Thermo-Mechanical Powder Cladding
A cladding process under controlled mechanical post-processing of the solidifying layer, serving for grain refinement and residual stress minimization.
When welding steel, you can mechanically work the weld immediately after laying it, as long as it is still hot and malleable. By controlled pressing or hammering on the not yet solidified weld, you achieve grain refinement in the structure. This makes the weld tougher and reduces internal stresses that could otherwise develop during cooling. If you press too hard, you risk cracks or a damaged surface; with too little pressure, the structure remains coarse and the weld becomes more brittle. So you have to develop a feel for when the weld has the right consistency – it should be soft, but no longer liquid.