We present our results of SPH simulations of cluster mergers. We investigate the temperature evolution explicitly considering the relaxation process between ions and electrons. The electron temperature distributions are significantly different than those of ions in the later stages of mergers. We also investigate evolution of non-thermal emission from relativistic electrons accelerated around shock fronts. Hard X-ray is luminous only while signatures of merging events are clearly seen in the thermal intracluster medium. On the other hand, extreme ultraviolet emission is still luminous after the system has relaxed.