Generally, the Al-PTFE is thought to be inert under quasi-static or static loads. However, here we reported an initiation phenomenon of Al-PTFE under quasi-static compression. SEM and finite element simulation results suggest that the initiation was directly related to crack propagation and sliding interfaces in severely sheared regions. Calculation results show that the deformation induced temperature rise is only 28.6 degrees C and no melted Al or PTFE were observed in recovered samples in the critical initiation state. Therefore, the initiation is more like a mechanochemical process rather than a thermochemical one. (C) 2015 Elsevier B.V. All rights reserved.