A review on the corrosion resistance of electroless Ni-P based composite coatings and electrochemical corrosion testing methods

Abstract

This paper aims to review the impact of different factors influencing the corrosion resistance of electroless Ni-P based coatings. Emphasis has been given onto the impact of phosphorus content, incorporation of alloying elements, addition of particles and heat treatment which have been discussed in detail and critically reviewed. The effect of corrosive media and coating process parameters on corrosion resistance are studied concisely. Furthermore, the role of the incorporation of various elements and particles’ contents on the corrosion resistance of electroless Ni-P coating are studied systematically. This paper also presents an overview of the latest electrochemical corrosion measuring techniques. The following approaches deserve special attention in the analysis: localized electrochemical impedance spectroscopy (LEIS), scanning vibrating electrode technique (SVET), scanning ion-selective electrode technique (SIET), scanning droplet cell (SDC), scanning electrochemical microscopy (SECM), scanning Kelvin probe (SKP) and novel contactless technique (NCT).

Electroless Ni-P-MoS2 composite coating of Al-alloys: effect of surface textures and bath composition

“…The use of ZrO 2 nanoparticles in the EL-bath increase the microhardness of the coated samples, which further improves by heat treatment procedures [19]. Some other materials used to contaminate the EL-bath for obtaining vicious properties include graphene, SiO 2 , TiH 2, SiC, BN, Al 2 O 3 , TiO 2 , CNTs, etc [20][21][22][23][24]. The urge to obtain wear resistance properties has attracted the research fraternity to use solid lubricating powders such as MoS 2 , WS 2 , CNTs, etc in the EL-coating baths [2,8].…”

Prospect of Using Machine Learning-Based Microwave Nondestructive Testing Technique for Corrosion Under Insulation: A Review

“…The induced AC is measured at the resistor, RIN, to obtain the value of VCPD [98]. The corrosion potential of the sample interface impacts and varies linearly to the VCPD [100].…”

Unraveling the Catalytic Graphitization Mechanism of Ni–P Electroless Plated Cokes via In Situ Analytical Approaches

“…The amorphous nature contributes to a more uniform and homogeneous coating, which is less likely to have defects like pores or cracks that can initiate corrosion. 33 In addition, the electroless plating process allows for a controlled and uniform deposition of the Ni−P alloy, ensuring consistent coverage and thickness. 34,35 This uniformity is essential for providing consistent corrosion resistance across the entire coated surface.…”

“…Controlling the deposition rate by phosphorus introduction allows for a more even and consistent distribution of the nickel layer across complex geometries and surfaces. , Ni–P alloys have an amorphous or microcrystalline structure, especially when the phosphorus content is high. The amorphous nature contributes to a more uniform and homogeneous coating, which is less likely to have defects like pores or cracks that can initiate corrosion . In addition, the electroless plating process allows for a controlled and uniform deposition of the Ni–P alloy, ensuring consistent coverage and thickness. , This uniformity is essential for providing consistent corrosion resistance across the entire coated surface.…”