The discoloration resistant copper alloy includes: 17-34 mass% of Zn 0.01-2.5 mass% of Sn 0.005-1.8 mass% of Al 0.0005-0.030 mass% of Pb and the balance Cu and inevitable impurities. The composition of the copper alloy satisfies 24 [Zn]+5×[Sn]+3×[Al]40, and 1.2 [Sn]+2×[Al]4.0. The copper alloy satisfies 02×(γ)+(β) 1.5, (γ) being the area ratio (%) of a γ phase and (β) being the area ratio (%) of a β phase in the α phase matrix. The copper alloy has 0-0.7 % of the γ phase and 0-0.9 % of the β phase in the α phase matrix in the area ratio.本發明提供一種耐變色性銅合金及銅合金構件。本發明的耐變色性銅合金含有17~34mass%的Zn、0.01~2.5mass%的Sn、0.005~1.8mass%的Al及0.0005~0.030mass%的Pb,剩餘部份包含Cu及不可避免雜質,該等元素的含量之間具有24〔Zn〕+5×〔Sn〕+3×〔Al〕40、及1.2〔Sn〕+2×〔Al〕4.0的關係,前述耐變色性銅合金被設為如下金屬組織:α相基體的γ相的面積率(γ)%與β相的面積率(β)%之間具有02×(γ)+(β)1.5的關係,並且在α相基體中分散有以面積率計為0~0.7%的γ相及0~0.9%的β相。
