Abstract
In situ synthesis of aluminum matrix composites (AMCs) has become a popular method due to several advantages over conventional stir casting method. In the present study, AA7075/ZrB2 AMCs reinforced with various content of ZrB2 particulates (0, 3, 6, 9 and 12 wt.%) were synthesized by the in situ reaction of molten aluminum with inorganic salts K2ZrF6 and KBF4. The composites were characterized using XRD, OM, SEM, EBSD and TEM. The XRD patterns revealed the formation of ZrB2 particulates without the presence of any other compounds. The formation of ZrB2 particulates refined the grains of aluminum matrix extensively. Most of the ZrB2 particulates were located near the grain boundaries. The ZrB2 particulates exhibited various morphologies including spherical, cylindrical and hexagonal shapes. The size of the ZrB2 particulates was in the order of nano, sub micron and micron level. A good interfacial bonding was observed between the aluminum matrix and the ZrB2 particulates. The in situ formed ZrB2 particulates enhanced the mechanical properties such as microhardness and the ultimate tensile strength. Various strengthening mechanisms were identified.
Original language | English |
---|---|
Pages (from-to) | 187-196 |
Number of pages | 10 |
Journal | Engineering Science and Technology, an International Journal |
Volume | 20 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1 Feb 2017 |
Keywords
- Grain boundaries
- Mechanical properties
- Metal matrix composites
- Microstructure
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Civil and Structural Engineering
- Biomaterials
- Mechanical Engineering
- Hardware and Architecture
- Fluid Flow and Transfer Processes
- Computer Networks and Communications
- Metals and Alloys