Due to the aging hardening nature of Cu-15 Ni-8Sn alloy, it is necessary to investigate the effect of aging on the properties of SLM-manufactured Cu-15 Ni-8Sn alloy. In the present work, first, microstructural evolution of the alloys that underwent the direct aging treatment, solution treatment, and solution treatment plus aging are investigated in detail using scanning electron microscopy (SEM) and transmission electron microscopy (TEM); and second, mechanical properties and electrical conductivity of these samples were measured. After solution treatment, it’s found that fine Sn-enriched precipitates resolved in matrix, an abundance of dislocation diminished, the grain size increased and a number of annealing twins formed. Spinodal decomposition could happen during the cooling of solution-treatment. According to the comparison of the microstructure and performance of the printed sample and the solution treated sample after aging, it’s concluded that the strength and conductivity of the aged SLM-manufactured samples are higher than that of the aged solution-treatment samples for same aging duration, however, the plasticity and aging strengthening effect is inverted. The sharp decrement of plasticity is mainly ascribed to network discontinuous precipitations (DPs) in the grain boundary, but not the lamellar DPs. Annealing twin boundaries depressed the formation of DPs in the grain boundary, and improved the plasticity of aged solution-treatment samples. Lamellar DPs were also considered to be enhanced the strength of aged samples, besides modulated structures, D0₂₂ phase and L1₂ phase.

由于Cu-15 Ni-8Sn合金的时效硬化性质，有必要研究时效对SLM制造的Cu-15 Ni-8Sn合金性能的影响。在本工作中，首先，使用扫描电子显微镜（SEM）和透射电子显微镜（TEM）详细研究了经过直接时效处理，固溶处理以及固溶处理和时效处理的合金的微观组织演变；其次，测量这些样品的机械性能和电导率。经过固溶处理后，发现富集了细小锡的沉淀物在基体中分解，位错数量减少，晶粒尺寸增大，并形成了许多退火孪晶。在溶液处理冷却过程中可能发生旋节线分解。通过比较老化后印刷样品和固溶处理样品的微观结构和性能，可以得出结论，在相同的老化时间下，老化的SLM制造的样品的强度和电导率要高于老化的固溶处理的样品。但是，可塑性和时效强化效果相反。可塑性的急剧下降主要归因于晶界中的网络不连续沉淀（DPs），而不是层状DPs。退火双晶界抑制了晶界中DP的形成，并改善了时效固溶处理样品的可塑性。除调节结构D0外，还认为层状DP可以增强老化样品的强度 结论是，在相同的老化时间下，老化的SLM制造的样品的强度和电导率均高于老化的固溶处理样品，但是可塑性和老化增强效果却相反。可塑性的急剧下降主要归因于晶界中的网络不连续沉淀（DPs），而不是层状DPs。退火双晶界抑制了晶界中DP的形成，并改善了时效固溶处理样品的可塑性。除调节结构D0外，还认为层状DP可以增强老化样品的强度 结论是，在相同的老化时间下，老化的SLM制造的样品的强度和电导率均高于老化的固溶处理样品，但是可塑性和老化增强效果却相反。可塑性的急剧下降主要归因于晶界中的网络不连续沉淀（DPs），而不是层状DPs。退火双晶界抑制了晶界中DP的形成，并改善了时效固溶处理样品的可塑性。除调节结构D0外，还认为层状DP可以增强老化样品的强度 可塑性的急剧下降主要归因于晶界中的网络不连续沉淀（DPs），而不是层状DPs。退火双晶界抑制了晶界中DP的形成，并改善了时效固溶处理样品的可塑性。除调节结构D0外，还认为层状DP可以增强老化样品的强度 可塑性的急剧下降主要归因于晶界中的网络不连续沉淀（DPs），而不是层状DPs。退火双晶界抑制了晶界中DP的形成，并改善了时效固溶处理样品的可塑性。除调节结构D0外，还认为层状DP可以增强老化样品的强度₂₂相和L1 ₂相。