Effect of semi-solid forging on microstructure and mechanical properties of in-situ cast Al-Cu-TiB 2 composites

Abstract

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Effect of Fe Intermetallics on Microstructure and Properties of Al-7Si Alloys

“…The detailed test procedure can be found elsewhere. 12,13 The peak indentation depth (h max ) is the maximum displacement of the indenter from its initial position at peak load (P max ). It includes both elastic and plastic deformation.…”

“…where P max is the peak load and A is the projected area of contact between the indenter and the sample. 13,15 Mechanical Property Characterisation…”

X-Ray Tomography Study on Porosity and Particle Size Distribution in In Situ Al-4.5Cu-5TiB2 Semisolid Rolled Composites

“…1 Al-Cu alloy-based metal-matrix composites (MMCs) have found wide applications in the automobile industry owing to their high specific strength, reasonable ductility, and excellent wear resistance, which make them suitable for applications involving sliding wear and highstrength load-bearing parts. 1,2,[4][5][6][7][8][9][10][11][12][13] Over the last decade, TiB 2 -reinforced Al-Cu MMCs have attracted significant interest. 3,[5][6][7]9 TiB 2 has excellent properties as a reinforcement particle, such as high hardness (960 HV), high elastic modulus (530 GPa), and high melting point (2790°C), 13,14 and most importantly does not react with the Al matrix even at very high temperatures.…”

“…1,2,[4][5][6][7][8][9][10][11][12][13] Over the last decade, TiB 2 -reinforced Al-Cu MMCs have attracted significant interest. 3,[5][6][7]9 TiB 2 has excellent properties as a reinforcement particle, such as high hardness (960 HV), high elastic modulus (530 GPa), and high melting point (2790°C), 13,14 and most importantly does not react with the Al matrix even at very high temperatures. 8,15 Furthermore, TiB 2 particles can act as nucleating sites for primary aluminum, resulting in grain refinement of the alloy by pinning grain boundaries when added at low levels, while it also acts as a particulate reinforcement when added at higher proportions, changing metal alloys to metal-matrix composites.…”

“…12 These problems led to the development of in situ Al-Cu-TiB 2 composites processed by a liquid metallurgy route using K 2 TiF 6 and KBF 4 salts. [3][4][5][6][7] However, these salt reactions result in an inhomogeneous distribution of in situ submicron-sized TiB 2 particles, as the particles tend to form clusters which deteriorate the mechanical properties of the composites. 10,[17][18][19] It has also been observed that submicron-sized TiB 2 particles are pushed towards grain boundaries during solidification.…”