Abstract A two-dimensional Finite Difference (FD) model of the thermal history of parts manufactured in powder bed fusion Additive Manufacturing (AM) processes is presented. The temperature of the part is calculated in each time-step taking into account the moving laser heat source, the melting phase change and functions of both temperature and porosity are used for the material thermal properties. Also, an algorithm for node birth and distance adaptation over time is utilized, minimizing computational time and memory. A validation of the results of the model is included.