A novel approach for dynamic compaction of Mg–SiC nanocomposite powder using a modified Split Hopkinson Pressure Bar

Abstract

In this paper, fabrication and characterisation of Mg-SiC nanocomposite are investigated. Micrometre-sized Mg powder with the different volume fraction of SiC nano particles were dynamically compacted using a modified Split Hopkinson Pressure Bar. Moreover, the compaction process was simulated using AUTODYN commercial software to demonstrate that the stress in the powder sample was sufficient for consolidation. To achieve the best quality samples, the effects of lubrication and compaction velocity on dynamic compaction process were initially studied by experiment. It was observed that the temperature of 450°C and the compaction velocity of 15.5 m/s led to the best samples with relative density more than 99%. The effects of reinforcing phase content on the relative density, micro-hardness, and compressive behaviour of the compacted samples along with their microstructures were investigated. The results showed that the micro-hardness and the compressive strength of the samples fabricated at 450°C increased about 70% and 50%, respectively.

Simultaneous effects of strain rate and temperature on mechanical response of fabricated Mg–SiC nanocomposite

“…The first part of the investigation 14 dealt with production of the nanocomposite samples using DH testing device at different temperatures. The second part of the investigation 15 was related to fabrication of the nanocomposites using Hopkinson bar testing apparatus at a single temperature. The main objective of this work is to study the effect of compaction temperature on density, microhardness, and compaction behavior of samples produced by high-rate consolidation technique using a split Hopkinson pressure bar (SHPB).…”

The effect of particle size on microstructure, relative density and indentation load of Mg-B4C composites fabricated at different loading rates

“…22 The compactions are performed using a die with sufficient rigidity. More details about design and material of the die can be found in Rahmani et al 10 All compaction processes were carried out at temperature of 450 C using a 1200 W ceramic heating element. This temperature is close to the sintering temperature of magnesium which is 0.75 of its melting point.…”

“…16 Sample's density was measured using the Archimedes principle. 10 In this study, the specimens fabricated under quasi-static loading are shown by QS, the samples produced using drop hammer are denoted by DH and the samples fabricated using Split Hopkinson bar are specified by SHB. The flowchart of the procedure of nano/microcomposite fabrication and test program is shown in Figure 3.…”

“…The presence of hard particles in a soft and deformable matrix reduces the composites compatibility. 10 By increasing the hard nanoparticles volume fraction, porosity increases, and therefore relative density decreases. This can also be due to clustering of nanoparticles.…”

“…Faruqui et al 7 used underwater shockwaves to fabricate Mg-SiC composite. Majzoobi et al 8,9 and Rahmani et al 10 also used dynamic equipment for compacting nanocomposites. The effects of B 4 C particles on densification and relative density of Mg have been reported in the literature.…”