Mg AZ80/SiC composite bars fabricated by infiltration of porous ceramic preforms

Abstract

Semi-industrial samples of Mg AZ80/SiC/50p composites (machined bars with o.d. ϭ 80 mm and length ϭ 150 mm, having a maximum 2 vol pct of retained porosity) were successfully fabricated by pressureless, low-pressure (under overpressure of about 0.3 MPa) and moderate-pressure (under overpressure of about 0.8 MPa) infiltration. Pressureless infiltration was completed in 24 hours under the flowing atmosphere of nitrogen, whereas the moderate and low-pressure infiltrations were performed under a static atmosphere of pressurized nitrogen for 7 and 0.5 hours, respectively. The composite samples obtained by all applied infiltration paths posessed a homogeneous microstructure and superior mechanical properties as compared to the nonreinforced matrix. Due to the improved productivity of composite fabrication in comparison with the other two infiltration paths investigated in this work, the moderate-pressure infiltration process was recognized as the most competitive.

Microstructure and characteristics of the metal–ceramic composite (MgCa‐HA/TCP) fabricated by liquid metal infiltration

“…First, this process shows its superiority in the extreme uniform distribution of the ceramic reinforcements, eliminating residual porosities and interfacial reactions between the reinforcements and the matrix 9, 10. Second, this process also shows the advantageous ability of fabricating the final, or near‐final shaped composite components, minimizing the generally difficult machining of MMCs 11. Third, when suitable barriers are used to prevent the infiltration of a molten metal, it is also possible to produce selectively reinforced components, within which the metal is reinforced only where needed 9, 11…”

“…Second, this process also shows the advantageous ability of fabricating the final, or near‐final shaped composite components, minimizing the generally difficult machining of MMCs 11. Third, when suitable barriers are used to prevent the infiltration of a molten metal, it is also possible to produce selectively reinforced components, within which the metal is reinforced only where needed 9, 11…”

A review on machining of metal matrix composites using nanoparticle mixed dielectric in electro-discharge machining

“…Some methods included by the researchers are dispersion [31], stir casting [32], infiltration [33,34], squeeze casting [35], spraying [36], in-situ fabrication [37] and compo casting [38]. On the other hand, the process cannot control the process parameters and there is a certain chemical reaction between the interface of a liquid metal and reinforcement, which is not desirable.…”

Oxidation of AM60B Mg Alloys Containing Dispersed SiC Particles in Air at Temperatures Between 400 and 550 °C

“…In particular, SiC particles have been successfully incorporated in Mg [1][2][3][4], Al [5], Al-Mg [6], Al-Li [7], and Cu [8] alloys. Magnesium alloys are important metal matrices used primarily as lightweight structural materials owing to their low specific density, high modulus, and good castability and machinability.…”

“…Magnesium alloys are important metal matrices used primarily as lightweight structural materials owing to their low specific density, high modulus, and good castability and machinability. In order to combine the beneficial properties of the Mg matrix with those of reinforcing ceramics, SiC particle-reinforced magnesium, namely SiC p /Mg composites, have been developed [1,2]. The SiC p /Mg composites are of particular interest given their low density, good wear resistance, high modulus, and high strength [4].…”