Tribological and Corrosion Performance of Electrodeposited Nickel Composite Coatings

The inclusion of second-phase particles in nickel-based matrix to fabricate composite coatings presents a promising solution to combating corrosion and wear deterioration of materials during service. Composite coatings possess better surface properties such as wear resistance, high microhardness, thermal stability, and corrosion resistance than the traditional nickel coatings. Their excellent properties enable them to be used in advanced industrial applications where they will be constantly exposed to severe and degrading environments. There are various surface modification techniques that are employed to produce these coatings and electrodeposition has received wide range of use in fabrication of nickel matrix composites. This technique is associated with low cost, simplicity of operation, versatility, high production rates, and few size and shape limitations. To produce advanced electrodeposits with better performance during application, the optimization and further developments of the process remain vital. Therefore, this chapter aims to review the electrofabrication and properties of nickel composite/nanocomposite coatings for corrosion and wear applications

Fabrication and Properties of Zinc Composite Coatings for Mitigation of Corrosion in Coastal and Marine Zone

Deterioration of metals and alloys during service due to corrosion and wear phenomena shortens materials’ life span and structural integrity particularly in aggressive environments such as coastal and marine. This degradation also limits the use of these materials in most industrial applications. Therefore, the improvement of the quality of these materials in order to combat these challenges in industry remains critical. Surface modification techniques are employed to enhance materials’ properties to enable better performance and to extend their applications in demanding environments. Electrodeposition has been a useful method developed to improve the corrosion and mechanical properties of materials. In the present contribution, ample knowledge about electrodeposition of Zn composite/nanocomposite coatings and their characteristics are reviewed to address coastal and marine degradation of metals and alloys

Recent Advances of High Entropy Alloys: High Entropy Superalloys

This study reviews the recent technological advancements in manufacturing technique; laser surface modification and material; High Entropy Superalloys. High Entropy Superalloys are current potential alternatives to nickel superalloys for gas turbine applications and these superalloys are presented as the most promising material for gas turbine engine applications

Development of spark plasma sintered TiAlSiMoW multicomponent alloy: Microstructural evolution, corrosion and oxidation resistance

TiAlMoSiW high entropy alloy was fabricated using spark plasma sintering under different sintering temperatures. The microstructural and morphological characteristics of the alloy were investigated using X-ray diffractometry (XRD) and scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS). The mechanical and corrosion properties of the alloy were tested using diamond base indentor and potentiodynamic polarization. Thermogravimetric analysis and density measurements were used to check the thermal stability and densification of the samples. Microstructural analysis of the samples showed that the samples exhibited a bcc matrix with secondary phase precipitate of TiSi2. The microhardness was found to be subject to sintering temperature and densification with high microhardness values obtained 1000 °C and 98% densification. The presence of elements that form stable protective film were attributed to the high corrosion performance of the samples. These elements also form stable oxide scales in elevated temperatures improving the thermal stability of the alloy. Excessive oxidation was noticed to occur at temperatures above 535 °C showing that the alloy has superior thermal stability than Ti-6V-4Al. Keywords: Spark plasma sintering (SPS), High entropy alloys (HEAs), Corrosion resistant, Oxidation resistan