Abstract:
The present invention relates to a lubricant composition for press-forming an aluminum or aluminum alloy sheet at low temperatures. The composition contains a component (a): 45 to 90% by weight of one or more hydrocarbons selected from the group consisting of mineral oils, synthetic naphthenes, polybutenes, and poly(mono).alpha.-olefins, and component (b): 10 to 45% by weight of one or more C10-C24 linear or branched fatty alcohols. The ester value of the composition is not more than 70, and the kinematic viscosity is less than 20 cSt at 40.degree. C. When this composition is used in forming aluminum or aluminum alloy sheets, enhanced formability can be obtained, and shapes which could not obtained conventionally can be formed.
Abstract:
Lubricants are provided which are aluminium or aluminium alloy plate moulding lubricants, and are lubricants which are easily removed after moulding of aluminium or aluminium alloy plate and assembly; also, bonding and welding can be performed while coated with those lubricants, and the bonding and weld strength obtained are the same as if there were no adhering lubricant. Their main constituents are a polyalkylene oxide or derivative thereof and a higher fatty acid salt. It is preferable if they contain 50 to 2 weight % polyalkylene oxide or derivative thereof, and the ratio of higher fatty acid salt and polyalkylene oxide or derivative thereof is within the range 1/12 to 1/4, and further that they contain water. When these lubricants are formed into a 0.2-2.0 g/m.sup.2 solid film on the surface of the aluminium or aluminium alloy plate, this is suitable for moulding processes.
Abstract:
A blank for magnetic hard disk and a method for producing the same are provided, characterized in that the attachment or adhesion of a blank of a disk shape to each other can be prevented when such blank is stacked together for disk annealing, thereby improving the productivity of magnetic hard disk, and that the damage of blank surface can be prevented during blanking. Firstly, an aluminium alloy plate is subjected to continuous surface washing process with an etching solution while winding off the aluminium alloy plate in a coil, whereby the oxide film on the surface of the aluminium alloy plate is removed to concurrently deposit insoluble smut on the surface. Then, the aluminium alloy plate after the washing process is pressed for blanking thereof into a blank of a disk shape.