Fabrication of intermetallic compound matrix composite by spontaneous infiltration and subsequent in situ reaction processes

A planetary ball milling (PBM) technique was employed to fabricate mechanically alloyed (MA processed) Al-Nb2O5 composite powder. Nano or sub-micron sized Nb2O5 particles were homogeneously embedded in the Al particles after milling for various periods. None of cracks, by-products and pores were observed in the areas between embedded Nb2O5 particulates and Al matrix powder after milling. The sequence of the in-situ reaction was confirmed by DSC, XRD measurements, optical microscopy and EPMA. The specific temperature of the in-situ reaction was between 650 and 700°C. Al-based metal matrix composites (MMC) reinforced with the sub-sieve sized θ-Al2O3 particulates and Al3Nb intermetallic compound were successfully fabricated by the in-situ reaction process. The substituted Nb by the in-situ reaction was fully reacted with Al to form the Al3Nb intermetallic compound during sintering. A number of sub-sieve sized θ-Al2O3 particulates and Al3Nb intermetallic compound formed by the in-situ reaction between Al and Nb2O5 were homogeneously distributed in the Al matrix during sintering. Nano sized θ-Al2O3 particulates are preferentially distributed near the Al3Nb intermetallic compound and no by-products are formed in the interfaces with the Al matrix.

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Development of magnesium-based hybrid metal matrix composite through in situ micro, nano reinforcements

Journal of Composite Materials ◽

10.1177/0021998320946432 ◽

2020 ◽

Vol 55 (1) ◽

pp. 109-123 ◽

Cited By ~ 2

Author(s):

Harprabhjot Singh ◽

Deepak Kumar ◽

Harpreet Singh

Keyword(s):

Metal Matrix Composite ◽

Matrix Composite ◽

Metal Matrix ◽

Nano Particles ◽

Ceric Ammonium Nitrate ◽

Energy Dispersion Spectroscopy ◽

In Situ Reaction ◽

Optical Profilometer ◽

Hybrid Metal Matrix Composite

Present work aims at developing Magnesium based metal matrix composite (MMC) through in-situ reaction. In-situ generation of micro and nano particles in the Mg-melt is supposed to have a better bonding with the matrix. Ceric ammonium nitrate (CAN) is added to initial Magnesium melt (with an aim to generate CeO2 and MgO through in-situ reaction) at temperatures of 670 °C and 870 °C. The developed MMCs are solution treated to get rid of intermetallic. The nature of particles is explored with X-ray diffraction (XRD) and Energy dispersion spectroscopy (EDS). The morphology and sizes of particles are keenly jotted using scanning electron microscope (SEM). Mechanical responses of developed MMCs are recorded through Hardness, Compression and scratch tests. The compression fractured surfaces are analyzed with SEM and scratched samples are analyzed on 3 D optical profilometer to explore deformation behavior. The observations indicate the in-situ formation of CeO2, MgO and CeMg12 intermetallic phases in different types and sizes. Further, these particles are responsible for improved mechanical properties. The findings are supported by the contribution of different strengthening mechanisms.

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