A Bruker D8 ADVANCE x-ray diffractometer with a Cu Kα radiation was used to analyze the powders and bulk samples. EBSD was performed using an Oxford Instruments Nordlys Nano detector that is equipped to a Phillips XL-30 SFEG SEM. An Oxford Channel 5 software was adopted to analyze the EBSD data. In addition, a JEOL JEM-2100 (200 kV) and a JEOL JEM-2500SE (200 kV) TEM with SAED and with EDS were used to observe the microstructure and to obtain chemical compositions of the Fe25Co25Ni25Al10Ti15 HEA. TEM specimens were first polished to ~20 μm and then thinned to electron transparency by ion milling.