High Relative Density Research Articles

Fabrication of highly transparent AlON ceramics by inhibiting decomposition of AlON

In consolidation of AlON, the extensive decomposition of AlON into α-Al2O3 and AlN during sintering is one of the major reasons that significantly retard its densification process. To accelerate densification of AlON, an ultra-low concentration of La2O3 (0.03 wt%) and Y2O3 (0.02-0.04 wt%) was co-doped as sintering additives to inhibit decomposition of AlON during sintering for fast fabrication of highly transparent AlON ceramics. The phase transformation, microstructure evolution and densification process of the samples undoped and doped additive during heating were studied to investigate the densification mechanism. The results reveal that, compared to the samples undoped additive and single-doped with La2O3, the α-Al2O3 content of the samples co-doped with La2O3 and Y2O3 is significantly deduced at ≤1600 °C, which indicates that the decomposition of AlON is effectively inhibited by co-doping La2O3 and Y2O3. The reduction of α-Al2O3 along with the deceleration effect of La3+ on mass transfer, contributes to more small particles being conserved at high temperatures. Base on this, at later stage of sintering, benefiting from the enhanced mobility of grain boundary by Y3+, AlON ceramics with high relative density (99.79 %) and excellent transparency were obtained via pressureless sintering at 1880 °C for 2.5 h by co-doping 0.03 wt% La2O3 and 0.04 wt% Y2O3. The maximum transmittance of the fabricated AlON ceramics is up to 81.6 % at 3600 nm, and a transmittance of 76.0 % was measured at 400 nm. The ultra-low doping amount of La2O3 and Y2O3 and the high relative density should be the main reasons that lead to the outstanding transparency of the obtained AlON. Additionally, the fabricated AlON ceramics also exhibit a high Vickers hardness of 18.89 ± 0.18 GPa.

Extraction Characterization of Oils Extracted from different Parts of Red and Yellow Varieties of Anacardium occidentale (Lin)

The objective of this study was to extract and characterized the oils from different parts of red and yellow varieties of Anacardium occidentale after extractions using Soxhlet extractor and steam distillation techniques and characterization of the bioactive components using GC/MS analysis. Physicochemical parameters of the extracted oils were analyzed, and the bioactive compositions were also examined. The results showed that the oils extracted were within 0 and 0.5% moisture content and pH values ranged from 3.7 to 4.7. The average relative densities of the extracted oils by Soxhlet extraction and steam distillation at temperature 25oC were 0.887 and 0.8745 g/cm3 respectively, with average saponification value of 132.45 mgKOH/g for Soxhlet extraction and 127.98 mgKOH/g for steam distillation. The iodine values of all the oils were between 35 and 19.00 mg iodine/100g; while the refractive index was between 1.7 and 1.9. The acid values were within the range of 10.00 and 13.00 mgKOH/g, and peroxide value of 1.67 and 1.20 mmol/l. The oils had low viscosity which were within 28 and 32 mpa.s. The compounds identified from the GC-MS results showed that cashew nut shell oil contained cardol, anacardic acid, cardanol, 2-methyl cardol, triacconten and β-sitosterol. The main bioactive components of the extracted oil identified from the stem bark, root bark, and leaf were alkaloids, tannins, flavonoids, coumarins, terpenoids, and saponins. This study, therefore, showed that Soxhlet extraction could be a better extraction method for extraction of oil from cashew nut shell which had higher relative density; while cashew stem bark, root bark and the leaf which had lower density were selective based on the target products.

Li5AlO4-Assisted Low-Temperature Sintering of Dense Li7La3Zr2O12 Solid Electrolyte with High Critical Current Density.

