Microstructure and Mechanical Behavior of Al-Mg Composites Synthesized by Reactive Sintering

Abstract

Lightweight metal matrix composites are synthesized from elemental powder mixtures of aluminum and magnesium using pressure-assisted reactive sintering. The effect of the reaction between aluminum and magnesium on the microstructure and mechanical properties of the composites due to the formation of β-Al3Mg2 and γ-Al12Mg17 intermetallics is investigated. The formation of the intermetallic compounds progressively consumes aluminum and magnesium and induces strengthening of the composites: the yield and compressive strengths increase with the increase of the content of intermetallic reinforcement at the expense of the plastic deformation. The yield strength of the composites follows the iso-stress model when the data are plotted as a function of the intermetallic content.

ON MECHANICAL BEHAVIOUR OF PRESSURE-ASSISTED, SINTE RED Al-Mg COMPOSITE

“…Lightweight materials like Aluminium (Al)-Magnesium (Mg) composite are in special attraction of automotive and aerospace industry [1][2][3][4]. Al-Mg composite combines excellent density of Mg (1.73 g/cm 3 ) with Al corrosion resistance (density of Al is 2.7 g/cm 3 ) [2,4].…”

“…Particulate reinforced metal matrix composites (MMCs) have isotropic properties, easier processing route than other metal matrix composites and they are cheaper than other metal matrix composites [3]. MMCs (with various reinforcements) can be produced by casting, metal infiltration, friction stir welding or powder metallurgy [3].…”

“…Particulate reinforced metal matrix composites (MMCs) have isotropic properties, easier processing route than other metal matrix composites and they are cheaper than other metal matrix composites [3]. MMCs (with various reinforcements) can be produced by casting, metal infiltration, friction stir welding or powder metallurgy [3]. Powder metallurgy has an advantage in controlling matrix and reinforcement properties like shape and size of the reinforcement particles, particle distribution and volume fraction in the matrix [3].…”

“…MMCs (with various reinforcements) can be produced by casting, metal infiltration, friction stir welding or powder metallurgy [3]. Powder metallurgy has an advantage in controlling matrix and reinforcement properties like shape and size of the reinforcement particles, particle distribution and volume fraction in the matrix [3]. However, an inherent characteristic of powder metallurgical components is porosity that influences mechanical behaviour [5][6][7].…”

“…Pressure-assisted reactive sintering was used to produce many (also non-metal) composites such as ZrB2-SiC-ZrC [20], B4C/Li2O-Al2O3-SiO2 [21], Al-Si [22], ZrB2-SiC-ZrO2 [23], TiC/Ti3SiC2 [24] or reinforced Al matrix composites [3] [25]. Depending on material and processing conditions, porosity varied between 2.4% [21] and 26% [24].…”