It is shown by the example of welding of heterogeneous metals of pair “steel 20 copper M1” in solid state with use of current pulses that the changes in pressure within the range from 0.35 to 0.5 from the yield point of the less strong metal is more expedient. It is determined that in this case the level of local microdeformations makes from 40 to 50%, which provides a rather tight contact between the weldable surfaces as applied to the studied method of welding, thus allowing in the process of further treatment to insulate them through the current from the surrounding medium, and creates the possibility to get a welding junction without vacuumizing or protective medium, which is confirmed by an experimental check-up.