PURPOSE: To produce a flawless sintered article with the variations in quality reduced at a high rate and to drastically reduce the cost mainly in the production of a battery plaque.

CONSTITUTION: A fine nickel powder is applied on the skeleton of a urethane resin foamed body and sintered to produce a battery plaque. In this case, the fine nickel powder at the time of application is treated with an alternating magnetic field and magnetized to form a dense and uniform layer of fine Ni powder around the skeleton and simultaneously to form a stably shaped sheet in which the fine Ni powders are magnetically combined, and the sheet is dried, dewaxed and sintered in a short time by using a high-frequency coil.