The invention relates to circuit boards consisting of a flat core plate, 1 to 5 mm thick, of metallic material, graphite or electrically conductive carbon with a coating, 10 to 80 .mu.m thick, of electroplated aluminum eloxal and, optionally, an intermediate layer of copper or silver, 0.1 to 2 .mu.m thick. On the electroplated Al eloxal layer, a conductor run structure generated by an additive or subtractive technique may be present. The highly heat-conducting and mechanically strong circuit boards find application in electronics.