Within the scope of the study, NdFeB-based permanent magnet alloys produced by melt spinning method, which is a kind of rapid solidification method and enables the production of amorphous and/or semi-crystalline alloys in the form of strips, were produced. In addition, the effect of flash annealing heat treatment on magnetic properties at 680 and 710 °C for 10 minutes using very fast heating and cooling rates of 290 K/s was investigated. A new alloy was obtained by adding 30% by weight of waste magnet to the NdFeB based permanent magnet alloy used in our study. In addition to the effect of heat treatment, another aim of our study is to reuse waste magnets and to recover rare earth elements from waste magnets. Along with the increasing heat treatment temperature, a decrease was observed in magnetic coercivity from 16546 Oe to 2349 Oe, maximum energy product from 136 kJ/m3 to 10 kJ/m3, and magnetic remenance from 56 emu/g to 22 emu/g, which reveals permanent magnetism. On the other hand, there was no significant change in saturation magnetization, but a slight increase was observed from 93 emu/g to 90 emu/g.