Nonequilibrium synthesis of Ni-Al-Si alloys by laser processing

In the present work, three kinds of alloys with nominal compositions (at. %) of Ni-25Al, Ni-15Al-10Si and Ni-5Al-20Si have been fabricated successfully by a 10 kW continuous wave CO₂ laser under optimum processing conditions. X-ray diffraction (XRD) results showed that the phases of all alloys consisted mainly of Ni-Al type intermetallic compounds. The microstructures of three alloys were characterized using scanning electron microscopy (SEM). The hardness was measured on a HX-1000TM Vickers microhardness tester. The average hardness of Ni-15Al-10Si alloy was the highest value of 914 HV compared with Ni-25Al and Ni-5Al-20Si alloys.