The Effect of Cu Content and Surface Finish on the Metal Dusting Resistance of Additively Manufactured NiCu Alloys

Abstract

Due to the inhibiting behavior of Cu, NiCu alloys represent an interesting candidate in carburizing atmospheres. However, manufacturing by conventional casting is limited. It is important to know whether the corrosion behavior of conventionally and additively manufactured parts differ. Samples of binary NiCu alloys and Monel Alloy 400 were generated by laser powder bed fusion (LPBF) and exposed to a carburizing atmosphere (20 vol% CO–20% H2–1% H2O–8% CO2–51% Ar) at 620 °C and 18 bar for 960 h. Powders and printed samples were investigated using several analytic techniques such as EPMA, SEM, and roughness measurement. Grinding of the material after building (P1200 grit surface finish) generally reduced the metal dusting attack. Comparing the different compositions, a much lower attack was found in the case of the binary model alloys, whereas the technical Monel Alloy 400 showed a four orders of magnitude higher mass loss during exposure despite its Cu content of more than 30 wt%.

Decreased Metal Dusting Resistance of Ni-Cu Alloys by Fe and Mn Additions

“…The samples were provided by RWTH Aachen and Hochschule Osnabrück. Further details on the manufacturing process can be found elsewhere [5]. Before the MD exposure, the sample surfaces were ground to P1200 grit and cleaned in an ultrasonic bath using ethanol.…”

“…Previous studies hypothesized that a Cu content of at least 20 wt.% in binary Ni-Cu alloys leads to complete inhibition of MD attack [1][2][3][4]. This was recently disproved in experiments on binary Ni-Cu alloys with 50 wt.% Cu [5]. Additionally, low amounts of Fe and Mn additions to the alloy increased the MD attack tremendously [5].…”

“…This was recently disproved in experiments on binary Ni-Cu alloys with 50 wt.% Cu [5]. Additionally, low amounts of Fe and Mn additions to the alloy increased the MD attack tremendously [5]. In commercial Monel Alloy 400 additions of Fe and Mn in combination with C are used to form strengthening carbides [6].…”

A Critical Review of Nanoparticles and Nano Catalyst

“…The hydrogen storage capacity of carbon nanotubes (CNTs) is significantly influenced by their material properties, which are determined by the preparation methods, as stated in the literature by Vozniakovskii, Voznyakovskii, Kidalov, Ovchinnikov, and Kalashnikova [9]. Jahns, Ulrich, Schlereth, Reiff, Krupp, and Galetz [10] conducted research on a new method for preparing NCMs, used the process known as Metal Dusting (MD), which was established.…”

First-principles study of binary austenitic Ni-Cu alloys

“…In this system, a FCC single phase binary alloys spanning the entire concentration range can be produced as a result of a 100% solid solubility in each other. Due to their combination of high strength and toughness, excellent corrosion resistance, and at times reasonable wear resistance, the Ni-Cu alloys are widely used in the marine, chemical and oil industries for manufacturing components [4,7]. However, the ever increasing demand from marine industry for improved performance while keeping material cost low has driven efforts to develop new Ni-Cu-based alloys with enhanced mechanical properties, in particular wear resistance.…”