Development of Pumice Reinforced Magnesium Based Composites


Sevin D., Kösedağ E., Kelen F., Aydoğmuş T.

International Pumice and Perlite Symposium, Bitlis, Turkey, 4 - 06 November 2021, pp.12-13

  • Publication Type: Conference Paper / Summary Text
  • City: Bitlis
  • Country: Turkey
  • Page Numbers: pp.12-13
  • Van Yüzüncü Yıl University Affiliated: Yes

Abstract

In the present study, it was investigated whether pumice powder, which is an unusual (non-traditional)

reinforcement material for metals, can be used in the production of magnesium-based composites. For this

purpose, magnesium matrix composite materials reinforced with pumice were produced by hot pressing method.

The dimensions of the starting magnesium and pumice powders were smaller than 45 μm. The pumicemagnesium

powder mixtures containing 10% reinforcement by volume were subjected to hot pressing under

protective argon gas for 1 hour under 50 MPa pressure at 550 °C in graphite molds. Since thermodynamic

calculations show that it is possible to reduce SiO2by magnesium in completely solid state at 550 °C, it is aimed

to produce Mg2Si and MgO reinforced magnesium matrix composite materials by in-situ method as a result of

the chemical reaction of pure magnesium with SiO2 in the pumice. The density of the produced composite

materials was determined by the Archimedes’ method, the phases present in the microstructure were determined

by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyzes. The hardness of the produced

composite material and that of pure magnesium were determined by Micro-Vickers hardness measurements. As

a result of XRD and SEM analysis, it was observed that there were magnesium, Mg2Si, MgO, and oxide phases

present in the raw pumice powders in the composite microstructure. It was determined that the hardness of the

matrix phase of the composite material, which has a density value close to the full density, increased approximately 26% compared to pure magnesium. In the light of the results obtained, it is concluded that pumice

can be used as a reinforcement material in the production of magnesium-based composite materials, considering

its low density and low cost, and that the developed composite materials can be used in industrial applications

such as automotive and aerospace where low density is an important parameter.

Keywords: Magnesium matrix composites, Pumice, Hot pressing, Microstructure, Mg2Si, MgO