In recent years, solid electrolytes (SEs) have been developed a lot due to the superior safety of solid-state batteries (SSBs) upon liquid electrolyte-based commercial batteries. Among them, garnet-type Li7La3Zr2O12 (LLZO) is one of the few SEs that is stable to lithium anode with high Li+ conductivity and the feasibility of preparation under ambient air, which makes it a promising candidate for fabricating SSBs. However, high sintering temperature (>1200 °C) prevents its large-scale production, further hindering its application. In this work, the Li5AlO4 sintering aid is proposed to decrease the sintering temperature and modify the grain boundaries of LLZO ceramics. Li5AlO4 generates in situ Li2O atmosphere and molten Li-Al-O compounds at relatively low temperatures to facilitate the gas-liquid-solid material transportation among raw LLZO grains, which decreases the densification temperature over 150 °C and strengthens the grain boundaries against lithium dendrites. As an example, Ta-doped LLZO ceramics without excessive Li sintered with 2 wt % Li5AlO4 at 1050 °C delivered high relative density > 94%, an ionic conductivity of 6.7 × 10-4 S cm-1, and an excellent critical current density (CCD) of 1.5 mA cm-2 at room temperature. In comparison, Ta-doped LLZO with 15% excessive Li sintered at 1200 °C delivered low relative density < 89%, a low ionic conductivity of ∼2 × 10-4 S cm-1, and a poor CCD of 0.5 mA cm-2. Li symmetric cells and Li-LFP full cells fabricated with Li5AlO4-assised ceramics were stably cycled at 0.2 mA cm-2 over 2000 h and at 0.8C over 100 cycles, respectively.

Exploring How LPBF process parameters impact the interface characteristics of LPBF Inconel 718 deposited on Inconel 718 wrought substrates

This work investigates the interface properties of LPBF Inconel 718 deposited on Inconel 718 wrought substrates fabricated using the laser powder bed fusion (LPBF) technique. The as-printed (S1, S2, S3, and S4) samples were characterized using optical microscopy (OM),scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and micro-hardness techniques.The samples showed the development of a melted interface zone (MIZ) at the wrought substrate-deposition interface for all processing conditions. The developed interface showed a dendritic grain structure, signifying the remelting of the wrought substrate followed by rapid solidification. The MIZ thickness increased with an increase in laser power and scan speed (28.5 % increase in the MIZ thickness with a ∼ 12 % increase in normalized enthalpy). The assessment of the MIZ showed a high-quality interface. However, with an increase in scanning speed, the density of the MIZ decreases owing to increased porosity and lack-of-fusion (LOF) defects. The S1 condition (250 W and 850 mm/s) resulted in a highly dense part with no visible porosity, LOF defects, and a high relative density (∼99.9 %) in the MIZ region. The S4 condition showed the presence of large porosities and LOF defects at the deposition-MIZ interface, signifying an inferior bond between the deposition and substrate. The microstructural characterization of the LPBF-processed and MIZ region showed an increase in the primary dendritic arm spacing (PDAS) with increasing laser power due to a reduced cooling rate. The micro-hardness characterization of the sample shows a decrease in the hardness of the MIZ attributed to the dissolution of strengthening phases due to remelting. The present work outcome demonstrates the effectiveness of the proposed methodology for manufacturing high-quality parts using LPBF technology.

Superior mechanical properties of a Zr-based bulk metallic glass via laser powder bed fusion process control

Additive manufacturing has made the fabrication of large-dimensioned bulk metallic glasses (BMGs) achievable; however, questions remain regarding how to control the processing parameters to obtain dense and fully amorphous BMGs with desirable mechanical properties. Here, laser powder bed fusion (LPBF) was used to produce dense and fully amorphous Zr59.3Cu28.8Nb1.5Al10.4 BMG samples from two different starting powders within a large processing window of laser powers and scanning speeds. X-ray diffraction (XRD) revealed that fully amorphous XRD patterns were obtained for samples with high relative densities (>99 %) when the LPBF energy density ranged from ∼20 J/mm3 up to ∼33 J/mm3 for coarse powder with low oxygen and up to ∼30 J/mm3 for fine powder with higher oxygen. For the fully XRD amorphous samples, strength and hardness increased with increasing energy density while the relaxation enthalpy and ductility decreased. Transmission electron microscopy revealed that the softer samples contain larger medium range order clusters within the amorphous matrix. With higher LPBF energy density, high relative density was still achieved along with devitrification and embrittlement. While lower energy densities below ∼20 J/mm3 could retain a fully XRD amorphous structure, such samples had relative densities <99 %. When comparing the two powders, the coarse powder with four times lower oxygen content gave better glass forming ability, compression ductility up to 6 % plastic strain, and fracture toughness up to ∼38 MPa√m. These findings demonstrate that it is possible to tailor the structure and mechanical properties of BMGs by tuning the LPBF process parameters within a wide processing window.

