Metallic tubes for housing optical fibers and process for producing the same

An optical fiber-housing metal pipe, comprising a base body of said metal pipe, and an Al-based composite layer formed on the surface of said metal pipe base body, said composite layer containing at least one kind of a component selected from the group consisting of a carbide, an oxide and an organic compound.

An optical fiber-housing metal pipe, comprising a base body of the optical fiber-housing metal pipe, a nickel layer formed on the surface of the base body, and an aluminum layer formed on the surface of the nickel layer.

An optical fiber-housing metal pipe, comprising a base body of an optical fiber-housing metal pipe, and an aluminum or aluminum alloy layer formed on the surface of the metal pipe base body, a maximum height (Ry) of said aluminum or aluminum alloy layer being 3 μm or less.

An optical fiber-housing metal pipe, comprising a base body of an optical fiber-housing metal pipe, an Al-X alloy layer formed on the surface of the base body, where X is one or two kinds of elements selected from the group consisting of 0.5 wt % ≦Mn≦50 wt %, 0.1 wt % ≦Ti≦80 wt %, 0.05 wt % ≦Ni≦40 wt %, 1.0 wt % ≦Cr≦30 wt %, 1.0 wt % ≦Nb≦30 wt %, 0.1 wt % ≦Mg≦70 wt %, 0.05 wt % ≦Fe≦20 wt %, 0.05 wt % ≦In≦1.0 wt %, and 0.05 wt % ≦Sn≦1.0 wt %.

An optical fiber-housing metal pipe comprising a base body of an optical fiber-housing metal pipe, an Al-X alloy layer formed on the surface of the base body, where X is one or two kinds of elements selected from the group consisting of 0.5 wt % ≦Mn≦50 wt %, 0.1 wt % ≦Ti≦80 wt %, 0.05 wt % ≦Ni≦40wt %, 1.0 wt % ≦Cr≦30 wt %, 1.0 wt % ≦Nb≦30 wt %, 0.1 wt %. ≦Mg≦70 wt %,0.05 wt % ≦Fe≦20 wt %, 0.05 wt % ≦In≦1.0 wt %, and 0.05 wt % ≦Sn≦1.0wt %

• wherein the base body of the optical fiber-housing metal pipe is stainless steel, and a nickel layer is formed inside the Al-X alloy layer.

An optical fiber-housing metal pipe comprising a base body of an optical fiber-housing metal pipe, an AI-X alloy layer formed on the surface of the base body, where X is one or two kinds of elements selected from the group consisting of 0.5 wt % ≦Mn≦50 wt %, 0.1 wt % ≦Ti≦80 wt %, 0.05 wt % ≦Ni≦40 wt %, 1.0 wt % ≦Cr≦30 wt %, 1.0 wt % ≦Nb≦30 wt %, 0.1 wt % ≦Mg≦70 wt %, 0.05 wt % ≦Fe≦20 wt %, 0.05 wt % ≦In≦1.0 wt %, and 0.05 wt % ≦Sn≦1.0 wt %

• wherein the base body of the optical fiber-housing metal pipe is stainless steel, and a nickel layer 0.02 to 2.5 μm thick is formed inside the Al-X alloy layer.

A method of manufacturing an optical fiber-housing metal pipe excellent in corrosion resistance, comprising:

• the step of forming an aluminum or aluminum alloy layer on the surface of a base body of an optical fiber-housing metal pipe;
• and
• the step of smoothing the aluminum or aluminum alloy layer by drawing said metal pipe.