Abstract: The invention relates to a method for producing a sintered silicon carbide article having a sintered density of at least 90% of the theoretical density and a mechanical flexural strength of 50 kg/mm.sup.2 or higher. This is achieved by adding to a finely divided .alpha.-type silicon carbide powder, a tar pitch in such amounts as to provide 4.2-6 parts by weight of carbon after carbonization and a boron compound such as to correspond to a boron content of 0.005-0.15 parts by weight as densification aids, mixing and shaping the resulting mixture, and then sintering the thus-shaped article in an inert atmosphere at a temperature of from 1950 .degree. to 2300.degree. C.

Abstract: An improved process for the production of a low density formed product of an activated alumina having a large macro-pore volume and an excellent abrasion resistance, which comprises mixing the starting solid material selected from an alumina powder being able to be re-hydrated and a mixture of the alumina and other solid material with water, said starting solid material having an average particle size of 1 micron to 35 micron and a quarter deviation of particle distribution of not more than about 1.5, forming the mixture of a solid material and water into various shapes, re-hydrating the formed product by keeping it under wetted atmosphere or in water, and calcining the resulting re-hydrated product.

Abstract: An electrode for aluminum reduction cells wherein an electrode base, at least in that portion which is brought into contact with a molten salt bath, is coated with a composition comprising at least 50% by weight of electronic conductive oxide ceramics, or said portion of the electrode is made of said composition.

Abstract: A rotor conductor of a squirrel-cage induction motor is made of an aluminum-base alloy consisting essentially of 0.3 to 4% by weight of manganese, 0.15 to 0.9% by weight of chromium, 0.05 to 0.6% by weight of titanium, 0.01 to 0.12% by weight of boron, not more than 0.3% by weight of iron and not more than 0.3% by weight of silicon, the balance being aluminum, said squirrel-cage rotor generating a large starting torque.