Wyniki wyszukiwania - BazTech

1

Precise Orientation Control of Single Crystalline NiMnGa-Based Alloys by in-situ EBSD Analysis

Szewczyk Arkadiusz, Faryna Marek, Wójcik Anna, Maziarz Wojciech, Chulist Robert

Archives of Metallurgy and Materials

|

2023

|

Vol. 68, iss. 3

1171--1175

EN

The article presents a precise method for the orientation process of NiMnGa-based single crystals. For this method, a scanning electron microscope equipped with an EBSD camera and a heating stage allowing temperatures exceeding 873 K was used. The orientation process was carried out in both the high-temperature austenite phase and in the room-temperature martensite phase. The facilities allowed for determining the orientation of a single grain of austenite at elevated temperatures as well as the orientation of particular martensitic variants at room temperature. A practically perfect cubic orientation was obtained in the austenitic case with a deviation of about 1° while the samples oriented in the martensitic phase deviated from the desired orientation by 4.5-5.2°. Additionally, the training process of single crystals was carried out in order to show the influence of the orientation process on twinning stress.

2

Influence of Hot Pressing on the Microstructure of Multi-Layered Ti/Al Composites

Kowalski Wojciech, Paul Henryk, Petrzak Paweł, Maj Łukasz, Mania Izabela, Faryna Marek

Archives of Metallurgy and Materials

|

2021

|

Vol. 66, iss. 4

1149--1156

EN

Metal-intermetallic layered (MIL) composites attract considerable attention due to their remarkable structural and ballistic performance. This study aimed to develop a Ti/Al-based multilayered MIL material by adding ceramic powders, since they can improve the composite’s impact resistance. To this end, an experiment was conducted which a stack of alternating Ti and al sheets bonded by hot pressing; Ti/Al multilayers containing additional layers of Al2O3 and SiC powders were also produced. The samples obtained were examined using electron microscopy techniques. The clads’ mechanical properties were investigated using a Charpy hammer. In the reaction zone, only one intermetallic phase occurred: the Al3Ti phase. The model with an additional Al2O3 layer showed the highest impact energy. none of the Ti/Al clads broke during the Charpy impact test, a result proving their high ductility.

3

Mikroskopia dwuwiązkowa w badaniach właściwości materiałów ceramicznych od 3D EBSD do FIB-DIC

Faryna Marek

Szkło i Ceramika

|

2020

|

R. 71, nr 1

20--21

4

Superplastic deformation of Mg–9Li–2Al–0.5Sc alloy after grain refinement by KoBo extrusion and cyclic forging

Dutkiewicz Jan, Kalita Damian, Maziarz Wojciech, Faryna Marek

Archives of Civil and Mechanical Engineering

|

2020

|

Vol. 20, no. 4

343--353

EN

The quaternary Mg–9Li–2Al–0.5Sc alloy (in wt%) was prepared from pure components. After homogenization, the alloy was subjected to severe plastic deformation by KoBo extrusion and cyclic forging leading to grain refinement in the range of 0.5–2 µm of hexagonal close-packed (HCP) α phase. Deformed alloys showed high ultimate tensile strength near 200 MPa and good elongation in the range 30–40% at room temperature (RT). Large elongations close to 200% were obtained during the tensile test at a temperature of 200 °C. Deformed samples showed the presence of multiple voids confirming grain boundary sliding mechanism of deformation. Twins on {101-2} planes were identified using electron backscatter diffraction analysis, being in a good agreement with the earlier observation of Mg–Li and Mg–Sc alloys. Intermetallic phases such as cubic MgSc were identified in deformed alloys mostly within HCP α phase, whereas HCP MgSc2 particles were observed within body-centered cubic (BCC) β phase. Intermetallic phases were responsible for RT strengthening of alloys and slightly lower tensile elongation during superplastic deformation. Formation of the HCP α phase was observed within the BCC β phase in tensile deformed alloys. Atomic-level nucleation of HCP phase within the β phase was identified by the use of high-resolution transmission electron microscopy technique.