Characterization of aluminium – copper (Al – Cu) alloy metal matrix composites reinforced by in situ zirconium diboride (ZrB2) / Nurul Hidayah Mustafa

• Main Author: Mustafa, Nurul Hidayah
• Format: Thesis
• Language: English
• Published: 2021
• Subjects: Metals; Aluminum
• Online Access: https://ir.uitm.edu.my/id/eprint/60537/1/60537.pdf; https://ir.uitm.edu.my/id/eprint/60537/

Aluminium – Copper – Zirconium Diboride (Al – Cu – ZrB2) composite have been plug through in situ reaction which promote mechanical abilities on top of dispersion strengthening together with grain refinement accessed by continuation of particular particulates inside the melt for the time being of solidification. Aluminium – Copper (Al – Cu) reinforced which was in situ by various proportion of Zirconium Diboride (ZrB2) which were 0, 3 and 6 wt. % synthesized applying in situ fabrication at 800 °C of molten Al – Cu alloys by inorganic salts Potassium Hexafluorozirconate (K2ZrF6) mixed with Potassium Tetraflouroborate (KBF4). The amalgam itemized using Potential-Dynamic Polarization (PDP) test on suitably segment which were metallographically qualified surface to criticize the corrosion rate itself. Several investigation using XRD, FESEM and mechanical also tested on appropriately sectioned and metallographically prepared surface in order to examine phase distribution, hardness together with tensile properties. From result, raised ZrB2 amount has increase rate of tensile 74% which is 443 MPa and hardness increased 17.6 % with the addition of 6 wt. % ZrB2 reinforcement particles to 147 Hv. XRD patterns exposed development of ZrB2 particulates without existence of unspecified other compounds. Most of ZrB2 granular were located near grain boundaries of Al dendrites. Microstructural investigation on alloy containing 6 wt. % of reinforcement discovered the homogeneous and persistent allocation of second phase particles, clean interface together with favourable bonding due to in situ reaction. It is promoting that ZrB2 molecules are altogether in micro size amidst hexagonal either tetragonal shape, yet minor molecules in micron size were also noticed. For that intention, composite synthesized using in situ techniques indicated homogeneous disposal of reinforcing influenced to be superlative associated within pure interface all over metallic matrix. Outcome of dissimilar ZrB2 percentages all over surface morphology, surface roughness, grain size of Al – Cu alloy were also inspected. Results displayed grain size drop off upon an increase of ZrB2 content in the Al – Cu alloy. Furthermore, the surface roughness was seen to decrease to 1.44 Rα alongside greater ZrB2 concentration of the deposited alloy. In corrosion test conducted, the addition of 6 wt. % ZrB2 gave the good corrosion resistance which is 0.36 × 10-3 mmy-1 compare to unreinforced alloy which mean reinforced alloy has good properties in corrosion characterisation. The result obtained show that in situ Al – Cu alloy composites containing different weight of ZrB2 phase were synthesized successfully using salt – metal reaction method.