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This paper was Featured, and appeared on the cover of the Journal The article of record as published may be found at https://doi.org/10.1063/5.0011264 In this work, microstructure dependent impact-induced failure of hydroxyl-terminated polybutadiene (HTPB)ﾖcyclo-tetra-methylene-tetra- nitramine (HMX) energetic material samples is studied using the cohesive finite element method (CFEM). The CFEM model incorporates experimentally measured viscoplastic constitutive behavior, experimentally measured interface level separation properties, and phenomeno- logical temperature increase due to mechanical impact based on viscoplastic and frictional energy dissipation. Nanoscale dynamic impact experiments were used to obtain parameters for a strain-rate dependent power law viscoplastic constitutive model in the case of bulk HTPB and HMX as well as the HTPBﾖHMX interfaces. An in situ mechanical Raman spectroscopy (MRS) setup was used to obtain bilinear cohe- sive zone model parameters to simulate interface separation. During analyses, the impact-induced viscoplastic energy dissipation and the frictional contact dissipation at the failed HTPBﾖHMX interfaces is found to have a significant contribution toward local temperature rise. Microstructures having circular HMX particles show a higher local temperature rise as compared to those with diamond or irregularly shaped HMX particles with sharp edges indicating that the specific particle surface area has a higher role in temperature rise than particle shape and sharp edges. Regions within the analyzed microstructures near the HTPBﾖHMX interfaces with a high-volume fraction of HMX particles were found to have the maximum temperature increase. Financial support from the Air Force Office of Scientific Research (AFOSR), Dynamic Materials and Interactions Program (Grant No. FA9550-19-1-0318 Financial support from the Air Force Office of Scientific Research (AFOSR), Dynamic Materials and Interactions Program (Grant No. FA9550-19-1-0318