Effect of sintering on microstructure and mechanical properties of nano-TiO2 dispersed Al65Cu20Ti15 amorphous/nanocrystalline matrix composite

Microstructural Evolution and Mechanical Properties of Nanointermetallic Phase Dispersed Al65Cu20Ti15 Amorphous Matrix Composite Synthesized by Mechanical Alloying and Hot Isostatic Pressing

“…The first of these two observations can be attributed to strengthening by the presence of relatively harder nanocrystalline intermetallic particles in case of the composites prepared by HIP and PPS. On the other hand, the second observation can be explained on the [36] and CCS [30] are shown for comparison. basis of the similarities in microstructural constituents, as well as lower defect concentration in the composites prepared by PPS.…”

“…[25,30] Figure 2 shows the XRD patterns of the composite samples prepared by HIP in the temperature range of 573 K to 873 K (300°C to 600°C). These patterns suggest that the process of sintering led to partial crystallization of the as-milled amorphous aggregate into several ultrafine intermetallic phases such as Al 5 CuTi 2 , [31] Al 4 Cu 9 , [32] Al 3 Ti, [33] and Al 2 Cu.…”

“…Furthermore, the results obtained for other methods of consolidation including high pressure sintering (HPS), [35] pulse plasma sintering (PPS), [36] and CCS [30] are also included in Figures 5(a) and (b) for comparison. Table I provides a comprehensive summary of the phase aggregate after sintering of the mechanically alloyed powder with nominal composition of Al 65 Cu 20 Ti 15 through various routes including conventional pressure less sintering.…”

“…Examination of the results of studies on materials prepared by different processing routes, as shown in Figures 5(a) and (b) as well as Table I, lead to the following inferences: (1) it has been possible to achieve greater densification at a lower temperature (673 K (400°C)) by HPS than that by HIP; (2) the density increases and the pore content decreases sharply between 673 K and 773 K (400°C and 500°C) and more gradually at higher temperatures for the samples processed by either PPS or CCS; (3) the maximum density achieved by CCS at temperatures up to 873 K [36] and CCS [30] are included for comparison.…”

“…In the plots of cumulative acoustic emission against stress, the stress corresponding to the initiation of failure is distinguished by the rapid increase of acoustic emission activity marked by arrowheads. On examination of Plots depicting the results obtained for samples prepared by HPS, [35] PPS, [36] and CCS [30] are included for the purpose of comparison.…”