This study investigates the microstructural and mechanical improvement in a TLP-bonded specimen with the application of PBHT. The microstructure analysis of the TLP-bonded shows an athermal solidified zone at the centre due to inadequate solidification time, while the DAZ contained blocky and needle-shaped Nb-Mo-Cr borides. PBHT results in a more uniform microstructure enhances the amount of γ′ and γ″ precipitates and reduces the boride fraction in the DAZ and second-phase precipitates ISZ. DAZ exhibited the highest hardness due to boride precipitates, while ISZ displayed lower hardness from insufficient alloying elements. PBHT improved hardness across zones by promoting γ′ and γ″ precipitates. Notably, tensile strength in the TLP-bonded specimen significantly improved by 80% with PBHT. These findings underscore the potential for optimizing TLP-bonding processes to enhance mechanical properties.