双相不锈钢(DSS)具有良好的机械性能和耐腐蚀性,并在科学技术领域引起了越来越多的关注。然而,N和Cr含量的增加,Mo,等。,由于DSS中的合金元素增加了生产难度。特别是,N元素增加了Cr2N沉淀的风险,这会严重恶化DSS的热塑性,同时增加它的力量。出于这个原因,为了适应增材制造工艺,设计了低N含量的25Cr型DSS。关于纳米夹杂物的氧化物沉淀和有效的晶粒细化,并考虑到选择性激光熔化制造的好处,低N25Cr型双相不锈钢,重量为0.09。%N含量取得了较高的力学性能,屈服强度为712兆帕,伸长率为27.5%,V型缺口冲击韧性为160J/cm2。将详细讨论微观结构的演变以及机械性能改善背后的原因。
Duplex stainless steel (DSS) exhibits good mechanical properties and corrosion resistance, and has attracted more and more attention within the fields of both science and technology. However, the increasing levels of N and of Cr, Mo, etc., as alloying elements in DSS increase production difficulty. In particular, the N element increases the risk of Cr2N precipitation, which can seriously deteriorate the thermal plasticity of DSS, while increasing its strength. For this reason, a low-N-content 25Cr-type DSS was designed in order to adapt additive manufacturing processes. With regard to the nano-inclusions of oxide precipitation and effective grain refinement, and considering the benefits of selective laser melting fabrication, a low-N 25Cr-type duplex stainless steel with a 0.09 wt.% N content achieved high mechanical properties, with a yield strength of 712 MPa and an elongation of 27.5%, while the V-notch impact toughness was 160 J/cm2. The microstructure evolution and the reasons behind the improvement in mechanical properties will be discussed in detail.