Abstract

The effect of liquid nitrogen (LN) cryogenic cooling during gas metal arc directed energy deposition (DED) additive manufacturing (AM) of nickel aluminum bronze (NAB) was investigated. A commercially available LN spray cooling system was incorporated into the DED process for interpass temperature control and duty cycle optimization. Reductions in total build time and distortion were measured for single-bead wall and multi-layer block deposits. Strength and ductility requirements of the NAB wire and base material were met. In agreement with experimental results, coupled thermal-mechanical finite element analysis of DED AM with an active cooling source predicted a reduction in build time, and in residual stress build-up and distortion. Overall, the results of this study demonstrate that LN cryogenic cooling can be used to control interpass temperature without adversely affecting NAB build properties and offers opportunities for immediate transition into NAB DED applications.

中文翻译：

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液氮深冷冷却对镍铝青铜丝电弧定向能量沉积的影响

摘要

研究了镍铝青铜 (NAB) 气相金属电弧定向能量沉积 (DED) 增材制造 (AM) 过程中液氮 (LN) 低温冷却的效果。 DED 工艺中采用了商用液氮喷雾冷却系统，用于层间温度控制和占空比优化。对于单珠壁和多层块沉积，测量了总构建时间和变形的减少。满足 NAB 线材和基材的强度和延展性要求。与实验结果一致，采用主动冷却源的 DED AM 的热机械耦合有限元分析预测，构建时间会减少，残余应力积聚和变形也会减少。总体而言，这项研究的结果表明，液氮低温冷却可用于控制层间温度，而不会对 NAB 构建性能产生不利影响，并为立即过渡到 NAB DED 应用提供了机会。