M.N. Masri, Z.M. Yunus, A.R.M. Warikh and A.A. Mohamad
The purpose of this paper is to investigate the electrical conductivity and corrosion protection properties of a conductive coating composed of epoxy resin and carbon black in a…
Abstract
Purpose
The purpose of this paper is to investigate the electrical conductivity and corrosion protection properties of a conductive coating composed of epoxy resin and carbon black in a sodium chloride (NaCl) solution.
Design/methodology/approach
The conductive coating was prepared by combining epoxy resin, hardener, and carbon black. The electrical conductivity of the paint was studied with a DC current‐voltage meter and field emission scanning electron microscopy. The corrosion protection properties of the paint were characterized by open circuit potential measurements and electrochemical impedance spectroscopy.
Findings
The highest conductivity observed was 4.23×10−4 Scm−1 for the coating containing 20 wt% carbon black. The coating protected mild steel in a 3.0 percent NaCl solution for up to five days.
Originality/value
The results shown in this paper provide an insight into conductive paint and corrosion protection for future industrial applications and development.
Details
Keywords
Yuchen Xiao, Huiyi Tang, Hehe Zhang, Xiaoling Yang, Ling Sun, Yong Xie, Baoan Wu, Baifeng Luan, Weidong Xie and Xinnan Cai
The purpose of this paper is to develop high-performance Au-coated Ag alloy wires (ACAA wires) and demonstrate the effect of Au coating layers on the bonding performance and…
Abstract
Purpose
The purpose of this paper is to develop high-performance Au-coated Ag alloy wires (ACAA wires) and demonstrate the effect of Au coating layers on the bonding performance and oxidation resistance for stable and reliable electronic packaging applications.
Design/methodology/approach
ACAA wire with a diameter of approximately 25 µm and Au layer thickness of approximately 100 nm were prepared by the continuous casting, plating and wire drawing method. The bonding performance of the ACAA wires were studied through bonding on 3,535 chips. The oxidation resistance of ACAA wires and Ag alloy wires (AA wires) were comparatively studied by means of chemical oxidation tests, accelerated life tests and electrochemical tests systematically.
Findings
ACAA wires could form axi-symmetrical spherical free air balls with controllable diameter of 1.5∼2.5 times of the wire diameter after electric flame-off process. The ball shear strength of ACAA wire was higher than that of AA wires. Most importantly, because of the surface Au coating layer, the oxidation resistance of ACAA wires was much enhanced.
Research limitations/implications
ACAA wires with different lengths of heat affected zone were not developed in this study, which limited their application with different loop height requirements.
Practical implications
With higher bonding strength and oxidation resistance, ACAA wires would be a better choice than previous reported AA wire in chip packaging which require high stability and reliability.
Originality/value
This paper provides a kind of novel ACAA wire, which possess the merits of high bonding strength and reliability, and show great potential in electronic packaging applications.
Details
Keywords
Zhenxing Ren, Daowu Yang, Jun Liu, Yong Ma, Zhongtang Huo and Shaochang Zheng
The purpose of the paper was to design an anti-corrosion system that combined conductive coatings with cathodic protection for a 500-kV substation ground grid, and provide a basis…
Abstract
Purpose
The purpose of the paper was to design an anti-corrosion system that combined conductive coatings with cathodic protection for a 500-kV substation ground grid, and provide a basis for the anti-corrosion construction of the installation.
Design/methodology/approach
The study took the Shaoguan 500-kV substation grounding grid as the research object. The anti-corrosion performance of KV conductive coatings on grounding metal was researched. In parallel, the alkalinity of substation soil was evaluated according to the German DIN50929 Standard, and the combined protection system comprising conductive coatings and impressed current cathodic protection was designed.
Findings
KV conductive coatings, that have resistance to acids, alkalis and salts, can effectively slow down the corrosion rate of the grounding grid. The investigation also provided the outline design, installation, construction requirements and monitoring methods for the 500-kV substation grounding grid.
Originality/value
This report contains some guiding significance for anti-corrosion engineering of 500-kV substation grounding grids.