Porous ceramics can be realized by different methods and are used for various applications such as cross-flow membranes or wall-flow filters, porous burners, solar receivers, structural design elements, or catalytic supports. Within this paper, three different alternative process routes are presented, which can be used to manufacture porous ceramic components with different properties or even graded porosity. The first process route is based on additive manufacturing (AM) of macro porous ceramic components. The second route is based on AM of a polymeric template, which is used to realize porous ceramic components via replica technique. The third process route is based on an AM technology, which allows the manufacturing of multimaterial or multiproperty ceramic components, like components with dense and porous volumes in one complex-shaped component.

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/srin.202100482.

In this study, a novel metal matrix composite based on 60 vol% 316L stainless steel and 40 vol% MgO manufactured by powder metallurgy technology was developed. The corrosion resistance of the developed steel–MgO composite material against molten aluminum alloy AlSi7Mg0.3 was investigated by means of wettability tests and long-term crucible corrosion tests. The wettability tests were carried out using the sessile drop method with the capillary purification technique in a hot-stage microscope (HSM). Static corrosion tests were performed in molten aluminum alloy at 850 °C for 168 h to evaluate the impact of pre-oxidation of the composite surface on the corrosion resistance. The pre-oxidation of steel–MgO composites was carried out at 850 and 1000 °C for 24 h, based on preliminary investigations using thermogravimetry (TG) and dilatometry. The influence of the pre-oxidation on the composite structure, the corrosion resistance, and the phase formation at the interface between the steel–MgO composite and aluminum alloy was analyzed using SEM/EDS and XRD. The impact of the steel–MgO composite material on the composition of the aluminum alloy regarding the type, size, and quantity of the formed precipitations was investigated with the aid of ASPEX PSEM/AFA and SEM/EBSD. It was revealed that the pre-oxidation of the steel–MgO composite at 1000 °C induced the formation of stable MgO-FeO solid solutions on its surface, leading to a significant increase of long-term corrosion resistance against the liquid aluminum alloy.

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The combination of powder metallurgical and ceramics-derived processing enables the manufacturing of innovative metal components. Using high-alloyed transformation-induced plasticity (TRIP) steels facilitates the manufacturing of metal components with outstanding mechanical properties for advanced load applications. The oxygen affinity of some alloying elements promotes the formation of non-metallic particles during sintering, which deteriorate the mechanical properties. Bulk specimens are prepared from a 17Cr7Mn6Ni-TRIP steel powder using a ceramics-derived extrusion process with organic binders at ambient temperature. Processing comprises the thermal binder removal in air and the sintering in pure argon or hydrogen atmospheres. The sintered specimens are analyzed for their amount and composition of non-metallic particles using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The focus of this article is on the automated particle identification and analysis using an automatic SEM-EDS-related device. The automatic feature analysis provides statistical information on the chemistry, size, and morphology. The particles mainly consist of Cr, Mn, Si, and O forming Mn 2 SiO 4 and MnCr 2 O 4. The number of particles mainly depends on the debinding temperature and on the sintering atmosphere. The use of a pure hydrogen sintering atmosphere significantly depresses the formation of MnCr 2 O 4 , whereas silicates remain stable under the applied atmospheric and thermal conditions.