Related Experiment Video
Updated: Sep 6, 2025
07:36
Experimental Procedure for Warm Spinning of Cast Aluminum Components
Published on: February 1, 2017
9.6K
Effect of Magnesium Powder Application on the Microstructure and Properties of Rods Extruded by the Forward-Backward
Anita Olszówka-Myalska1, Patryk Wrześniowski1, Paweł Ostachowski2
1Faculty of Materials Engineering, Silesian University of Technology, Krasińskiego 8, 40-019 Katowice, Poland.
Materials (Basel, Switzerland)
|June 24, 2022
Summary
KOBO extrusion significantly alters pure magnesium properties based on its initial form. Sintered magnesium powder exhibited enhanced mechanical properties and refined microstructures after severe plastic deformation.
Area of Science:
- Materials Science
- Metallurgy
- Mechanical Engineering
Background:
- Severe plastic deformation (SPD) methods like KOBO extrusion are known to enhance metal properties.
- The influence of magnesium's initial form (powder vs. cast) on KOBO extrusion outcomes is not well-understood.
- Understanding these effects is crucial for metal powder processing, recycling, and composite fabrication.
Purpose of the Study:
- To investigate the effects of KOBO extrusion on pure magnesium in different initial forms: cold-compacted powder, sintered powder, and cast ingots.
- To characterize the microstructural and mechanical property changes induced by KOBO extrusion.
- To analyze the role of the initial material form on the observed phenomena and decohesion mechanisms.
Main Methods:
- KOBO extrusion was used to process pure magnesium rods (8 mm diameter, 400 mm length).
- X-ray diffraction (XRD) analyzed changes in crystallite size and orientation.
- Microstructural analysis, porosity, hardness, tensile, and compressive strength tests were performed.
- Decohesion mechanisms were analyzed based on the starting material form.
Main Results:
- KOBO extrusion induced significant microstructural and property differences between materials derived from powder and cast forms.
- α-Mg grain refinement and refinement of surface-derived MgO into fine particles surrounded by magnesium were observed.
- The refined MgO particles formed oriented bands, enhancing mechanical properties and altering decohesion mechanisms.
- Sintering of magnesium powder under pressure was found to be necessary before KOBO extrusion.
Conclusions:
- The initial form of magnesium critically influences the outcomes of KOBO extrusion.
- KOBO extrusion refines both the magnesium matrix and embedded oxide particles, leading to improved mechanical performance.
- The study highlights the importance of pre-sintering magnesium powder for successful KOBO extrusion and property enhancement.
