Work of formation of grain boundaries upon metal plastic deformation

The mechanical treatment of a number of powder metals (Al, Ni, Fe, Cu, Ag, and W) was investigated. It was shown that the work of formation of-rain boundaries A(S) is of the order of several hundreds J/m(2). Using iron powder as an example, it was established that A(S) values are constant at energy doses up to 5-10 kJ/g (the surface area of grain boundaries does not exceed 20 m(2)/g) and independent on the energy intensity of a device (from 10(-1) to 10 W/g). As a rule, the addition of other powder metals (no more than 40 at. %) to iron powder leads to an increase in the As value.