Showa Aluminum Corporation

Yutaka Kato

Eizo Isoyama

Kenji Tsukamoto

A process for preparing a hollow aluminum extrudate for use in a vacuum characterized in that dry air or pure oxygen is supplied to the hollow portion of the shaped material being extruded. During the extrusion, the inner surface of the extrudate defining the hollow portion is held out of contact with the atmospheric air containing water to form a compact oxide coating on the inner surface without permitting formation of any hydrated oxide coating.

Process for preparing hollow aluminum extrudates for use in vacuum

A hollow extrudate for use in a vacuum is produced by a process comprising the steps of hermetically closing the forward open end of a hollow shaped material immediately after extrusion from a billet, cutting the shaped material after a predetermined length thereof has been subsequently extruded and hermetically closing the cut end at the same time, and cutting off the closed ends. The billet is a composite material composed of a core of aluminum having a high purity of at least 99.9% and an aluminum alloy cladding. The extrudate obtained has an inner layer and an outer layer corresponding to the core and the cladding, respectively.

Process for producing hollow extrudate for use in vacuum

An aluminum material for use in a vacuum is produced by a process comprising the steps of removing a hydrated oxide coating from the surface of a worked aluminum material to obtain a clean surface in a dry state, and heating the aluminum material in an oxygen gas-containing atmosphere out of contact with the water-containing atmosphere to form an oxide coating on the dry clean surface.

Growing community of inventors

Sakai, Japan

Yutaka Kato