Synergistic Strengthening Effect of Reinforcing Spark Plasma Sintered Al-Zn-TiC Nanocomposites with TiC Nanoparticles

Hany S Abdo,Ahmed Fouly,Asiful H Seikh,Sameh A Ragab

doi:10.3390/cryst11080842

Abstract

In this investigation, Al-10Zn-TiC nanocomposite powders were prepared by varying the reinforcement content in wt.% via mechanical alloying in order to fabricate bulk samples via spark plasma sintering technique. The grain size exhibited in bulk samples was 17 ± 08 μm in 10 wt% TiC reinforced nanocomposites. The introduced TiC nanoparticles were improved the load carrying ability of the final product. The advanced microscopic studies such as X-ray diffraction analysis, SEM, HR-TEM along with the ring pattern were analysed to ensure the phases and their distribution of reinforced nanoparticles in the Al matrix. The XRD results revealed the formation of TiC present in the matrix, and SEM analysis conveys the uniform distribution and absence of clustering among the reinforcement particles; TEM results depicted the clear interface between the matrix and TiC nanoparticles. The mechanical properties such as hardness and compression studies were carried out in the bulk specimens. The obtained results confirmed the nanocomposites exhibit higher strength which was not only due to decrease in grain size but also due to the occurrence of different strengthening mechanisms such as grain boundary, Orowan and thermal expansion coefficient mismatch strengthening commensurate with the nanoscale TiC addition.

Highlights

Lightweight materials with high strength are vigorously required in aviation sector.The weight reduction of engine parts improves in fuel efficiency in service conditions, which can be gratified by Al matrix composites (AMC) without compromising the mechanical properties [1]
The carbide particles reinforcement in the AMCs leads to improvement in the strength of the final product
In High Energy Ball Milling (HEBM), vial and plate speed were kept as 280 rpm and 105 rpm for the duration of 20 h; to get rid of temperature rise inside the bowl, working time and down time were set as 45 min and 15 min continuously

Summary

Introduction

Lightweight materials with high strength are vigorously required in aviation sector. The weight reduction of engine parts improves in fuel efficiency in service conditions, which can be gratified by Al matrix composites (AMC) without compromising the mechanical properties [1]. The carbide particles reinforcement in the AMCs leads to improvement in the strength of the final product. The powder metallurgy is a promising technique to produce AMCs by avoiding cluster formation among introduced second phase ceramics, in which mechanical alloying produces nanocomposite (NC) particles with uniform distribution of reinforcement particles in Metal Matrix Composites (MMCs). The high energy collision of the un-milled AMC particles makes them to bond temporarily and makes them to get fractured. The materials used in this work are commercially pure Al (99.5% purity) as matrix material, Zn (99.5% purity) as alloying element to form solid solution and TiC ceramic particles (>99% purity) as reinforcement, procured from M/s (Sigma-Aldrich, Burlington, VT, USA). Ball Milling Processes of Al/TiC Powders [Al–10Zn]–TiC nanocomposites were synthesised using High Energy Ball Milling (HEBM). Examining the Morphologies of Matrix Grains and TiC Nanoparticles In addition to the observation of TiC nanoparticles dispersion, morphologies of matrix grains and TiC nanoparticles along with the strengthening factor such as dislocations

Examining the Morphologies of Matrix Grains and TiC Nanoparticles

Vickers Micro-Hardness Examination

Findings

Conclusions