In this study, bulk samples of a CrMoNbWV high-entropy alloy (HEA) were obtained for the first time by spark plasma sintering (SPS) of mechanically alloyed (MA) powders at 1200 °C, 1300 °C, and 1400 °C. Microstructure evolution, phase formation as well as wear and corrosion behavior were investigated. The MA powders’ phase composition was found to be represented by body-centered-cubic (BCC) solid solution. The solid solution partially decomposed to Laves phases under the sintering, such as Cr2Nb and (Fe, Cr)Nb, and NbVO4-VO oxides mixture. The temperature increase to 1400 °C led to a grain coarsening of the BCC phase and decreased the Laves phase content accompanied by precipitation at the grain boundaries. The sintered samples showed high hardness and compressive strength (2700–2800 MPa) at room temperature. The wear tests demonstrated excellent results in comparison to conventional wear-resistant composites. The obtained samples also exhibited high corrosion resistance under electrochemical tests in H2SO4 solution. The CrMoNbWV HEA has comparable mechanical and corrosive properties with the WNbMoTaV type HEA, but at the same time has a reduced density: CrMoNbWV—10.55 g/cm3, WNbMoTaV—12.42 g/cm3@en

16Cr-2Ni-Mn-Mo-xN (wt%) stainless steel powders were synthesized by mechanical alloying from elemental metal and chromium nitride (Cr2N) powders. Compaction of resulting powders was carried out using spark plasma sintering technology. The X-Ray diffraction and Scanning Electron Microscopy analysis showed that chemical homogeneity improves with increasing alloying time and decreasing nitrides powder content. Analysis of sintering samples showed the formation of a and ?-phase solid solution with nitrogen-containing samples containing undissolved nitrogen inclusions. The results of high-temperature tensile tests showed an increase of tensile stress for the sample containing 50% Cr2N. Furthermore, the microhardness was increased with an increase in the amount of Cr2N.

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Conventional manufacturing of titanium intermetallic alloys is associated with brittleness, hard machinability and, consequently, the high cost, which makes additive manufacturing a promising way of producing complex intermetallic parts. At the same time, γ-TiAl alloys exhibit good high temperature strength, fatigue, and oxidation resistance. In the present study the gamma-based alloy spherical powders were prepared by mechanical alloying from elemental powders followed by the plasma spheroidization process. Microstructure and phase composition of the produced powders were studied after different milling times in a planetary mill. The optimally milled powders were treated in the flow of thermal plasma to obtain powder particles with a high degree of sphericity. The produced spherical powders were used in Selective Laser Melting (SLM) process with high preheating temperatures to obtain crack-free intermetallic samples. The microstructure and phase composition of the SLM-ed TiAl-samples were investigated with regard to different process parameters.

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In this paper, laser powder-bed fusion (L-PBF) additive manufacturing (AM) with a high-temperature inductive platform preheating was used to fabricate intermetallic TiAl-alloy samples. The gas atomized (GA) and mechanically alloyed plasma spheroidized (MAPS) powders of the Ti-48Al-2Cr-2Nb (at. %) alloy were used as the feedstock material. The effects of L-PBF process parameters-platform preheating temperature-on the relative density, microstructure, phase composition, andmechanicalproperties ofprintedmaterialwere evaluated. Crack-free intermetallic samples with a high relative density of 99.9% were fabricated using 900 °C preheating temperature. Scanning electron microscopy and X-Ray diffraction analyses revealed a very fine microstructure consisting of lamellar α₂/γ colonies, equiaxed γ grains, and retained β phase. Compressive tests showed superior properties of AM material as compared to the conventional TiAl-alloy. However, increased oxygen content was detected inMAPS powder compared to GA powder (~1.1 wt. % and ~0.1 wt. %, respectively), which resulted in lower compressive strength and strain, but higher microhardness compared to the samples produced from GA powder.

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The paper presents the results of the composition, structure and mechanical characteristics of heat-resistant iron based alloy samples produced by laser cladding. The samples were manufactured using secondary raw material (chips), which were converted into powder by plasma spheroidization. The crystalline transformations for the as-processed as well as after several heat treatment conditions were analyzed. Phase, chemical composition and mechanical characteristics were investigated.

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