My activities in February:

During this month I performed extensive literature overview on hardening behaviour of Mg-Zn-Ca alloys.

A bit of history:

The first systematic attempt to characterize hardening behaviour in Mg-Ca-Zn alloys was performed by Nie and Muddle[1997]. The researchers investigated the binary Mg-1 wt% Ca alloy and ternary Mg-1Ca-1Zn wt% alloy. The age hardening response of the binary alloy is not very significant. However, by adding zinc the aging response is significantly enhanced and the time to the peak hardness is shortened. The beneficial effect of zinc in enhancement of the aging response of the binary Mg-Ca alloy was also confirmed by Gao et al. [2005].

In the month of February I focused on some writing assignments. Firstly, I have prepared a paper for the occasion of Advanced Materials and Technologies conference, entitled: „ Characterization of reaction products of liquid Al and Mg3N2”. Secondly, I have written an abstract for a symposium: „Materials Science for Industry” with a following title: „Aluminium alloy nano-composites reinforced with AlN particles”.

In order to determine the type and size of the residual stress in the initial and deformed state we applied X-ray diffraction. Stress and texture measurement were done on the lateral surface of the pipe, but due to geometrical conditions, the most reliable result of the stress values were obtained for the position of the tube axis in the plane of diffraction. The difficulty in the analysis of deformation by sin Ψ ² proved to be varied by texture in both samples. Diffraction elastic constants for both samples were calculated on the basis of the orientation distribution functions. Residual stresses were calculated based on the assumptions of the Reuss model.
We derived the full form of the tensor of plastic and stiffness and elastic constants has been developed based on these models in order to enable the transformation tensor by rotation in accordance with the Einstein summation convention. In order to confirm the validity of these operations Young's surface was calculated , which is a spatial graph of the inverse element of S3333 stiffness tensor in orientation of the unit cell of the crystal.

In February I’ve started the XRD analysis of chosen Zn-Mo Alloy layers.
XRD analysis does not show the presence of molybdenum oxides, neither metallic molybdenum nor other molybdenum compounds (ZnMo7 and ZnMo22). It was found that only the hexagonal system of the Zn phase is present in the deposits The lack of any peak connected with molybdenum, regardless of the amount in the deposit, suggests that it has a nanometric or amorphous structure. The XRD studies have to be continued.

MEAM potential modelling for Al-Li alloys. Physical, dynamical et structural properties simulation in view of a new formulated MEAM potential. Imposing ternary interaction on MEAM potential and DFT study for binary alloys.