A5057354428- Aluminum Alloys Composites Properties
- Aluminum Alloy Microstructure Properties
- Magnesium Alloys: Properties and Applications
- Microstructure and mechanical properties
- Metal and Thin Film Mechanics
- Experimental and Theoretical Physics Studies
- Hydrogen Storage and Materials
- Metallurgy and Material Forming
- Quasicrystal Structures and Properties
- Science Education and Pedagogy
- Engineering and Technology Innovations
- Intermetallics and Advanced Alloy Properties
- Quantum and Classical Electrodynamics
- Sports Dynamics and Biomechanics
- Thermodynamic and Structural Properties of Metals and Alloys
- Muon and positron interactions and applications
Charles University
2013-2022
Response to isochronal annealing up 440 °C of squeeze cast Mg–Y–Zn alloy and the same prepared by powder metallurgy (PM) extruded at 280 was studied resistivity microhardness measurement, differential scanning calorimetry (DSC) microstructure investigation. Electrical measured 77 K room temperature after each step. DSC measurement performed various heating rates. Transmission electron microscopy optical revealed ribbons long-period ordered structure (LPSO) 18R planar defects within grain...
A detailed characterization of phase transformations in the heat-treated commercial 7075 aluminum alloys without/with low Sc–Zr addition was carried out. Mechanical and electrical properties, thermal corrosion behavior were compared to microstructure development. The eutectic consists four parts: MgZn2 phase, Al2CuMg (S-phase), Al2Zn3Mg3 (T-phase), primary λ-Al(Mn,Fe,Si) phase. Strengthening during non-isothermal (isochronal) annealing is caused by a combination formation GP zones, η’-phase,...
Microstructure, thermal, electrical and mechanical properties of the hot-extruded hotrolled AlMnScZr alloys were studied.The resistometry microhardness together with differential scanning calorimetry measurements compared microstructure development observed by transmission electron microscopy, X-ray diffraction, backscatter diffraction.Fine subgrain or grain structure developed fine coherent Al3(Sc,Zr) particles precipitated during hot deformation subsequent cooling.The distinct resistivity...
Precipitation reactions of the Al-Zn-Mg(-Mn,Fe)-based alloys with/without Sc,Zr-addition were studied by microhardness and resistivity measurements, differential scanning calorimetry.Microstructure observation proved Zn,Mg-containing eutectic phase at grain boundaries.Positron spectroscopy confirmed presence Guinier-Preston (GP) zones in initial state.The changes curves as well heat flow are mainly caused formation and/or dissolution precipitation particles from Al-Zn-Mg system.Formation...
The effect of cold rolling (6% and 21%) on electrical, mechanical thermal properties microstructure the classical mould-cast Al-Zn-Mg alloy with without Sc,Zr-addition were studied.Samples isochronally annealed up to 460 • C. Electrical resistivity microhardness together differential scanning calorimetry measurements compared development.The initial values alloys reflect deformation degree.Distinct changes in electrical as well heat flow studied are mainly caused by dissolution Zn,Mg-rich...
The effect of cold-rolling on mechanical and electrical properties, microstructure recrystallization behaviour the AlMn, AlScZr AlMnScZr alloys was studied. materials were investigated during isothermal annealing at 300, 400, 500 550°C step-by-step quasilinear from 200°C up to 600°C with a heating rate 100 K/h followed by subsequent 600°C/5 h. Precipitation reactions studied resistometry (micro) hardness measurements. development electron microscopy backscatter diffraction examinations....
The effect of hot extrusion at 350°C on microstructure, thermal, electrical and mechanical properties the AlMnScZr alloy was studied. samples cast hot-extruded alloys were annealed from 20°C up to 600°C. Transmission scanning electron microscopy backscatter diffraction examinations specimens quenched temperatures significant resistivity changes used identify microstructural processes responsible for these changes. as well is characterized by a dispersion fine coherent Al 3 Sc and/or (Sc,Zr)...
The Mg-10 wt. % Gd and Mg-15 alloys produced by squeeze casting were solution treated at 500 °C for 8 hours subsequently naturally aged more than 2 months. Electrical resistivity of both materials measured 77 K decreases, if the are kept room temperature after quenching from temperature. This change accompanied a microhardness increase almost saturates months is caused most probably solute atoms clustering. Phase transformations changes investigated during isochronal annealing in comparison...
Abstract Demonstrating some physical principles of university physics is not always easy. The idea a simple demonstration Ampere’s law presented. induction the magnetic field around closed path ‘made visible’ by measuring voltage induced in winding surrounding path.
This work is focused on development of microstructure and properties Mg-Y-Zn Mg-Y-Nd-Zn alloys during heat mechanical treatment. In the as-cast state both exhibit almost equiaxed grains with little larger size in alloy grain boundaries decorated by different structures - long period ordered structure (LPSO) was detected eutectics Mg 3 Nd type addition. A high density stacking faults evident alloys. Both were repeatedly isochronally treated from room temperature up to 440 °C. Resistivity...
Response to isochronal annealing up 440°C was investigated in squeeze cast Mg2Y1Zn alloy and the same prepared by powder metallurgy extrusion at 280°C (PM). Electrical resistivity measurements 77 K room temperature after each step differential scanning calorimetry performed various heating rates characterized phase changes proceeding during heat treatments. Transmission electron microscopy optical revealed ribbons of a long-period ordered structure relatively high density stacking faults...
The effect of hot rolling on mechanical and electrical properties, microstructure recrystallization behaviour the AlMnScZr alloy was studied. mould-cast after at 300 °C studied during step-by-step quasilinear annealing from 200 up to 600 with heating rate 100 K/h followed by subsequent isothermal °C/5 h. Precipitation reactions were resistometry, differential scanning calorimetry hardness measurements. Transmission electron microscopy backscatter diffraction examination specimens quenched...
Al-based alloys are very preferred for automotive manufacture to produce lightweight vehicles. The positive effect of Sc,Zr-addition on the mechanical properties in is generally known. Microstructure, mechanical, electrical and thermal conventionally cast homogenized Al–Zn–Mg alloy with without during isochronal annealing were studied. resistometry microhardness together differential scanning calorimetry measurements compared microstructure development that was observed by optical microscopy...
The positive effect of Sc,Zr-addition on mechanical properties in Al-based alloys preferred for automotive manufacture to produce lightweight vehicles is generally known. Microstructure, mechanical, electrical and thermal the conventionally cast homogenized (475 °C/60 min) Al-5.4wt.%Zn-3.1wt.%Mg-1.5wt.%Cu (7075) Al-5.2wt.%Zn-3.0wt.%Mg-1.4wt.%Cu-0.2wt.%Sc-0.1wt.%Zr (7075-ScZr) during isochronal annealing were characterized. Precipitation reactions studied by microhardness, resistivity...
Newton’s laws are essential for understanding causes and description of mechanical motion. Great attention is paid to them during physics education. Unfortunately, many students, not only in high school, but also undergraduates, can recite do understand their essence. Therefore, it useful demonstrate different experiments the classroom order support strengthen understanding. Less traditional demonstrating be performed using Poggendorff’s scales (also known as fall device). This article...