Properties of AgSnO2 Contact Materials Doped with Different Concentrations of Cr

Abstract

As an important component carrying the core function and service life of switching appliances, the selection and improvement of electrical contact materials is of great significance. AgSnO2, which is non-toxic, environmentally friendly and has excellent performance, has become the most promising contact material to replace AgCdO. However, it has deficiencies in machinability and electrical conductivity. The property of AgSnO2 contact material was improved by doping element Cr. The relationship between the mechanical and electrical properties of AgSnO2 contact materials and doping concentrations were investigated and analyzed by simulation and experiment. Based on the first principle, the elastic constants of supercell models Sn1−xCrxO2 (x = 0, 0.083, 0.125, 0.167, 0.25) were calculated. The results show that the material with a doping ratio of 25% is least prone to warp and crack, and the material with a doping ratio of 12.5% has the best toughness and ductility and the lowest hardness, which leads to molding and is subsequently easier to process. The Cr-doped AgSnO2 contacts with different doping proportions were prepared by the sol–gel and powder metallurgy method. Additionally, their physical performance and electrical contact properties were measured in experiments. The results show that the doped SnO2 powders prepared by the sol–gel method realize integration doping, which is consistent with the crystal model constructed in the simulation calculation. Sn0.875Cr0.125O2 has lower hardness, which is beneficial to process and form. Doping helps to stabilize the arc root, inhibit the ablation of contact by arc, reduces arc duration and arc energy, improves the resistance to arc erosion of AgSnO2 contact material, and makes electrical contact performance more stable. The contact material with a doping concentration of 16.7% has the best arc erosion resistance.

Impact of digital financial innovation on financial system development in Common Market for Eastern and Southern Africa (COMESA) countries

“…The dynamic divergence in the short run is corrected 74% of the time. The PMG result reveals among our measures of digital financial innovation that ATM, POS, MP and MB are significant and contribute positively to financial system development in the long run, and, as such, supported the evidence provided by Tahir et al (2018), Nzioka and Kamakia (2017), Wang et al (2022), Qamruzzaman and Wei (2019), Lee et al (2020) and Aayale (2017) who at the different time studied the relevance of various financial innovation or technology measures in predicting financial system performance. In like manner, further evidence from our findings suggests that a percentage increase in ATM, POS, MP and MB results in a 52%, 43%, 55% and 50% increase in financial system development in COMESA in the long run, respectively, which contradicted the findings of Mugane and Ondigo (2016) which argued that financial innovation does not significantly contribute to the financial performance of commercial banks in Kenya.…”

“…But, more is the fact that most measures of digital financial innovations are positive and significantly related to financial system development. This finding supports the evidence from Duygun et al (2013), Tahir et al (2018, Nzioka and Kamakia (2017), Wang et al (2022), Qamruzzaman and Wei (2019) and Lee et al (2020) studies. However, some of the measures found negative in the long run could be caused by factors such as the lack of literacy programs inherent in developing countries that will guarantee that people apply comprehensive financial decisions and choose financial products which benefit their needs as well as how to use associated channels.…”

“…Findings from panel ARDL confirmed the positive association between financial innovation and financial inclusion, which was observed both in the long run and short run. Wang et al (2022) examined the impacts of financial innovation on banks' profitability in Africa. The study employed the dynamic panel data method and GMM estimations via a panel data regression model.…”

“…Many studies that attempted to explain the relationship were country-specific studies as earlier discussed. Few cross-country studies on financial innovation impact were particularly interested in either the banking system, stock market and economic growth (see Wang et al, 2022;Aayale, 2017), while other studies are on financial inclusion, financial innovation, incorporating financial AJEB 8,1 development and remittance inflows concentrated in South Asian and European countries (see Qamruzzaman and Wei, 2019;Beck et al, 2016).…”

Preparation and Performance of Biodegradable Poly(butylene adipate-co-terephthalate) Composites Reinforced with Novel AgSnO2 Microparticles for Application in Food Packaging

“…Previously, the PBAT material was incorporated with some nanoparticles, including TiO 2 [ 19 ], ZnO [ 20 ], Ag 2 O [ 21 ], SiO 2 [ 22 ], SnO 2 [ 23 ], MgO [ 24 ], and MgO/Ag [ 25 ]. AgSnO 2 is the most preferred metal oxide nanofillers because of its unique characteristics, such as non-toxicity, large surface area, high mechanical strength, and crystallization-inducing abilities [ 26 , 27 , 28 ]. On the other hand, there are two issues with the development of AgSnO 2 materials.…”