Tetragonal phase-free crystallization of highly conductive nanoscale cubic garnet (Li6.1Al0.3La3Zr2O12) for all-solid-state lithium-metal batteries

The synthesis and processing of garnet-type conductors is usually done at temperatures above 1100 °C to reach the high Li-ion conducting cubic phase resulting in micron-sized particles and potential Li-loss, which are unfavorable for further processing and electrode-electrolyte assembly. Here, we tackle this problem and report a novel low-temperature aqueous synthesis route to stabilize the cubic phase of Li6.1Al0.3La3Zr2O12 (c-Al-LLZO) at a temperature as low as 600 °C, while obtaining nano-crystallites at around 100 - 200 nm. Moreover, a dual-reaction mechanism was proposed to describe the process of c-Al-LLZO crystallization. The as-synthesized nanoscale c-Al-LLZO particles facilitate the densification of the solid-state electrolyte (SSE) pellets with less endowed grain boundaries (exhibiting a high relative density of 97.8 %). The ionic conductivity reaches 0.42 mS cm−1 at 21 °C and the low activation energy (half of the published values) is 0.17 eV. The results presented here show that symmetric cells with Li metal exhibit excellent stability at the current density of 0.2 mA/cm2 and 0.5 mA/cm2, and an improved critical current density (CCD) of 2.16 mA/cm2. This work provides a feasible method of low-temperature crystallization of nanoscale cubic garnet SSEs with good performance for the fabrication of stable SSLBs.

Effect of Sr and Ta co-substitution on microstructure and ionic conductivity of cubic-Li0.5La0.5TiO3 electrolyte for applications in Li batteries

All-solid-state lithium batteries (ASSBs) have gained significant attention in recent years because of their potential to offer higher energy density and enhanced safety compared to conventional liquid-electrolyte-based lithium-ion batteries (LIBs). Lithium lanthanum titanate (LLTO) is a promising solid electrolyte for next-generation lithium batteries owing to its high ionic conductivity of approximately 10−3 S·cm−1 at room temperature (RT). The Sr and Ta co-doped Li0.5-□La0.5−xSrxTi1−xTaxO3 perovskites were synthesized by solid-state reaction. In this study, Sr2+ and Ta5+ with larger ionic radii, were used for co-substitution in the La3+ and Ti4+ sites, respectively, to increase the bottleneck size of the A-site and expand the average bond length of the B-site on the perovskite structure (ABO3), thereby increasing the Li+ ion mobility. The LLSrxTTaxO3 (0 ≤ x ≤ 0.12) pellets have high relative densities, and high grain conductivities, where the total conductivity of LLSr0.09TTa0.09O3 reached 4.12 × 10−5 S·cm−1. Compared with the pure specimen, the total conductivities of the doped specimens are approximately more than 2.7 times at RT. The assembled semi-solid LFP/10 wt% LLSr0.09TTa0.09O3/Li full battery has a 0.1 C specific discharge capacity of 156 mAh⋅g−1 and a 1 C capacity retention rate of 86% after 290 cycles at RT.

Plastic shaping of NiFe2O4‐based cermets using granular feedstock: microstructure and mechanical properties

AbstractCarbon‐free aluminum electrolysis is crucial for achieving the low‐carbon development and carbon neutrality in the future aluminum industry. NiFe2O4‐based cermet is the potential candidate of inert anode, benefiting from the satisfactory corrosion resistance and high‐temperature conductivity. Herein, complex‐shaped 25(Cu–20Ni)/(NiFe2O4–10NiO) cermets were fabricated via a plastic shaping method using the polyformaldehyde (POM)‐based granular feedstock. The feedstock showed uniform microstructure with evenly dispersed powders wrapped in polymers, which exhibited shear‐thinning behavior during molding. Roles of the feedstock with different powder loadings in the morphology and bending strength of the cermets were investigated. High‐precision gear parts exhibited no deformation, a high relative density over 98%. Investigation of different powder loadings revealed that parts prepared with a 56 vol% loading demonstrate the excellent performance, and possessed an impressive flexural strength of 178.4 MPa. This achievement provided a foundation for the future utilization of complex‐shaped inert anode material components in industrial applications.

