My research in October:


The article entitled "Investigation of structures in as-cast alloys from the Mg-Zn-Ca system"
was sent to Achives of Materials and Metallurgy

Here you can read abstract:

Alloys of nominal composition Mg-3Zn-xCa (x = 0, 0.2, 0.5, 0.7, 1.0, 1.3) wt.% have been prepared by resistance melting and casting into graphite mould under argon atmosphere. All investigated alloys have revealed (Mg) dendritic microstructures with intermetallic phases distributed in interdendritic spacing. The Mg4Zn7 has been identified as the main phase which coexists with (Mg) in the Mg-Zn alloy. Calcium addition causes the formation of ternary Ca2Mg6Zn3 hexagonal phase, denoted also as Ca3MgxZn15-x. The increase of Mg/Zn ratio from 0.59 in Mg-3Zn-0.2Ca wt.% alloy to 2.72 in Mg-3Zn-1.3Ca wt.% alloy in this phase is connected with an increase in the lattice parameters. The microhardness of the Ca containing alloys increases up to 67 HV (for the alloy containing 1.3 wag.% Ca) compared to the 50 HV for Mg-3Zn wt.% alloy.

In October I’ve studied the electrodeposition process. I lead the process of potentiostatic deposition of Zn-Mo alloy layers, on the steel and copper surfaces, from stable homogeneous Zn(II)-Sn(II)-Mo(VI) and Zn(II)-Mo(VI) citrate baths, in the slightly acid range (pH about 5), with different concentration of metals and citrate ions. The measurements were performed in a three-electrode cell or galvanostatically in a two-electrode cell in coulostatic condition, by means of potentiostat PGSTAT302N.

Management of the molecular dynamic simulation for liquid Al-Zn alloys in order to model the transport properties using Yukawa and EOPP potential. Random mixing and PBC condition was used to simulate the viscosity and diffusion coefficient.

Little did we know with respect to linearity of bevavior of the martensite start temperature in the particular valence electron range, which is somewhat omitted in the literature on this subject. Therefore in order to shed more light on this intriguing phenomena new set of alloys was prepared. The alloys were homogenised at 1000 degC for 6 hours. They were sealed in quartz ampules beforehand but unfortunately while in the oven three of the tubes broke. The alloys were therefore subjected to chemical analysis to estimate possible changes in composition and the effects of oxidation. The analysis performed in the bulk of the materials showed that no major compositional changes occured.

The object of study was a commercial pipe magnesium Mg 3% Al 1% Zn 0.2% Mn (AZ31), hot pressed out at 430 ° C with a degree of deformation equal 9th Tube having an initial wall thickness of 4.5 mm and a diameter of 20 mm was then subjected to the process of rolling pielgrzymowego plunger. Before rolling, the material is heated to a temperature of 200 ° C. During the rolling deformation gradually increased up to approximately 55% reduction in cross-section. It has been observed that above 51% reduction of the deformation section the material began to crack and crumble. Therefore selected for further study of the deformation of the material up to 50%. Texture layers lying in the middle of the pipe wall thickness (Fig. 1) was determined on the basis of incomplete pole figures reflections (0001), (​​10-10), (10-11), (10-12) and (11-20) are registered dyfrakometru using D8 Discover X-ray, using radiation CoKα series. Measurements were made in the measuring grid równokątowej of α: 0 - 75 ° with a step Δα = 5 °. During the measurements used mikrokapilarę limiting the measurement area of approximately 3 mm, with the center of the area to coincide exactly with the axis of the tube. LaboTexTM using software, using the method of ADC was calculated orientation distribution function. Research metalograficznie and microhardness measurements were performed on longitudinal zgładach (RD-TD plane parallel to the longitudinal axis of the pipe). In this figure also shows the accepted frame of reference.