The effect of sintering temperature, sintering time and reinforcement particle size on properties of Al-Al2O3 composites
Marek Konieczny
Quarterly No. 1, 2012 pages 39-43
DOI:
keywords: metal-matrix composite, aluminium, Al2O3 particles, powder metallurgy
abstract The main aim of this paper was to investigate the effect of sintering temperature, sintering time and reinforcement particle size on the properties of Al-Al2O3 composites. Three sintering temperatures were applied: 500, 550 and 600°C for 30, 60 and 90 minutes. Experiments were performed using specimens containing 0, 5 and 10% of alumina. The average particle sizes of alumina were 2, 10 and 20 [xml:1:97de3e3486]μ[/xml:1:97de3e3486]m. The investigated properties included relative density, hardness and compressive strength. Microstructural observations showed that Al-Al2O3 composites could be successfully formed for all of the studied combinations of sintering temperature, sintering time, alumina particle sizes and amount of reinforcement. The relative density of all the composites increased when the particle size of alumina was reduced. The highest relative density was obtained at 600°C. Higher hardness and compressive strength were observed in samples containing finer Al2O3 particles. The variations in hardness and compressive strength of Al-Al2O3 composites were dependent on the sintering temperature and time. Increasing sintering time at 500 and 550°C led to a gradual increase in hardness and compressive strength. Similar results were obtained as well after sintering at 600°C when the sintering time was increased up to 60 minutes. A prolonged sintering time up to 90 min had a contrary effect on the hardness and compressive strength of the composites.