An Experimental Study of the Solidification Thermal Parameters Influence upon Microstructure and Mechanical Properties of Al-Si-Cu Alloys

Abstract

Metals solidification involves the transformation of the molten metal back into the solid state. Solidification structures impact heavily on the final product's characteristics. The microstructure effects on metallic alloys properties have been highlighted in various studies and particularly the dendrite arm spacing influence upon the mechanical properties such as tensile strength has been reported. In the present investigation, Al-10wt%Si-2wt%Cu and Al-10wt%Si-5wt%Cu alloys were directionally solidified upward under transient heat flow conditions. The experimental results include solidification thermal parameters such as tip growth rate and cooling rate, optical microscopy, volume fraction of the eutectic mixture, primary dendritic arm spacing and ultimate tensile strength. Experimental growth laws of primary dendrite arm spacing as a function of the solidification thermal parameters are proposed. The Hall-Petch mathematical expressions were used to correlate the ultimate tensile strength as a function of the primary dendritic arm spacing. It was found that the alloy with higher copper content had a more refined structure. More refined structures had higher ultimate tensile strength values.

Effects of Thermal Variables of Solidification on the Microstructure, Hardness, and Microhardness of Cu-Al-Ni-Fe Alloys

“…Directional solidification allows different microstructures to be obtained in the length of the molten ingot, influencing the alloy properties. The effects of the manufacturing processes on the microstructure and properties of engineering materials have been highlighted in various studies [14,15,16,17,18,19,20]. Thermal parameters of solidification, as tip growth rate (V L ) and cooling rate (T R ), were correlated with hardness and microhardness values for both alloys studied.…”

Modified Scheil equation for the Cu-Sn system and comparison of hardness and electrical conductivity of Cu-8.5wt% Sn alloy directionally solidified

“…Thermocouples, a data acquisition system, and a computer allowed monitoring the temperature in eight sites of the cylindrical casting. More details of this technique is found in the literature [2][3][4].…”

Comportamento Mecânico Em Tração E Impacto De Compósitos De Matriz Poliéster Reforçados Com Fibras De Timbó-Açu

“…Devido a trabalhos e estudos já realizados, sabese que o processo de manufatura utilizado definirá as características do produto final, tais como resistência mecânica. (Nascimento et al, 2017;Nascimento et al, 2018;Nascimento et al, 2019;Santos et al, 2017) O nióbio, na tabela periódica, é o elemento de número 41 dos elementos químicos, possui massa especifica de 8,57 (ROBERT, 1983;DE MATTOS et al, 2020).…”