Dynamic consolidation of nanostructured Al–7.5%Mg alloy powders

Mechanical properties of bulk aluminium consolidated from mechanically milled particles by back pressure equal channel angular pressing

“…Therefore, it is possible to carry out consolidation at much lower temperatures. It should also be noted that the hardness values of Al consolidated from the milled particles are significantly higher than those of UFG Al after ECAP of ingot [25] or those of Al consolidated from unmilled particles by BP-ECAP [15,16], suggesting that MM is more effective in storing a large amount of strain energy into particles which is mostly kept during the subsequent ECAP consolidation. Further work is now undertaken to determine the optimal parameters for consolidation by BP-ECAP in order to obtain full density.…”

“…A number of consolidation processes have been applied to fabricate bulk nanostructured materials from mechanically milled powders including cold pressing plus hot extrusion [12], cold isostatic pressing plus hot extrusion [13], hot pressing [14], hot isostatic pressing [13], dynamic consolidation [15] and more recently spark plasma sintering (SPS) [16]. These consolidation methods generally involve many steps at relatively high temperatures with long processing times, e.g.…”

Comparison of Two Powder Processing Techniques on the Properties of Cu-NbC Composites

“…It was reported that the yield strength of the composite powder increased with increasing volume fraction of reinforcements [9,36]. The increase of yield strength led to a restriction in the Al [27] Al-Mg [24] Al-Al 3 Mg 2 [38] Fe-TiC [5] AlFe-TiC [25] Cu-Ta [18] BM+SPS BM+CP+S BM+ExC BM+HHP BM+HExt Figure 4: Density of different composites and alloys fabricated by different techniques and consolidation methods. HPT: high pressure torsion, BM+SPS: ball milling followed by spark plasma sintering, BM+CP+S: ball milling followed by cold compaction and sintering, HP: hot pressing, TE: torsion extrusion, BM+ExC: ball milling followed by explosive consolidation, BM+HHP: ball milling followed by high pressure hot pressing, and BM+HExt: ball milling followed by hot extrusion.…”

“…However, powders held at elevated sintering temperatures for long duration lead to grain growth and subsequent loss of mechanical properties [21]. Spark plasma sintering (SPS) and shock compaction with very high heating/cooling rates [14,[22][23][24] or extremely high pressure hot pressing (7.7 GPa) [25] have been applied to achieve full density composites without significant grain growth. These consolidation methods are expensive and difficult to apply.…”

In situ synchrotron X-ray diffraction experiments on Al–15%BN mechanically alloyed powder: Observation of AlN nanoparticles precipitation and enhanced thermal stability of nanostructured Al matrix

“…and, (ii) powder metallurgy (PM) where, nanostructure (10-100 nm) and mechanical alloying are achieved after milling of the powders [4][5][6][7][8][9]. The subsequent consolidation process can be done using different methods: hot isostatic pressing, hot pressing, hot extrusion, cold pressing and sintering and mechanically activated spark plasma sintering (SPS) [10][11][12][13][14][15][16].…”