ALUMINUM ALLOY PIPE WITH SUPERIOR CORROSION RESISTANCE AND PROCESSABILITY, AND METHOD FOR MANUFACTURING SAME

• Main Authors: SUZUKI Taichi, HATTA Hidenori, ISHIZAKA Takumi
• Format: Patent
• Language: English; French; German
• Published: 07.02.2018
• Subjects: ALLOYS; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKINGWITHOUT ESSENTIALLY REMOVING MATERIAL; CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS ANDNON-FERROUS ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES,OTHERWISE THAN BY ROLLING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METALLURGY; PERFORMING OPERATIONS; PUNCHING METAL; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS

An aluminum alloy pipe produced by porthole extrusion includes: Mg at a concentration equal to or higher than 0.7% (mass%, the same applies hereinafter) and lower than 1.5%; Ti at a concentration higher than 0% and equal to or lower than 0.15%; with the balance being Al and unavoidable impurities. As the unavoidable impurities, Si has a limited concentration of 0.20% or lower, Fe 0.20% or lower, Cu 0.05% or lower, Mn 0.10% or lower, Cr 0.10% or lower, and Zn 0.10% or lower. Difference between the maximum value and the minimum value of the Mg concentration in a lengthwise direction of the pipe is 0.2% or lower, and the average crystal grain size in a cross-section perpendicular to the lengthwise direction is 300 µm or smaller. An aluminum alloy pipe used for piping or hose joints and having excellent strength, corrosion resistance, and processability can be provided.