<p>This study investigates the transient thermomechanical response of a solid circular cylinder containing microscopic voids when exposed to two simultaneous thermal excitations: a gradually increasing ramp-type thermal shock applied at the outer surface, and an internal pulsed heat source whose intensity decays exponentially with radial penetration into the material. The cylinder is assumed rigidly fixed at its outer boundary, while the void field obeys a mixed surface condition that allows partial venting of pore pressure. The theoretical framework uniquely combines three advanced physical concepts: spatio-temporal nonlocality of the Klein–Gordon type, a higher-order three-phase-lag heat conduction model capturing finite thermal wave speeds, and full coupling between temperature, displacement, and void dynamics. The governing equations are solved using a hybrid analytical–numerical method. Laplace transformation reduces the system to ordinary differential equations, whose solutions are expressed in terms of modified Bessel functions. The unknown coefficients are determined by applying the transformed boundary conditions: a ramped temperature rise at the surface, zero radial displacement, and the mixed void condition. Numerical inversion of Laplace transforms yields time-domain results. Key findings show that increasing the ramp rise time significantly reduces peak temperature and stress levels, avoiding unphysical singularities. A higher attenuation coefficient confines heating near the surface, protecting the cylinder interior. An impermeable surface suppresses void expansion near the boundary, altering local stress distributions. Simultaneous activation of both spatial and temporal nonlocality reduces hoop stress by up to thirty-five percent, providing intrinsic damping. This work offers direct engineering guidelines for designing lightweight porous components in aerospace, nuclear, and biomedical applications under severe thermal shocks with mechanical constraints.</p>