Rapid Alloy Development Using Calphad Simulation and Powder Blends in Direct Energy Deposition

The ongoing commercialization of additive manufacturing (AM) has necessitated the need to tailor alloy chemistry as well as exploit AM process particularities such as freedom of design, print geometry and high cooling rates to meet functional application requirements. Alloys such as hot-work tool steels, including H11, are well suited for machining and tooling applications. In this work, the authors investigated and compared high-speed direct energy deposition with laser beam source (HS DED-LB/M) processability of a reference H11 alloy and its modified form (H11m). The modification of the alloy was intended to minimize the amount of retained austenite (RA) in as-built microstructure and reduce post-heat treatment steps. The investigative approach included Calphad simulation, rapid alloy blending (modified powder) and process parameter optimization to produce dense parts for microstructure characterization and mechanical properties testing. The results show that while H11 achieved a high relative density &gt; 99.85%, H11m still had cracks parallel to the building direction. The amount of RA was equally reduced from 4.08% in H11 to 1.23% in the H11m. H11 had a comparatively superior average microhardness (591 HV0.5) to H11m (561.5 HV0.5), which can be attributed to the more carbide presence. The martensitic strengthening effect between H11 and H11m can be described as similar.

Tuning hatch distance to optimize microstructure and mechanical properties of 2205 duplex stainless steel produced by laser powder bed fusion

Laser powder bed fusion (LPBF) of duplex stainless steel is a promising route to fabricate intricate parts with excellent mechanical properties. However, further understanding of build mechanisms is required to improve the process. This paper aims to better understand the influence of hatch distance on the densification behavior and figure out the correlation with microstructure and mechanical properties in LPBF of 2205 stainless steel. With the optimized laser power and scanning speed, the significant influence of hatch distance on the build quality is revealed. A hatch distance of 0.07 mm is selected for an even surface and dense part with a relative density of up to 99.13 %. The hatch distance has a crucial impact on the heat and mass transfer between tracks; hence, poor surface morphologies such as inter-track voids or swelling surfaces occur if an improper hatch distance is adopted. The optimal mechanical properties are also achieved. Specifically, the yield strength (0.2 YS), ultimate tensile strength (UTS), and elongation (EL) values are 896.8 MPa, 1035.13 MPa, and 15.34 %, respectively. The improvement in mechanical properties can be ascribed to the coordination between high dislocation density, fine grain size, high CSL boundaries and LAGBs, and high relative density with few pores. This work can help improve the build quality and expand the application horizon of duplex stainless steel for manufacturing intricate components.

ECOLOGY OF HORNBILL FOOD TREES AT BUKIT BARISAN SELATAN NATIONAL PARK

Hornbills play an important role in maintaining tree gene flow among fragmented populations in forests. But hornbill populations in Asia have been declining mainly due to loss of forest cover and poaching. The presence of hornbills in a forest is highly dependent on environmental factors such as the condition of food trees in their habitat. The purpose of this study was to determine the spatial distribution, dispersion patterns, density, and diversity of hornbill food trees at Sukaraja Atas Resort (SA) and Balik Bukit Resort (BB) of Bukit Barisan Selatan National Park (BBSNP). We investigated a total of 10 transect (50 survey plots) for both SA and BB by collecting data on all types of hornbill food trees with a minimum diameter of 10 cm at breast height (DBH). We recorded 64 hornbill food tree species with a total of 98 individuals, which have a clumped and uniform dispersion pattern. This study showed that Lauraceae dominated in both resorts with the highest relative density. The results of the diversity index show that 9 transect have moderate diversity whereas 1 transect has low diversity; there was no significant difference between SA and BB. It can be concluded that the existing food trees in SA and BB may support the hornbill populations.

A Mean-Strain Estimate for Plastic Particles Intended for Distinct-Particle Simulations at High Relative Density

A Mean-Strain Estimate for Plastic Particles Intended for Distinct-Particle Simulations at High Relative Density

Теплопроводность керамических композитов YAG:Nd + Mo, полученных методом электроимпульсного плазменного спекания

