| 摘要 |
PROBLEM TO BE SOLVED: To impart excellent corrosion resistance and terminal workability to the material by preparing an aluminum piping material having a compsn. contg. each specified amt. of Cu, Mn and Cr, and in which each content of Si and Fe as inevitable impurities is controlled. SOLUTION: An aluminum piping material for a heat exchanger having a compsn. contg., by weight, 0.1 to 0.5% Cu, 0.4 to 0.6% Mn and 0.1 to 0.3% Cr, in which each content of Si and Fe as inevitable impurities is controlled to <=0.2%, and the balance Al with other inevitable impurities is prepd. Cu promotes facial corrosion to suppress the generation of pitting corrosion, furthermore dulls its intergranular corrosion sensitivity to improve the corrosion resistance thereof and moreover contributes to the improvement of its strength. Mn is bonded with Fe to form an Al6(MnFe) compd., by which it educes crystallized products such as Al3Fe, Al6Fe or the like causing pitting corrosion as a cathode and suppresses the progression of pitting corrosion. Cr improves its pitting corrosion resistance and strength, and the regulations of Si and Fe make pitting corrosion hard to be generated.
|
