Anodized aluminum alloy material having both durability and low polluting property

Abstract

An anodized aluminum alloy material is formed of an aluminum alloy having a Mg content between 0.1 and 2.0% by mass, a Si content between 0.1 and 2.0% by mass, a Mn content between 0.1 and 2.0% by mass, and an Fe, a Cr and a Cu content of 0.03% by mass or below and containing Al and unavoidable impurities as other components, and is coated with an anodic oxide film. Parts of the anodic oxide film at different positions with respect to thickness of the anodic oxide film have different hardnesses, respectively, and the difference in Vickers hardness between a part having the highest hardness and a part having the lowest hardness is Hv 5 or above.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to an aluminum alloy material and, more particularly, to an anodized aluminum alloy material intended for forming members of the vacuum chambers of apparatuses for manufacturing semiconductor devices and liquid crystal devices, such as CVD systems, PVD systems, ion-implanting systems, sputtering systems and dry etching systems, and those placed in the vacuum chambers.[0003]2. Description of the Related Art[0004]Reactive gases, etching gases, and corrosive gases containing halogen as a cleaning gas are supplied into the vacuum chambers of apparatuses for manufacturing semiconductor devices and liquid crystal devices, such as CVD systems, PVD systems, ion-implanting systems, sputtering systems and dry etching systems. Therefore, the vacuum chambers are required to have corrosion resistance to corrosive gases (hereinafter, referred to as “corrosive gas resistance”). Since a halogen plasma is o...

AI Technical Summary

Benefits of technology

[0010]The present invention has been made in view of the foregoing problems and it is therefore an object of the present invention to provide an anodized aluminum alloy having a high hardness, durability and low polluting property.

[0012]The anodized aluminum alloy material has a high hardness, durability and low polluting property.

[0013]In the anodized aluminum alloy material in the first aspect of the present invention, the hardness of the part having the lowest hardness of the anodic oxide film is Hv 365 or above, which leads to improvement of plasma resistance.

[0014]The aluminum alloy forming the anodized aluminum alloy material has a Mg content between 0.1 and 2.0%, a Si content between 0.1 and 2.0%, a Mn content between 0.1 and 2.0%, and an Fe, a Cr and a Cu content of 0.03% or below and contains Al and unavoidable impurities as other components, the anodized aluminum alloy material is coated with the anodic oxide film, parts of the anodic oxide film at different positions with respect to the thickness of the anodic oxide film have different hardnesses, respectively, and the difference in Vickers hardness between a part having the highest hardness and the part having the lowest hardness of the anodic oxide film is Hv 5 or above. Therefore, the anodized aluminum alloy material has a high hardness, durability and low polluting property.

Problems solved by technology

However, those properties are still unsatisfactory and further improvement of those properties is desired.

Although the plasma resistance may be improved simply by coating an aluminum or an aluminum alloy material with a hard anodic oxide film, the hard anodic oxide film is liable to crack.

However, such an anodic oxide film is harder, and the crack resistance and durability of such an anodic oxide film are worse.