The microstructure and thermophysical properties (specific heat capacity, thermal conductivity coefficient, heat conductivity coefficient) of fine-grained ceramic composites based on yttrium-aluminum garnet Y2.5Nd0.5Al5O12 (YAG:Nd) with different molybdenum content (10, 20, 40 vol. %) are investigated. Submicron Y2.5Nd0.5Al5O12 powders are obtained by co-precipitation method. Powder compositions of YAG:Nd + Mo with the structure “YAG:Nd core – Mo shell” were obtained using wet chemistry techniques and precipitation of the metal phase from salt solutions. Ceramic composite samples were obtained by the Spark Plasma Sintering (SPS) method. The microstructure and phase composition of ceramics were investigated by electron microscopy and X-ray diffraction phase analysis. YAG:Nd + Mo composites have a high relative density (98.1 – 99 %) and a homogeneous fine-grained microstructure with a grain size of 2 – 3 μm. Increased thermal conductivity and heat conductivity of composites is provided with a content of at least 20 vol.% Mo. For composites with 20% and 40% Mo, the heat conductivity coefficient at 1100 °C reaches 7.0 and 8.8 W⋅m–1⋅K–1, respectively. Sintered composites YAG: Nd + Mo at room temperature and elevated temperatures (up to 1100 °C) have a high heat conductivity coefficient, exceeding the heat conductivity coefficient of uranium dioxide UO2. This makes it possible to use ceramics YAG:Nd+Mo as heat-resistant inert fuel matrices.

Influence of laser printing mode on thermal behaviors, forming characteristics, and microstructure evolutions of additive manufactured Ti6Al4V alloy

Ti6Al4V parts fabricated by laser powder bed fusion (LPBF) technology have been widely used in such fields as aerospace, automotive and medical implants. This study investigates the effect of laser scanning modes on thermal behaviors, forming characteristics, and microstructural evolutions of LPBF-fabricated Ti6Al4V parts. The numerical simulations on the temperature field provide a theoretical explanation of various surface morphologies, surface roughness values and relative densities of samples. The rotation between adjacent layers diminishes the large directional thermal stress generated by X scanning or Y scanning, the Ti6Al4V samples using XY scanning and Island scanning present smooth surface and higher relative density (> 99.0%). The observed staggered martensite within the columnar β grains is due to the epitaxial solidification across the deposited layers with 90° or 37° rotation. The martensite growth of LPBF-processed Ti6Al4V components using X scanning has a similar inclination along the building direction and presents anisotropic characteristics. These findings provide new inspirations for achieving high-performance titanium alloy components with specific microstructure by LPBF technique using a proper laser scanning mode.

Pottery glaze-derived sintering aids for the synthesis of NASICON electrolytes with high ionic conductivity and relative density

The glaze component is successfully utilized as a sintering aid to obtain a NASICON with high Na+ conductivity and relative density.

Effect of fibre orientation on the mechanical response of reinforced sand, detected with x-ray tomography

The mechanical behaviour of fibre-reinforced sands (FRS) has been thoroughly explored with a laboratory study, firstly investigating the influence of relevant parameters such as grading index, soil density, amount, diameter, and length of fibres then focusing on their orientation with respect to the principal stress directions. This aspect has been deeply investigated performing parallel tests on samples of pure sand and on samples with randomly and uniformly oriented fibres compacted at a similarly high relative density (Dr≈1). Direct and triaxial shear tests have been performed, the former enforcing deformation on a predetermined shear plane. The results show that reinforcement with oriented fibres provides a higher strength and ductility to the sand. The grain scale investigation of the materials’ response to direct shearing has been carried out performing X-ray tomography post-mortem (i.e., after the test). The evolution of porosity in several samples prepared with the same procedure and sheared under the same conditions has been studied freezing the material fabric with nanosilica grout injected at different displacement levels. On the contrary, X-ray tomography performed along with miniature triaxial tests (operando method) enabled the analysis of the spatial distribution of deviatoric strain too. In both cases, maps show the relevant role of fibres orientation with reference to the shear band. If adequately activated, fibres tension modifies the strain field in the samples, preventing the fragile rupture along a shear plane and transferring the stresses to the outer soil portions, in this way providing a more dilatant and ductile overall response of the reinforced material.

A low-temperature thermoelectric transport study of non-stoichiometric AgSbTe2.

In recent times, considerable attention has been given to examining the impact of micro/nanostructure on the thermoelectric characteristics of nonstoichiometric AgSbTe2. The present investigation employed direct melting of elements that produced p-type AgSbTe2 with spontaneous nanostructuring due to cation ordering. The product predominantly features an Ag-deficient Ag0.927Sb1.07Te2.005 phase with monoclinic Ag2Te nanoprecipitates and exhibits a degenerate semiconductor-like behavior with an energy band gap of 0.15 eV. A Seebeck coefficient of 251 μV K-1 and a power factor of 741 μW m-1 K-2 at near ambient temperature are attained with this composition. The variable range hopping (VRH) and linear magnetoresistance (LMR) confirmed that the low-temperature transport followed a VRH between the localized states. The composition also exhibited glass like thermal conductivity of 0.2 W m-1 K-1 arising from phonon scattering at all-scale hierarchical structures that led to a high ZT of 1.1 at room temperature. The direct melted ingots show a high relative density of ∼97%, Vickers hardness Hv of ∼108.5 kgf mm-2, and excellent thermal stability, making them an attractive choice for TEGs.

