Static relaxation simulation and a systematic analysis of the local atomic structure have been performed to investigate the microstructure of amorphous Co-B alloys with pair Pak-Doyama-like potentials for all the bonds in systems. Calculations show the existence of large vacancy-like cavities in the amorphous state. The Monte Carlo method and the Ising model have been used to simulate the magnetic properties of fcc Co, amorphous Co and Co-B alloys. The temperature dependence of magnetization, local magnetization distribution and critical boron concentration for the onset of spontaneous magnetic order have been investigated and presented.
