Nickel-Aluminium Bronze Propellers & Marine Castings
镍铝青铜螺旋桨与海工铸件
标签：螺旋桨, 镍铝青铜, 船舶, 空蚀
船舶螺旋桨主流材料为镍铝青铜 NAB（Cu 79–82%、Al 8.5–11%、Ni 4–5.5%、Fe 3–5%，如 ASTM B148 C95800），耐海水空蚀优于锰黄铜。大桨（直径 5 m 以上）以砂型或陶瓷型分瓣浇注，浇温 1180–1200℃，凝固后对桨叶做荧光渗透与超声探伤。热处理 675℃±25℃ 保温后控冷可抑制脱铝腐蚀。某修船厂铸造 2.4 m 桨重 1.8 t，加工后静平衡误差控制在 50 g 以内，寿命为锰黄铜桨的 1.5–2 倍。
Marine propellers use nickel-aluminium bronze NAB (Cu 79–82%, Al 8.5–11%, Ni 4–5.5%, Fe 3–5%, e.g. ASTM B148 C95800), outperforming manganese brass against seawater cavitation. Large wheels (5 m+) are cast in sectional sand or ceramic molds at 1180–1200°C, then blades undergo fluorescent penetrant and ultrasonic inspection. Heat treating at 675°C ±25°C with controlled cooling suppresses dealuminization. A repair yard cast a 2.4 m, 1.8 t prop holding static balance within 50 g — 1.5–2× the life of manganese-brass props.