海水泵阀用新型铸造铜合金的研制

Development of a Novel Casting Cu Alloy for Seawater Pumper and Valves

研制了一种海水泵阀用新型铸造铜合金 ,该合金综合力学性能优良 :σb≥ 5 5 0MPa ,σ0 .2 ≥ 2 80MPa ,δ5≥ 18% ;耐海水腐蚀性能优异 ,在 7m/s的天然海水冲刷下 ,腐蚀率低于 0 .0 42mm/a ,在 3 .5m/s的含砂海水冲刷下 ,腐蚀率为0 .14 4mm/a ;与目前推广使用的海水管系材料B10的腐蚀电位相差较小 ,电偶腐蚀率为 0 .0 0 92mm/a ,能有效抑制海水管系的电流腐蚀 ,提高海水泵阀的使用寿命。与国内海水泵阀常用的铜合金相比 ,该合金具有较高的拉伸强度和屈强比 ,能承受较高的压力 ,在深海工程等领域也有广泛的应用前景。

A new cast copper alloy with excellent comprehensive mechanical properties of σ b≥550 MPa ,σ 0.2≥280 MPa,δ 5≥18% and a excellent corrosion resistance to seawater used for seawater pumper and valves was developed. In the seawater with a velocity of 7 m/s, the errosion rate of the alloy is 0.042 mm/a while in the sand-contained seawater with a velocity of 3.5 m/s, the errosion rate is only 0.144 mm/s. The difference of corrosion potentials between the developed alloy and (10/90) Cu-Ni alloy used for widely the seawater pump and valves is less than 100mV with a galvanic corrosion rate of 0.009 2 mm/a, which can effectively restrain galvanic corrosion of seawater pump and raise the service life of the pump and valves. Compared with other conventional copper for seawater pump and valves, the alloy subjeted to higher pressure possesses higher tensile strength and yield-strength ratio so that it can be widely used for the fields, such as deep-sea engineering.