Improvement of metallurgical properties of A356 aluminium alloy by AlCrFeSrTiBSi master alloy

A new AlCrFeSrTiBSi master alloy was manufactured by in situ synthesis in Al melt, and compared with AlBSr master alloy. Microstructures of A356 alloy modified with AlCrFeSrTiBSi master alloy were investigated, and the structural details of the new cast A356 alloy were evaluated by X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), microhardness and differential thermal analysis (DTA). AlBSr master alloy typically formed alpha-Al and granular SrB6 phases in A35(6), and the samples inoculated with AlCrFeSrTiBSi master alloy consisted of additionally AlCrFeSi phase with irregular blocks. The addition of 0.1 wt%AlCrFeSrTiBSi alloy to the A356 alloy significantly refined and modified the grain structure together. The structure of eutectic Si converted from acicular form to fibrous. The size of alpha-Al dendrites declined from similar to 1000 mu m to similar to 100 mu m. The strength values of the A356 alloy were developed by similar to 70% with the addition of 0.1 wt%AlCrFeSrTiBSi master alloy.

Automated summary

A new AlCrFeSrTiBSi master alloy was synthesized in situ in an Al melt and compared with the AlBSr master alloy. The microstructures and structural details of A356 alloy modified with AlCrFeSrTiBSi master alloy were investigated using various techniques. The addition of 0.1 wt% AlCrFeSrTiBSi alloy significantly refined and modified the grain structure of the A356 alloy, leading to an increase in strength by approximately 70%.