Abstract: In a method of fabricating an aluminum surface for applying mirror-smooth fabrication to the surface of aluminum or aluminum alloy by combining an electrolytic anode dissolving effect to the surface and a polishing effect of removing the protruded portions of passivated films formed on the surface to be fabricated by lapping with abrasive grains, the voltage between the aluminum material and the tool electrode is set within 2.1.+-.0.3 V, an electrolyte at less than 10% concentration is used as a passivation type electrolyte, the urging pressure of the tool electrode to the surface is set to less than 2.0 kgf/cm.sup.2 and free abrasive grains with the average grain size of less than 1.0 .mu.m are used as the abrasive grains. The temperature of the electrolyte is preferably set to lower than 15.degree. C. The polishing material may comprise non-woven abrasive cloth made of ultrafine fibers.

Abstract: A method of heating a long metal product to a desired temperature by an induction heating coil while continuously moving the long metal product longitudinally. The long metal product thus heated attains a uniform temperature throughout its entire length. For this purpose, the space enclosed by the induction heating coil is hypothetically divided into a plurality of sections in the direction in which the long metal product travels. The temperature of the long metal product in each hypothetically divided section is estimated by calculation from the temperature of the long metal product at the inlet of the induction heating coil. Based on the estimated temperatures, the power supplied to the induction heating coil is controlled so that the temperature of the long metal product agrees with the desired temperature at the outlet of the induction heating coil.