrosion tests were carried out by immersion test (1 M HCl) and electrochemical polarization test (3.5 wt% NaCl ). The surfactants in the electroless nickel bath increases the corrosion resistance properties of the deposit on the magnesium alloy. In addition, smoothness and amorphous plus nano-crystalline phase were increased and accounted for the significant corrosion resistance. As a consequence, the corrosion potential moved towards the positive direction and the corrosion current density decreased. The immersion tests also provided the same trend as that of electrochemical polarization test. On the whole, the study concluded that corrosion resistance was enhanced by including a surfactant in the electroless deposits on magnesium alloy.

Effect of sintering temperature on corrosion properties of sol–gel based Al2O3 coatings on pre-treated AZ91D magnesium alloy

2009 ◽  
Vol 51 (12) ◽  
pp. 2950-2958 ◽  
Author(s):  
Xiankang Zhong ◽  
Qing Li ◽  
Bo Chen ◽  
Juping Wang ◽  
Junying Hu ◽  
...  
Keyword(s):  
Magnesium Alloy ◽  
Sintering Temperature ◽  
Sol Gel ◽  
Corrosion Properties ◽  
Az91d Magnesium Alloy

Preparation and characterization of inorganic and organic coatings on AZ91D magnesium alloy with electroless plating pretreatment

2011 ◽  
Vol 62 (9) ◽  
pp. 841-847 ◽  
Author(s):  
S. Y. Zhang ◽  
Q. Li ◽  
X. K. Yang ◽  
H. X. Zhang ◽  
S. Y. Wang ◽  
...  
Keyword(s):  
Magnesium Alloy ◽  
Electroless Plating ◽  
Organic Coatings ◽  
Az91d Magnesium Alloy ◽  
Inorganic And Organic

Anti-Corrosion Properties of Al-Based Coating on Magnesium Alloy Fabricated by Supersonic Particles Deposition

2013 ◽  
Vol 746 ◽  
pp. 524-528 ◽  
Author(s):  
Xiao Ming Wang ◽  
Sheng Zhu ◽  
Qing Chang ◽  
Xue Qiang Feng ◽  
Guo Feng Han
Keyword(s):  
Magnesium Alloy ◽  
Surface Morphology ◽  
Mass Gain ◽  
Alloy Coating ◽  
Corrosion Property ◽  
Corrosion Products ◽  
Corrosion Properties ◽  
Sem Observation ◽  
Alloy Substrate ◽  
Eds Analysis

In order to improve anti-corrosion property of magnesium alloy parts in equipment, Al-based alloy coating on ZM5 magnesium alloy was prepared by supersonic particles deposition (SPD). Mass gain after being corroded, surface morphology of samples corroded and corrosion products were investigated by salt-mist test, SEM observation and EDS analysis etc. The results indicated that the mass gain of Al-Si coating after being corroded decreased evidently compared with magnesium alloy substrate. Al-Si coatings with thickness above 0.5mm did not generate blisters after 500h salt-mist test, proving that the coating possessed excellent anti-corrosion property.

Corrosion properties of surface-modified AZ91D magnesium alloy

2008 ◽  
Vol 50 (12) ◽  
pp. 3267-3273 ◽  
Author(s):  
He Meifeng ◽  
Liu Lei ◽  
Wu Yating ◽  
Tang Zhixin ◽  
Hu Wenbin
Keyword(s):  
Magnesium Alloy ◽  
Corrosion Properties ◽  
Az91d Magnesium Alloy ◽  
Surface Modified
Sign in / Sign up

Export Citation Format

Share Document