| 摘要 |
A pressure resistant and corrosion resistant copper alloy contains 73.0 mass% to 79.5 mass% of Cu and 2.5 mass% to 4.0 mass% of Si with a remainder composed of Zn and inevitable impurities, in which the content of Cu [Cu] mass% and the content of Si [Si] mass% have a relationship of 62.0‰¤[Cu]-3.6×[Si]‰¤67.5. In addition, the area fraction of the ± phase "±"%, the area fraction of a ² phase "²"%, the area fraction of a ³ phase "³"%, the area fraction of the º phase "²"%, and the area fraction of a µ phase "µ"% satisfy 30‰¤"±"‰¤84, 15‰¤"º"‰¤68, "±"+"º"‰¥92, 0.2‰¤"º"/"±"‰¤2, "²"‰¤3, "µ"‰¤5, "²"+"µ"‰¤6, 0‰¤"³"‰¤7, and 0‰¤"²"+"µ"+"³"‰¤8. |
