| 摘要 |
PROBLEM TO BE SOLVED: To provide an aluminum extrusion having an etching surface with an excellent surface property, and to provide a surface treatment method for the same.SOLUTION: An aluminum extrusion containing 0.02-1.0 wt.% zinc of which surface consists of an etching surface is characterized in that, on the surface of the aluminum extrusion, an average value of height difference between two adjacent planes across a crystal grain boundary of aluminum is 1 μm or less. The aluminum extrusion can be obtained by etching treatment using an alkaline etching liquid containing sodium nitrate. |
