Processing, microstructure, and properties of ternary high-strength Cu–Cr–Ag in situ composites

Abstract A eutectic reaction is a basic liquid-solid transformation, which can be used in the fabrication of high-strength in situ composites. In this study an attempt was made to ensure directional solidification of Fe-C-V alloy with hypereutectic microstructure. In this alloy, the crystallisation of regular fibrous eutectic and primary carbides with the shape of non-faceted dendrites takes place. According to the data given in technical literature, this type of eutectic is suitable for the fabrication of in-situ composites, owing to the fact that a flat solidification front is formed accompanied by the presence of two phases, where one of the phases can crystallise in the form of elongated fibres. In the present study an attempt was also made to produce directionally solidifying vanadium eutectic using an apparatus with a very high temperature gradient amounting to 380 W/cm at a rate of 3 mm/h. Alloy microstructure was examined in both the initial state and after directional solidification. It was demonstrated that the resulting microstructure is of a non-homogeneous character, and the process of directional solidification leads to an oriented arrangement of both the eutectic fibres and primary carbides.

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Microstructure and Properties of Ti-TiN In-Situ Composites Prepared by Reactive Ball Milling of Ti in Ammonia Followed by Hot Pressing

Materials Science Forum ◽

10.4028/www.scientific.net/msf.343-346.399 ◽

2000 ◽

Vol 343-346 ◽

pp. 399-404 ◽

Cited By ~ 1

Author(s):

David Wexler ◽

Andrzej Calka ◽

Ahmed Y. Mosbah

Keyword(s):

Ball Milling ◽

Hot Pressing ◽

In Situ Composites ◽

Microstructure And Properties

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Microstructure and Properties of Al-Zn-Mg-Cu-Mn In Situ High Strength Alloy

Materials Science Forum - PRICM 6 ◽

10.4028/0-87849-462-6.957 ◽

2007 ◽

pp. 957-960

Author(s):

Yuan Hua Cai ◽

Hua Cui ◽

Yong Bing Li ◽

Jing Feng Hang ◽

Ji Shan Zhang

Keyword(s):

High Strength ◽

Microstructure And Properties ◽

Strength Alloy

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A Study on Mechanical Properties and Strengthening Mechanisms of AA5052/ZrB2 In Situ Composites

Journal of Engineering Materials and Technology ◽

10.1115/1.4034692 ◽

2016 ◽

Vol 139 (1) ◽

Cited By ~ 13

Author(s):

Narendra Kumar ◽

Gaurav Gautam ◽

Rakesh Kumar Gautam ◽

Anita Mohan ◽

Sunil Mohan

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

High Strength ◽

Strengthening Mechanism ◽

Strengthening Mechanisms ◽

In Situ Composites ◽

Solid Solution Strengthening ◽

Theoretical Yield ◽

The Matrix

In the present study, in situ reaction technique has been employed to prepare AA5052 matrix composites reinforced with different vol. % of ZrB2 particles (i.e., 0, 4.5, and 9 vol. %). Composites have been characterized by X-ray diffraction (XRD) to confirm the in situ formation of ZrB2 particles in the matrix. Optical Microscopy (OM) studies reveal the refinement of aluminum-rich phase due to the presence of ZrB2 particles. Scanning electron microscopy (SEM) studies reveal size and distribution of ZrB2 particles while transmission electron microscopy (TEM) reveals the presence of dislocations in the matrix around ZrB2 particles. Hardness and tensile testing of composites have been carried out at room temperature to evaluate the mechanical properties. The results reveal the improvement in hardness and strength with increased amount of ZrB2 particles. Strength of AA5052/ZrB2 in situ composites has been analyzed by various strengthening mechanism models. The analysis revealed that Orowan and Solid solution strengthening mechanisms are the predominant mechanism for high strength composites. Theoretical yield strength is about 6–10% higher than the experimental values due to clustering tendency of ZrB2 particles.

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