In November I performed some microhardness measurements on melt-spun ribbons with different loading rates. I tried to gather data I have obtained so far and analyze them to set research plan for nearest months. In this month three new melt spun ribbons with W, Hf and Nb addition were prepared. Additionally two new ingots were cast into steel mould. During November I was also preparing for the joint seminar in Dresden planned for the first part of December.

Continuation of the molecular dynamic simulation for liquid binary alloys Al-Zn, Al-Li using EOPP and MEAM potential for modelling the viscosity, density. Attempt to find the interatomic potential for Zn in order to application for liquid Al-Zn alloy. In case of Al-Li alloy, many variants were used in order to predict physical properties.
EMF measurement for application to liquid ternary Al-Zn-Li alloy. Analysis of the experimental results. Ab initio molecular dynamic study.

Samples polished grit paper the final of 1200, and then polished the diamond pastes (powder with a diameter of 6, 3 and 1 micron). The samples to be further polished for microscopic examination using a colloidal silica having a particle size 0.06 microns, and then digested with the alcohol solution consisting of 10 ml of acetic acid + 10 ml water + 70 ml of a 4% solution of picric acid in ethanol. For samples destined for final polishing micro-hardness measurements were carried out on the diamond grit paste 0.25 microns. Photos morphology of the samples was performed on an optical microscope Leica DMIRM. The measurements were made using Knoop hardness with a load of 0.1 kg at 2500 Tukon hardness tester using the guidelines of ISO 4545. Two series of measurements were made covering the entire wall thickness (in the direction of TD). For one of them, the longer diagonal footprint was always parallel and the other perpendicular to the RD.

During last couple of weeks samples of KoBoed earlier zinc were analyzed by means of EBSD technique in SEM. As pointed before samples were held in liquid nitrogen temperature prior to metallographic preparation and inspection. Crystal Orientation maps from transverse sections revealed microstructure similar to that observed earlier in 'fresh samples'. No large grains and no fine grains arranged into intergranular lines have been observed. Mean grain size is close to 15 micrometers and some grains are slightly elongated. Some characteristic arrangement of grains forming bands can be observed which is similar feature to those observed also in KoBo extruded titanium in Transverse section.
Lack of large grains and subgrain features further support hypothesis of room temperature recrystallization or healing processes in KoBo extruded zinc.

The article send to 'Materials Science Forum':

'Early stages of recrystallization in ECAP-deformed AA1050 alloy
investigated by SEM orientation mapping'

Jagoda Poplewska, Henryk Paul, Katarzyna Berent

Keywords: nucleation & recrystallization, AA1050 alloy, ECAP, second phase particles, orientation mapping;

Abstract
Early stages of recrystallization were observed for the technical purity aluminium
alloy (AA1050). The samples were severely deformed by equal channel angular pressing and then annealed to obtain the state of partial recrystallization. The nucleation of new grains and the changes in ‘density’ of low- and high- angle boundaries were analysed using scanning electron microscopy equipped with high resolution EBSD system. After deformation in six passes along route A the alloy contained a structure of flat grains. On annealing, the structure coarsened and got transformed into nearly equiaxed grains by both discontinuous and continuous recrystallization. A particular role in the rise of nuclei and the structure spheroidization is attributed to migration of low-angle boundaries.