Abstract: Granulated polyethylene is agitated and mixed with a solution of silane with peroxide, activators and anti-oxidants and at a temperature between 80.degree. to 100.degree. C to obtain diffusion of these additives into the polyethylene particles which is followed by grafting through extrusion or radiation which in turn is followed by exposure to and/or development of water to obtain cross-linking. A catalyst is added preferably by mixing polyethylene powder with the catalyst and adding that powder to the powder with diffused silane, after that diffusion has been completed.

Abstract: Disks are cut from copper or a copper alloy which can be precipitation-hardened. A copper alloy powder is prepared and dispersion-hardened. The disks are assembled in a stack and alternate with powder layers and extruded. Subsequent heat treatment of the extruded product strengthens it throughout. The method is used specifically to make a hardened copper alloy to be used for making electrodes for resistance welding.

Abstract: A method of making a wave guide by electrolytically depositing copper on a mandrel is improved by using, e.g., a nickel steel mandrel having a thermal coefficient of expansion about one-tenth or less of that of copper. After plating, the assembly is heated so that the copper tube separates from the mandrel without sticking, and can be taken off without exercise of undue force, which could damage mandrel or tube.

Abstract: A seamless pipe made by extrusion or piercing and having eccentric interior has the outside of one of its ends turned to concentric dimensions with its interior and is pulled through a peeling and scraping tool affixed to a positioning die, and over a mandrel which widens the pipe particularly in the zone of peeling.