In recent years, arc-based additive manufacturing techniques have been enthusiastically accepted for fabricating components made of various structural materials. In this work, a functionally graded material (FGM) structure of pure copper (Cu) and stainless steel (SS316L) was developed using cold metal transfer-based wire arc additive manufacturing (CMT-WAAM). Components combining Cu and steel show great usage in many industries since they combine high corrosion resistance, ductility, thermal conductivity, and wear resistance to the excellent mechanical properties. The CMT-WAAM fabricated FGM was well built and shows no deformation, bulging, and cracking in the graded region. Microstructural and elemental mapping analysis studies shows that Fe was deposited over Cu matrix in the gradient region and a gradual grain size and compositional gradient was observed. The phase analysis doesn’t reveal formation on any metastable or intermetallic phase at the interface. The mechanical properties of the printed structure were analyzed by room temperature tensile testing, Charpy impact test and microhardness measurements in both scanning and build directions. The FGM samples show an average ultimate tensile strength of 641 ± 10.06 MPa vs 427 ± 5.03 MPa and elongation to fracture percentage of 19.8 ± 1.13% vs 21.8 ± 1.56% in scanning and build directions, respectively. The average Charpy toughness of fabricated FGM was 57.88 ± 2.86 J vs 46.24 ± 1.46 J in scanning and build directions, respectively. The tensile and impact strengths of FGM samples were higher than as fabricated pure Cu samples but lower than as fabricated SS316L samples and the fracture was dominated by ductile mode of fracture. The strength and ductility of CMT-WAAM fabricated SS316L-Cu FGM was significantly high and may allow use of these materials in engineering and industrial applications.

中文翻译：

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电弧增材制造SS316L-Cu功能梯度材料的微观结构和机械性能检查

近年来，基于电弧的增材制造技术已被广泛接受，用于制造由各种结构材料制成的部件。在这项工作中，使用基于冷金属转移的电弧增材制造 (CMT-WAAM) 开发了纯铜 (Cu) 和不锈钢 (SS316L) 的功能梯度材料 (FGM) 结构。铜和钢相结合的部件在许多行业中得到广泛应用，因为它们结合了高耐腐蚀性、延展性、导热性和耐磨性以及优异的机械性能。 CMT-WAAM 制造的 FGM 构建良好，分级区域没有变形、膨胀和裂纹。微观结构和元素图分析研究表明，Fe 沉积在梯度区域的 Cu 基体上，并且观察到逐渐的晶粒尺寸和成分梯度。相分析没有揭示界面处任何亚稳态或金属间相的形成。通过室温拉伸测试、夏比冲击测试以及扫描和构建方向上的显微硬度测量来分析打印结构的机械性能。 FGM 样品在扫描和构建方向上的平均极限拉伸强度分别为 641 ± 10.06 MPa 和 427 ± 5.03 MPa，断裂伸长率分别为 19.8 ± 1.13% 和 21.8 ± 1.56%。制造的 FGM 的平均夏比韧性在扫描和构建方向上分别为 57.88 ± 2.86 J 和 46.24 ± 1.46 J。 FGM 样品的拉伸强度和冲击强度高于制造的纯铜样品，但低于制造的 SS316L 样品，并且断裂以延性断裂模式为主。 CMT-WAAM 制造的 SS316L-Cu FGM 的强度和延展性非常高，可以允许在工程和工业应用中使用这些材料。