ZnS ceramic has been extensively used in various optical applications, e.g. fullwave band infrared window. The attractiveness of this material is explained by its wider transmission radiation range and higher infrared transmittance. An infrared window has often to be bonded to the protective metal frame due to high risk of involving demanding operational conditions, e.g. a vibration. So, an innovative joining technique must be necessarily uncovered. The objective of this work was designed to use a low temperature glass powder to directly solder/braze ZnS ceramics during the temperature range between 400 and 450 oC. Our hypothesis was that the mechanical strength between ZnS glass and PbO-B2O3-ZnO powder would be significantly enhanced by doping the solder/braze by PbTiO3 particles. The formed interfacial reaction layer consists of PbS and the uniformly dispersed PbTiO3 particles. A heuristic explanation of the bonding mechanism is offered and it is found that the use of sintering remelting can reduce defects within the glass joints. Owning to the second-phase diffusion strengthening of PbTiO3 particles and an interfacial chemical bonding in the joint, the mechanical properties is enhanced.