bonding technique as shown in fig. Other joining techniques such as brazing
roll bonding, or diffusion bonding may also appropriate for rotor construction.
sheets of ferromagnetic and non-ferromagnetic steel are bonded. The bonded
sheets are then cut into rectangular blocks h\which are machined into the
desired rotor. The rotor shaft can also be machined out of the same block as
joining technique known as explosion bonding. Explosion bonding uses explosive
energy to force two or more metal sheets together at high pressures. Conventionally
the high pressure causes several atomic layers on the surface of each sheet to
behave as a fluid. The angle of collision between the two metals forces this
fluid to jet outward. Effectively cleaning the metal surface, these ultra clean
surfaces along with the high pressure forcing the metal plates together provide
the necessary condition for solid phase welding.
tests on a stainless steel/mild steel bond indicate that the tensile and
fatigue strengths of the bond are greater than those of either of the component
materials due to the shock hardening which occurs during the process. The bond
was also subjected to 10 cycles of temperature variation from 20° C - 70°C,
with no significant reduction in tensile strength.