Enhanced quality factor (∼336,800 GHz) of MgTiO3 ceramic by Hf substitution for Ti-site

Mg(Ti1–xHfx)O3 (0 ≤ x ≤ 0.1) microwave dielectric ceramics were synthesized by solid-state reaction method. The effects of Hf substitution for the Ti-site on the phase composition, structure, and microwave dielectric properties of MgTiO3 ceramic were systematically investigated. The study demonstrated that Hf substitution significantly improved the quality factor of MgTiO3 ceramic. A single phase was confirmed at x = 0.002 and 0.005 by XRD and SEM, while secondary phases were observed at x ≥ 0.02. The Rietveld refinement of XRD data implied that the distortion of [Ti(Hf)O6] octahedron started with alleviation and then gradually deteriorated with an increase in Hf content. Raman spectra displayed that the frequencies of the vibrational modes were high when there was low distortion in [Ti(Hf)O6] octahedron, manifesting that the low distortion weakened the effect of non-harmonic vibration. The quality factor of the samples with x ≤ 0.05 was far higher than that of undoped MgTiO3, which may be related to low distortion in [Ti(Hf)O6] octahedron and high relative density. Notably, the excellent microwave dielectric properties of Q × f ∼336,829 GHz, εr ∼17.2 and τf ∼ -49.7 ppm/°C were achieved for the Mg(Ti0.995Hf0.005)O3 ceramic. The greatly improved quality factor of MgTiO3-based microwave ceramics through Hf substitution makes it a suitable candidate material for ceramic filters.

Cf/SiC Ceramic Matrix Composites with Extraordinary Thermomechanical Properties up to 2000 °C.

The thermomechanical properties of carbon fiber reinforced silicon carbide ceramic matrix composites (Cf/SiC CMCs) were studied up to 2000 °C using high-temperature in situ flexural testing in argon. The CMC specimens were fabricated using an ultrahigh concentration (66 vol%) aqueous slurry containing nano-sized silicon carbide powder. The SiC powder compacts were obtained by drying the slurry and were densified using the precursor impregnation and pyrolysis (PIP) method with field assisted sintering technology/spark plasma sintering (FAST/SPS). The high relative density of the SiC green body (77.6%) enabled densification within 2.5 days using four PIP cycles. In contrast, conventional PIP processes take over 7 days. The in situ flexural strength of the Cf/SiC CMC was 434 MPa at 1750 °C, which was 84% higher than the room temperature value. The value further increased to 542 MPa at 2000 °C. Possible mechanisms to explain the excellent strength of the CMC at elevated temperatures are discussed.

Investigation on the Attainment of High-Density 316L Stainless Steel with Selective Laser Sintering.

Due to the low density of the green part produced by selective laser sintering (SLS), previous reports mainly improve the sample's density through the infiltration of low-melting metals or using isostatic pressing technology. In this study, the feasibility of preparing high-density 316L stainless steel using 316L and epoxy resin E-12 as raw materials for SLS combined with debinding and sintering was investigated. The results indicated that in an argon atmosphere, high carbon and oxygen contents, along with the uneven distribution of oxygen, led to the formation of impurity phases such as metal oxides, including Cr2O3 and FeO, preventing the effective densification of the sintered samples. Hydrogen-sintered samples can achieve a high relative density exceeding 98% without losing their original design shape. This can be attributed to hydrogen's strong reducibility (effectively reducing the carbon and oxygen contents in the samples, improving their distribution uniformity, and eliminating impurity phases) and hydrogen's higher thermal conductivity (about 10 times that of argon, reducing temperature gradients in the sintered samples and promoting better sintering). The microstructure of the hydrogen-sintered samples consisted of equiaxed austenite and ferrite phases. The samples exhibited the highest values of tensile strength, yield strength, and elongation at 1440 °C, reaching 513.5 MPa, 187.4 MPa, and 76.1%, respectively.