High-Throughput Calculation (HTC)

High-Throughput Calculation (HTC) view documentations

The High-Throughput-Calculation (HTC) function has been implemented in Pandat software for the PanPhaseDiagram, PanPrecipitation, and PanSolidification modules. It allows a user to perform calculations for thousands of compositions in the user-defined compositional space by a simple setting. Alloy compositions that satisfy user-defined criteria can then be identified through data mining of the thousands of simulated results. The HTC results can be listed in a table or presented as a color map. This function allows users to develop alloys with certain properties through design. Two examples are given below. For databases used by High-Throughput-Calculation, please refer to Databases for more information.

Example 1: HTC for aluminum alloy AA7050 to predict the composition effect

For AA7050, Al constitutes ~90 wt% of the alloy. The major alloying components, Cu, Mg, Zn, and Zr, constitute ~10 wt%, while minor alloying elements, Cr, Fe, Mn, Si, and Ti, only constitute less than 0.5 wt%. HTC is performed in the composition range of Al-(2~2.6)Cu-(1.9~2.6)Mg-(5.7~6.7)Zn-(0.08~0.15)Zr to study the effect of major alloying elements. HTC was carried out for a total of 672 compositions. The following figures show the distribution of liquidus temperature and solidus temperature due to the variation of the major alloying elements.

Next, the effect of minor elements on the liquidus and solidus temperatures of AA7050 is investigated. To do so, the compositions of the major alloying elements are fixed in the middle of their spec ranges.  The HTC is then carried out for this alloy with additions of minor alloying elements in their spec ranges: Al-2.3Cu-2.25Mg-6.2Zn-0.115Zr-(0~0.04)Cr-(0~0.15)Fe-(0~0.1)Mn-(0~0.12)Si-(0~0.06)Ti (wt%). In this case, calculations are performed for a total of 1080 combinatorial compositions. The statistic results that illustrate the effects of these minor elements on the liquidus and solidus temperatures are shown the below figures. As shown in these figures, even small variation of minor elements can affect the solidus temperature significantly.

For details of this study, please refer to the following paper:

R. Schmid-Fetzer and F. Zhang, “The light alloy Calphad databases PanAl and PanMg”, CALPHAD, 61 (2018), p246-263.

Example 2: HTC for the prediction of hot cracking susceptibility

Alloys are susceptible to cracking during solidification. Such cracking is called hot tearing in casting and solidification cracking in welding. Recently, Kou [1, 2] proposed to use an index to evaluate the cracking susceptibility given an alloy composition. Without HTC, cracking susceptibility needs to be evaluated alloy by alloy based on Kou’s theory. In this example, HTC is performed in the Al-Cu-Mg system using PanSolidification module to develop the hot cracking susceptibility map for this ternary system. In the below figure, Figure (a) is the hot cracking susceptibility map obtained by using Scheil model, Figure (b) and (c) are those obtained by using the modified Scheil model for the cooling rate of 100 oC/s and 20 oC/s, respectively, and Figure (d) is the one from experimental observation. Simulations based on modified Scheil model, which considers back diffusion in the solid, give more accurate predictions (Figures b and c).

For details of this study, please refer to the following papers:

[1] S. Kou, A criterion for cracking during solidification, Acta Materialia, 88 (2015), 366-374.

[2] J.W. Liu, S. Kou, Susceptibility of ternary aluminum alloys to cracking during solidification, Acta Materialia, 125 (2017), 513-523.