What is the definition of mechanical waves

A mechanical wave is a wave where there's
some material doing the waving.

Examples:

-- ripples on water
-- waves on a rope
-- waves on a spring
-- waves on a Slinky
-- sound waves in air
-- seismic waves in rock
-- vibrations on a guitar string
-- vibrations on a violin string

A mechanical waves is a wave that is an oscillantion of matter, and therefore transfers energy through a medium.

I'm not sure what your asking buddy.. but i know that you can weld two peices of steel by pure force and pressure.