Heterogeneous metal 4D printing presents a promising technological route for fabricating structures with controllable thermally induced deformation. This approach addresses limitations inherent in shape memory alloy components, particularly their restricted number of stable deformation cycles, thereby offering broader application potential. Nonetheless, heterogeneous metal 4D printing remains at a conceptual stage, with limited research on process selection, interfacial bonding characteristics and thermally induced deformation behaviour. This study investigates the 4D printing of heterogeneous metals via laser solid forming of 316L/Invar36 alloys, focusing on the influence of process parameters and deposition configurations on interface flatness, compositional transition across the interface and thermally induced deformation. The results demonstrate that, with all other parameters held constant, decreasing the laser power within the 1000–1800 W range leads to a flatter interface and narrows the compositional transition zone between 316L and Invar36 alloys. At a laser power of 1000 W and scanning speed of 15 mm/s, strip-shaped specimens fabricated through vertical stacking of the two materials exhibit pronounced deformation under thermal actuation. In contrast, side-by-side deposition results in a jagged interface and a broader compositional transition zone, significantly diminishing the thermal actuation deformation of the resulting strip specimens. When 316L and Invar36 are alternately arranged in both vertical and horizontal orientations, the strips exhibit S-shaped deformation under thermal stimulation. Assembled from multiple such strips, a heterogeneous metal spring structure capable of substantial deformation is obtained, displaying a deformation magnitude 2.58 times greater at 270 °C than at 25 °C.