Thermal Analysis Study of the Effect of the Cooling Rate on the Microstructure and Solidification Parameters of 319 Aluminum Alloy

Abstract

In the metal casting industry, an improvement of component quality depends mainly on better control over the production parameters. Thus, a thermal analysis cooling curve of the alloy is used for process control in the aluminum casting industry. In this research, the effect of seven different cooling rates on the microstructure and solidification parameters of the 319 aluminum alloy have been investigated by means of thermal analysis. In each case, the cooling curve and its first derivative curve have been plotted by using very accurate thermal analysis equipment. The effect of different cooling rates on solidification parameters such as nucleation temperature (T N,a ), nucleation undercooling (DT N,a ), recalescence temperature (T R,a ), solidification range (DT s ) and total solidification time (t f ) has been studied in the liquidus region. Microstructural evaluation has been carried out and DAS was measured in all solidification conditions.

Assessment of the effect of grain refinement on the solidification characteristics of 319 aluminum alloy using thermal analysis

“…Thermal analysis of alloys can provide information about the composition of the alloy [8], the latent heat of solidification [11,12], the evolution of the fraction solid [8,13], the types of phases that solidify [8,14], and even dendrite coherency [15]. There are also many other uses for thermal analysis, such as, determining dendrite arm spacing [9], degree of modification [16,17] and grain refining [3,5,18] in aluminum alloys, the liquidus and solidus temperatures [8,9], characteristic temperatures related to the eutectic regions and intermetallic phase formation [19,20].…”

“…Different parameters may be obtained from the cooling curve, and these can be related to the grain size [8]. A study of the first derivative cooling curve provides information about the cooling rate of the sample, as well as the beginning and end points of reactions which cannot easily be observed on the cooling curve itself [8][9][10]. In metal casting industry an improvement of component quality mainly depends on better control over the production parameters.…”

Effect of Grain Refinement on the Dendrite Coherency Point during Solidification of the A319 Aluminum Alloy

“…[2,4,5,[10][11][12][13][14][15][16][17][18][19][20][21][22] In the current work, a 319 aluminum alloy was used. The effect of titanium and boron grain refining on the point at which coherency occurs is controversial.…”

Combined effect of bismuth content and cooling rate on microstructure and mechanical properties of Al–8·5Si–0·4Mg–0·3Fe alloy

“…It is necessary in the design of cast components to consider the effect of cooling rate at the different sections and their impact on mechanical properties. 4 In addition, it is not possible to achieve rapid solidification required to obtain a homogenous finer structure. Instead, grain refinement and modification of the morphologies of specific phases by the addition of certain elements such as Ti/B (grain refiner) or Sr (Si modifier) to the melt is commonly used for controlling the microstructures of Al-Si cast alloys.…”