Effects of pre-treatments on the corrosion properties of electroless Ni–P layers deposited on AlMg2 alloy

The influence of pulse plating parameters on microstructure and properties of Ni-W-Si3N4 nanocomposite coatings

“…As frequency increased, Si 3 N 4 content in the coatings increased and crystallite size of the coatings reduced which leading to the number of grain boundaries increasing. The nanoparticles in the composite coatings block the dislocations motion and the grain boundaries sliding of the matrix which leads to the dislocation's pile up, consequently stress concentration and hardness increase [35]. In addition, microhardness of polycrystalline materials increases with decreasing crystallite size and the result obtained in the present case with respect to the size of the nanocomposites is in accordance [11].…”

Chromium Electroplating of Aluminium Alloys Using Electroless Nickel as Underlayer

“…Takacs et al [6] studied the effects of pre-treatment on the corrosion properties of electroless Ni-P layers deposited on AlMg2 alloy. Using a measure of polarisation resistances, they found that the nickel pre-coating and the hypophosphite adlayer formed by suitable immersion pre-treatments improved the corrosion resistance of the samples immersed in aerated sodium sulphate solution.…”

Investigation of a transparent chromate (III) passive film on electroless Ni–P coating by XPS and electrochemical methods

“…Electroless nickel method can coat a Ni-P alloy layer on many substrates such as metal, plastic, glass and ceramic through an autocatalytic process in which complex nickel ions are chemically reduced and deposited on substrates [1][2][3][4][5][6][7][8][9][10][11]. This alloy layer owns many advantages such as uniform deposition, good corrosion and wear resistance, perfect electrical and thermal conductivity, and solderability [12][13][14][15].…”

“…As the pH value rising, metal ions cannot stay stably in solution and consequently form insoluble hydroxides to precipitate on matrixes, as described in Eqs. (2) and (3).…”

“…(2) and (3), surface of the matrixes will be gradually covered by insoluble compounds, Eq. (1) slows down, which in turn decelerates Eqs.…”