A process for forming oxide based dense ceramic composite coatings on reactive
metal and allow bodies involves suspension of at least two reactive metal or alloy
bodies in a non-metallic, non-conducting, non-reactive chamber in such a way that
it causes either partial or full immersion of the bodies in a continuously circulating
electrolyte. Thyristor controlled, modified shaped wave multiphase alternating
current power supply is applied across the bodies where in each body is connected
to an electrode. Electric current supplied to the bodies is slowly increased to
a particular value till the required current density is achieved and the maintained
at the same level throughout the process. Visible arcing at the surface of the
immersed regions of the bodies is identified when the applied electric potential
crosses 60V. Electric potential is further increased gradually to compensate the
increasing resistance of the coating. Electrolyte composition is regulated through
the changes in pH and conductivity of the electrolytic solution, Thickness of the
coating formed on the bodies is monitored by the time for which the electrical
power at constant current density is supplied to the bodies. The contains obtained
are found to exhibit higher density and excellent wear.
