Stoudt M R, Ricker R E, Lass E A, Levine L E
Materials Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899.
JOM (1989). 2017 Mar;69(3):506-515. doi: 10.1007/s11837-016-2237-y. Epub 2017 Jan 9.
The additive manufacturing (AM) build process produces a segregated microstructure with significant variations in composition and phases that are uncommon in traditional wrought materials. As such, the relationship between the post-build microstructure and the corrosion resistance is not well understood. Stainless steel alloy 17-4PH is an industrially-relevant alloy for applications requiring high-strength and good corrosion resistance. A series of potentiodynamic scans conducted in a deaerated 0.5 mol/L NaCl solution evaluated the influence of these microstructural differences on the pitting behavior of SS17-4. The pitting potentials were found to be higher in the samples of additively-processed material than in samples of the alloy in wrought form. This indicates that the additively-processed material is more resistant to localized corrosion and pitting in this environment than the wrought alloy. The results also suggest that after homogenization, the additively-produced SS17-4 could be more resistant to pitting than wrought SS17-4 in an actual service environment.
增材制造（AM）构建过程会产生一种成分和相存在显著差异的偏析微观结构，这在传统锻造材料中并不常见。因此，构建后微观结构与耐腐蚀性之间的关系尚未得到很好的理解。17-4PH不锈钢合金是一种在工业上相关的合金，适用于需要高强度和良好耐腐蚀性的应用。在脱气的0.5 mol/L NaCl溶液中进行的一系列动电位扫描评估了这些微观结构差异对SS17-4点蚀行为的影响。结果发现，增材加工材料样品的点蚀电位高于锻造形式合金的样品。这表明，在这种环境下，增材加工材料比锻造合金更耐局部腐蚀和点蚀。结果还表明，经过均匀化处理后，增材制造的SS17-4在实际使用环境中可能比锻造的SS17-4更耐点蚀。
