Abstract:Commercially AA1070 aluminium was processed by micro/mesoscale equal channel angular pressing (ECAP) up to four passes, via route [Formula: see text], to achieve fine grain structure and thereby enhancing the mechanical properties. Subsequently, the samples subjected to ECAP processing underwent an extrusion deformation in micro/mesoscale. The microstructural evolution of the deformed structures was followed using electron backscatter diffraction. The findings confirm that a remarkable refinement in the grain … Show more
“…The broad aspects of microstructure evolution during MMSECAP/MMSE were displayed in our previous work of the present authors [26,27]. For suitability, the main issues of this process are shortly summarised here.…”
Section: Resultsmentioning
confidence: 89%
“…Moreover, the microstructure consists mainly of a large fraction of LAGBs as already shown in Figure 2(b), qualitatively. Figure 2 EBSD orientation maps: (a) undeformed; (b) one ECAP pass; (c) two ECAP passes; (d) three ECAP passes; (e) four ECAP passes; and (f) High-magnification EBSD map for the 4th ECAP pass on an area of 20 µm × 20 µm [26,27]. …”
Section: Resultsmentioning
confidence: 99%
“…Thus, in our previous works [26,27], a miniaturised version of micro/meso-scale ECAP (MMSECAP), as well as micro/meso-scale extrusion (MMSE) dies as new techniques for fabricating miniaturised parts, were designed and implemented for improving the feasibility of micro-components manufacturing. Additionally, the microstructural evolution of the samples subjected to ECAP as a pre-processing method followed by micro/meso-extrusion processing to improve the grain structure of AA1070 alloy was investigated.…”
The micro-injection upsetting (MIU) experiments of commercially pure aluminium have been conducted on two groups of specimens with different grain structures. One group is of coarse grain (CG, undeformed) and the other group is of fine grain (FG) achieved via the 4th pass equal channel angular pressing in micro-meso/scale. The two groups were further processed by micro/meso-scale extrusion before conducting MIU for fabricating tiny pins. Micro-upsetting test of the tiny pins showed that the material has a good isotropic flow forming and is free of unde-sirable defects comparing with the CG counterparts, which can be ascribed to the decreasing of grain boundary strengthening effect in the case of FG structure.
“…The broad aspects of microstructure evolution during MMSECAP/MMSE were displayed in our previous work of the present authors [26,27]. For suitability, the main issues of this process are shortly summarised here.…”
Section: Resultsmentioning
confidence: 89%
“…Moreover, the microstructure consists mainly of a large fraction of LAGBs as already shown in Figure 2(b), qualitatively. Figure 2 EBSD orientation maps: (a) undeformed; (b) one ECAP pass; (c) two ECAP passes; (d) three ECAP passes; (e) four ECAP passes; and (f) High-magnification EBSD map for the 4th ECAP pass on an area of 20 µm × 20 µm [26,27]. …”
Section: Resultsmentioning
confidence: 99%
“…Thus, in our previous works [26,27], a miniaturised version of micro/meso-scale ECAP (MMSECAP), as well as micro/meso-scale extrusion (MMSE) dies as new techniques for fabricating miniaturised parts, were designed and implemented for improving the feasibility of micro-components manufacturing. Additionally, the microstructural evolution of the samples subjected to ECAP as a pre-processing method followed by micro/meso-extrusion processing to improve the grain structure of AA1070 alloy was investigated.…”
The micro-injection upsetting (MIU) experiments of commercially pure aluminium have been conducted on two groups of specimens with different grain structures. One group is of coarse grain (CG, undeformed) and the other group is of fine grain (FG) achieved via the 4th pass equal channel angular pressing in micro-meso/scale. The two groups were further processed by micro/meso-scale extrusion before conducting MIU for fabricating tiny pins. Micro-upsetting test of the tiny pins showed that the material has a good isotropic flow forming and is free of unde-sirable defects comparing with the CG counterparts, which can be ascribed to the decreasing of grain boundary strengthening effect in the case of FG structure.
“…The crystallite size was assessed by the classical Williamson-Hall method (FWHM) from the broadening of XRD peaks and using the following formula [37,38]:…”
Section: Xrd Analysismentioning
confidence: 99%
“…The crystallite size of pure copper was ~105 nm, whereas the crystallite size for the produced composites was in the range of 5-25 nm. The crystallite size was assessed by the classical Williamson-Hall method (FWHM) from the broadening of XRD peaks and using the following formula [37,38]:…”
Bi-modal particles are used as reinforcements for Cu-matrix. Nano TiC and/or Al2O3 were mechanically mixed with Cu particles for 24 h. The Cu-TiC/Al2O3 composites were successfully produced using spark plasma sintering (SPS). To investigate the effect of TiC and Al2O3 nanoparticles on the microstructure and mechanical properties of Cu-TiC/Al2O3 nanocomposites, they were added, whether individually or combined, to the copper (Cu) matrix at 3, 6, and 9 wt.%. The results showed that titanium carbide was homogeneously distributed in the copper matrix, whereas alumina nanoparticles showed some agglomeration at Cu grain boundaries. The crystallite size exhibited a clear reduction as a reaction to the increase of the reinforcement ratio. Furthermore, increasing the TiC and Al2O3 nanoparticle content in the Cu-TiC/Al2O3 composites reduced the relative density from 95% for Cu-1.5 wt.% TiC and 1.5 wt.% Al2O3 to 89% for Cu-4.5 wt.% TiC and 4.5 wt.% Al2O3. Cu-9 wt.% TiC achieved a maximum compressive strength of 851.99 N/mm2. Hardness values increased with increasing ceramic content.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
