In a method, an aluminum body is chemically treated with at least one of an alkaline solution and an acid solution. Anode-oxidization is performed on the chemically treated aluminum body to form an aluminum oxide layer. The aluminum oxide layer is treated with hot water at a temperature more than 75° C. or steam. The aluminum oxide layer after being treated with hot water or steam includes plural columnar grains, and an average width of the columnar grains is in a range from 10 nm to 100 nm.

A medical scope device such as an endoscope is produced using a cast aluminum process including a molten casting aluminum alloy including a maximum of 0.2 - 0.3% Si and at least 5% Zn. The process includes providing an investment casting mold, casting the aluminum alloy in the mold to create a component and removing the mold from the component, post-machining the component to meet a desired specification, and after post-machining the component, performing surface finishing, such as centrifugal barrel finishing (CBF) sufficient to remove impurities on casting surfaces by 2 - 3 mils, then coating the component with a micro-crystalline aluminum anodic coating of at least 0.5 mil thickness. A medical scope and product-by-process is also provided employing such techniques.

An aluminum member (1) includes: a base material (2) composed of aluminum or an aluminum alloy; and an anodic oxide film (3) formed on a surface of the base material. The anodic oxide film includes: an amorphous layer (31), which is composed of an amorphous aluminum oxide and is formed on the base material (2); and a crystal layer (32), which is composed of a crystalline aluminum oxide and is formed on the amorphous layer (31). The aluminum member (1) can be obtained by forming the anodic oxide film (3) on the base material (2) by performing an anodization process on the base material (2) in an electrolytic solution, which contains boron atoms and has a pH of 7.0-12.0.

Anodic oxide coatings that provide corrosion resistance to parts having protruding features, such as edges, corners and convex-shaped features, are described. According to some embodiments, the anodic oxide coatings include an inner porous layer and an outer porous layer. The inner layer is adjacent to an underlying metal substrate and is formed under compressive stress anodizing conditions that allow the inner porous layer to be formed generally crack-free. In this way, the inner porous layer acts as a barrier that prevents water or other corrosion-inducing agents from reaching the underlying metal substrate. The outer porous layer can be thicker and harder than the inner porous layer, thereby increasing the overall hardness of the anodic oxide coating.

Anodic oxide coatings that provide corrosion resistance to parts having protruding features, such as edges, corners and convex-shaped features, are described. According to some embodiments, the anodic oxide coatings include an inner porous layer and an outer porous layer. The inner layer is adjacent to an underlying metal substrate and is formed under compressive stress anodizing conditions that allow the inner porous layer to be formed generally crack-free. In this way, the inner porous layer acts as a barrier that prevents water or other corrosion-inducing agents from reaching the underlying metal substrate. The outer porous layer can be thicker and harder than the inner porous layer, thereby increasing the overall hardness of the anodic oxide coating.

According to various embodiments of the present disclosure, an electronic device may comprise a housing including a front plate and a rear plate and a display. At least one of the front plate or the rear plate may include a plate exposed to an outside. The plate may include a metal member including a first metal and an oxide layer formed on at least one surface of the metal member. The metal member may comprise a first portion including irregularities formed by at least one second metal included in a first solution, the at least one second metal being substituted for the a portion of the metal member, the at least one second metal being removed from the metal member by the first solution and a flat second portion etched by the first solution.

According to various embodiments of the present disclosure, an electronic device may comprise a housing including a front plate and a rear plate and a display. At least one of the front plate or the rear plate may include a plate exposed to an outside. The plate may include a metal member including a first metal and an oxide layer formed on at least one surface of the metal member. The metal member may comprise a first portion including irregularities formed by at least one second metal included in a first solution, the at least one second metal being substituted for the a portion of the metal member, the at least one second metal being removed from the metal member by the first solution and a flat second portion etched by the first solution.

Aluminium alloys suitable for etched and anodized components, in particular aluminum extrusion alloys of the types containing Magnesium and Silicon, which after being extruded to any wide variety of forms for different applications such as house buildings and other building applications is subjected to etching in a conventional alkaline etching bath and subsequent anodizing, wherein the relation between Cu and Zn is controlled to avoid preferential grain etching and the ratio of Cu/Zn is below 1.

According to various embodiments of the disclosure, an electronic device may include: a housing, a processor disposed inside the housing, the housing may include a metal member comprising a metal and including a first convex and concave pattern formed in a shape corresponding to a shape of a second convex and concave pattern formed on a jig, wherein the jig is formed for use in electro chemical machining (ECM), and the first convex and concave pattern may have at least a portion formed at a substantially uniform pitch and a substantially uniform height.

The present invention provides: a lightweight optical member which can be produced at relatively low cost and which provides low reflectance, stability upon exposure to light, and abrasion resistance; and an efficient method for producing such an optical member. An optical member according to the present invention is characterized by comprising: a metallic base material; a low-reflective treatment layer formed on the surface of the metallic base material; and a silica layer formed on the surface of the low-reflective treatment layer. It is preferable for the silica layer to have a layer thickness of 0.1-10 μM.