To better understand the effect of the components of molten 2219 Al alloy on the hydrogen content dissolved in it, the H adsorption on various positions of alloying element clusters of Cu, Mn and Al, as well as the inclusion of Al₂O₃, MgO and Al₄C₃, were investigated by means of first principles calculation, and the thermodynamic stability of H adsorbed on each possible site was also studied on...

Surfaces made of copper or its alloys have strong antimicrobial properties against a wide variety of microorganisms. However, the molecular mode of action responsible for the antimicrobial efficacy of metallic copper is not known. Here, we show that dry copper surfaces inactivate Candida albicans and Saccharomyces cerevisiae within minutes in a process called contact-mediated killing. Cellular ...

We report results of our experimental and theoretical studies on the oxidation of Cu-Au alloy surfaces, viz., Cu3Au(111), CuAu(111), and Au3Cu(111), using hyperthermal O2 molecular beam (HOMB). We observed strong Au segregation to the top layer of the corresponding clean (111) surfaces. This forms a protective layer that hinders further oxidation into the bulk. The higher the concentration of A...

In this study, beryllium-copper alloy was subjected to around -150° F for cold treatment and to around -300° F for cryogenic treatment and the effects of these cold and cryogenic treatments on the machinability of beryllium-copper workpieces in electro discharge machining have been investigated. Experimental results showed about 20-30 % increase in material removal rate of cold and cryogenic tr...

Gold alloys with Cu contents of 10 mass%, 20%, and 30% were used for morphological observation of porous surface structures after heating at 800 degrees C in air followed by pickling with acid solution. With increasing Cu content in the gold alloy, the internal oxidation zone became well-developed in the alloy matrix. The mechanism by which a porous structure was formed on the surface of a gold...

The possibility of using die steels (4Kh3N5М3F and 4Kh4N5М4F2) with adjustable austenitic transformation during operation for a wide range operating temperatures (below the critical point A 1 above 3 ) is shown hot deformation M1 copper (up to 630 °С) МNZh5-1 copper-nickel alloy (900-950 °C) increased service life. During МNZh5-1, life matrices made steel 4Kh3N5М3F was increased, compared 3Kh3М...