电弧增材镍铝青铜的组织与性能

Microstructure and mechanical properties of NAB by wire and arc additive manufacturing

镍铝青铜合金由于其在海水中的高耐腐蚀性能、抗生物污染性能和良好的抗空化冲击性能,被广泛运用于船舶螺旋桨的制造,但传统的铸造镍铝青铜由于材料成本过高,并且性能已不再适用于现今越来越高的要求.为了获得性能优异的镍铝青铜构件,采用了电弧增材制造技术成功制造了镍铝青铜合金构件,研究了铸造镍铝青铜和电弧增材的镍铝青铜的微观组织和力学性能的差异.结果表明,与铸态镍铝青铜合金相比,电弧增材制造的镍铝青铜合金有更细小的微观组织,κⅠ相的析出被抑制,绝大多数的β′相转变为α+κⅢ的共析组织,元素分布更均匀.与铸态镍铝青铜相比(545 MPa,20%),电弧增材制造的镍铝青铜构件展现了更加优异的力学性能,极限抗拉强度达到700 MPa,断后伸长率达到38%.

Nickel aluminum bronze alloy(NAB)is extensively utilized in the production of ship propellers because of its high corrosion resistance,resilience against biological fouling,and excellent cavitation erosion resistance in seawater.Nevertheless,conventional cast nickel aluminum bronze is no longer adequate for today's escalating demands,primarily due to its steep material cost and performance that has become outdated.To procure nickel aluminum bronze components possessing outstanding performance,wire and arc additive manufacturing technology was employed to successfully produce nickel aluminum bronze alloy components.A comparative analysis was conducted to examine the disparities in microstructure and mechanical properties between cast nickel aluminum bronze and wire and arc added nickel aluminum bronze.The findings revealed that,in contrast to as-cast nickel aluminum bronze alloy,the wire and arc added variant exhibited a refined microstructure,inhibited precipitation of theκⅠphase,and a significant transformation of theβ'phase into an eutectoid structure consisting ofα+κⅢ,ultimately leading to a more homogenous distribution of elements.When juxtaposed with as-cast nickel aluminum bronze(which has a tensile strength of 545 MPa and a ductility of 20%),the wire and arc added nickel aluminum bronze components demonstrated superior mechanical properties,achieving an ultimate tensile strength of up to 700 MPa and a ductility of 38%.