Song Tang, Xiaowen Chen, Defen Zhang, Wanlin Xie, Qingzheng Ran, Bin Luo, Han Luo and Junwei Yang
The purpose of this study is to investigate the influence of varying concentrations of nano-SiO2 particle doping on the structure and properties of the micro-arc oxidation (MAO…
Abstract
Purpose
The purpose of this study is to investigate the influence of varying concentrations of nano-SiO2 particle doping on the structure and properties of the micro-arc oxidation (MAO) coating of 7075 aluminum alloy. This research aims to provide novel insights and methodologies for the surface treatment and protection of 7075 aluminum alloy.
Design/methodology/approach
The surface morphology of the MAO coating was characterized using scanning electron microscope. Energy spectrometer was used to characterize the elemental content and distribution on the surface and cross section of the MAO coating. The phase composition of the MAO coating was characterized using X-ray diffractometer. The corrosion resistance of the MAO coating was characterized using an electrochemical workstation.
Findings
The results showed that when the addition of nano-SiO2 particles is 3 g/L, the corrosion resistance is optimal.
Originality/value
This study investigated the influence of different concentrations of nano-SiO2 particles on the structure and properties of the MAO coating of 7075 aluminum alloy.
Details
Keywords
Xiaowen Chen, Wanlin Xie, Song Tang, Meng Zhang, Hao Song, Qingzheng Ran and Defen Zhang
The purpose of this study is to examine the impact of MoS2 on the microstructure and characteristics of micro-arc oxidized (MAO) ceramic coatings created on ZK60 magnesium alloy…
Abstract
Purpose
The purpose of this study is to examine the impact of MoS2 on the microstructure and characteristics of micro-arc oxidized (MAO) ceramic coatings created on ZK60 magnesium alloy through the addition of varying concentrations of MoS2 particles to the electrolyte, aiming to enhance the corrosion resistance of magnesium alloy.
Design/methodology/approach
The surface morphology, roughness and phase composition of the coatings were analyzed using scanning electron microscopy, a hand-held roughness tester and an X-ray diffractometer, respectively, and the corrosion resistance of the MAO coatings prepared by the addition of different contents of MoS2 particles was tested and analyzed using an electrochemical workstation.
Findings
The results demonstrate that MoS2/MgO composite coatings have been successfully prepared on the surface of magnesium alloys through micro-arc oxidation. Furthermore, the corrosion resistance of the ZK60 magnesium alloy prepared with the addition of 1.0 g/L MoS2 was the best compared to the other samples.
Originality/value
MoS2 particles were able to penetrate the coatings successfully during the micro-arc oxidation process, acting as a barrier in the micropores to prevent the corrosion medium from touching the surface, thus improving the corrosion resistance of the sample. The electrochemical workstation was used to study the corrosion resistance of the MoS2/MAO coating on the ZK60 magnesium alloy.
Details
Keywords
Yu Chen, Xiaoning Zhu, Xueli Xiong, Cen Zhang and Jiashun Huang
Corporations, as key contributors of greenhouse gas emissions, have been increasingly scrutinized by governments and stakeholders. Corporations have been asked to disclose their…
Abstract
Purpose
Corporations, as key contributors of greenhouse gas emissions, have been increasingly scrutinized by governments and stakeholders. Corporations have been asked to disclose their carbon-related information. This study investigates public corporate carbon disclosure, an imperative communication channel between firms.
Design/methodology/approach
This study uses generalized estimation equation models with a longitudinal panel data of 311 listed firms in the China A-share stock index from 2010 to 2020. This study collected firm-level data from the Carbon Disclosure Project survey, the China Stock Market and Accounting Research, and the National Economic Research Institute of China. Stata was used as the primary statistic software in empirical analyses.
Findings
This study finds that compared to state-owned enterprises (SOEs), private firms are more willing to disclose carbon information under legitimate environmental pressure, and firms in highly distorted factor-markets are reluctant to disclose carbon information. This study finds that factor-distortion markets further moderate ownership and lead private firms in highly distorted factor-markets to behave like SOEs by significantly reducing their carbon disclosures.
Originality/value
This study intends to contribute to the corporate carbon disclosure literature by adding important institutional determinants to the conversation in the context of China.