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Abstract The response of printed hybrid electronic (PHE) assemblies to mechanical shock was previously assessed experimentally but, as with much experimental work, the relevance of these results was limited by the specific intended application. The primary failure mode observed was physical separation of embedded components caused by fractures within sub-surface sintered silver traces and interconnections. This current study focuses on physics-based modeling of these failures, to facilitate extrapolation to other use conditions for broader integration of PHE assemblies within the electronics community, especially for applications experiencing repeated high-g mechanical shock. Modeling efforts integrated all elements of the tested PHE circuit, consisting of molded polysulfone substrates, printed nano-particle ink silver traces, embedded passive components, and printed tin-bismuth soldered interconnects. Circuits were manufactured using a novel ‘mill-and-fill’ hybrid method on a beam measuring 3.2 mm thick, 12.7 mm wide, and 63.5 mm long. The beam was secured by clamped-clamped fixturing along both short edges and subjected to drop testing with no secondary impact. Embedded components were located at regions of maximum bending flexure within the substrate. Simulated base excitation shock levels were based on experimental drop tower testing and ranged from 25,000 g to 100,000 g with pulse durations less than .1 ms. A two-step hierarchical multiscale finite element modeling approach was used, with fully populated models relying on 3D solid elements with explicit dynamic solving and nonlinear effects to account for high peak strain magnitudes (∼18%) and strain rates (∼1,000 /s) in the sintered silver. Validation of a bare substrate model was accomplished prior to maturation of the fully populated model by means of comparing measured and modeled strain response of the substrate in the time domain and frequency domain up to 10 kHz. Given the observed failure sites within the sintered silver traces from experimental work, the maximum stresses and strains at these sites were generated from modeling as a function of base acceleration magnitude and component location on the beam. These values were then compared against experimental cycles to failure data for several different substrate and component geometries with cycles to failure including cumulative damage effects. These geometries included two different strain locations on the beam (edge and center) and two different orientations of the silver trace (longitudinal or transverse) relative to the beam axis. The end result was a geometry- and application-agnostic low-cycle (below 103 cycles) fatigue curve for printed silver traces suitable for applications with repeated loads or as an element of subsequent cumulative damage models. Additional work is ongoing to incorporate the added effects of elevated temperature (up to 125 °C) on the mechanical response of the substrates and silver traces during a mechanical shock.