Ball-milled Powders Research Articles

Deformation behavior of harmonic structure designed CoCrFeMnNi HE alloys

This paper presents the deformation behavior of CoCrFeMnNi high-entropy alloy (HEA) produced from plastically undeformed and deformed powders. The investigation commenced with the preparation of ball-milled HEA powder at 90ks and 180ks, with a ball-to-powder ratio of 2:1, to induce severe plastic deformation on the outer layer of the HEA powder. Subsequently, the plastically undeformed and deformed HEA powders were successfully consolidated in a spark plasma sintering (SPS) furnace. The SEM observations revealed that the sintered plastically undeformed HEA powder exhibited conventional homogeneous microstructures (Homo), while sintered deformed HEA powders exhibited a regulated bimodal grain distribution known as harmonic structure (HS). The mechanical properties of the materials were characterized by performing tensile tests at room temperature (RT) and a low temperature of 193 K. The HS HEA exhibited an increase in proof strength of 16%–40%, while the ultimate tensile strength (UTS) increased by 8%–20% compared to the Homo HEA. Moreover, the strain hardening rate (SHR) curve indicates that both Homo and HS HEA exhibited oscillatory behavior at low temperature. However, Homo HEA exhibited more pronounced oscillation than HS HEA. The current results indicate that oscillatory behavior in the SHR curve is indicative of twin deformation. At low temperatures, the high rate of twinning deformation in Homo HEA was attributed to its higher ductility, while a good combination of high strength and high ductility produced by HS material was found to be influenced by HS design in addition to twinning deformation.

Fabrication of TiN-doped Ti nanocomposites with high strength and ductility by plasma-assisted ball milling and laser powder bed fusion

An efficient method to fabricate titanium nitride (TiN)-doped titanium (Ti) nanocomposites through a combination of plasma milling, plasma spheroidization, and laser powder bed fusion (LPBF) was developed to obtain Ti-based materials with high strength and ductility from commercially pure titanium (CP-Ti). Nitrogen plasma milling and plasma spheroidization were used to fabricate Ti-TiN nanocomposites, which were mixed with CP-Ti powder at a 1:9 ratio and printed by LPBF forming. The resulting materials possessed a dual-scale morphology with both coarse lath-like and fine acicular-like grains. The Ti-TiN nanocomposites possessed higher hardness and tensile strength and lower ductility than those of the control sample without TiN. The mechanical properties of the LPBF-printed Ti-TiN nanocomposites were improved compared with those of LPBF-printed CP-Ti because of the TiN particles and resulting dual-scale structure. Nitrogen plasma milling provides a simple route to fabricate TiN nanophase-reinforced Ti-based nanocomposites suitable for LPBF printing.Graphical

Synthesis of Mo-Cu nanocomposite powder by hydrogen reduction of copper nitrate coated MoO3 powder mixture

The fabrication of Mo-based nanocomposite powder with homogeneous dispersion of Cu was investigated. The fine MoO3 powders were prepared by high energy ball milling, and Cu particles on the ball-milled powder surfaces were formed by calcination of a precursor solution copper nitrate. In the powder mixture calcined at 300 °C, MoO3 and CuO appeared in the form of aggregates with fine particles. Microstructural analysis showed that the oxide powders were changed to Mo-Cu nanocomposite powders with an average particle size of about 150 nm and had microstructural homogeneity by hydrogen reduction at 800 °C for 1 h. These results are help to optimize the synthesis process of homogeneous Mo-Co nanocomposite powders.

Large coercivity and enhanced magnetization in La-substituted Sm6Mn23 alloys

The magnetic properties of Sm6Mn23-based alloys are still not fully understood for their high complexity in magnetic and crystallographic structures. This work presents studies of the structure and magnetic properties of Sm6Mn23 and Sm5LaMn23 alloys. The results show that both the binary and La-substituted ternary alloys crystallize in a cubic Th6Mn23 type structure (Fm-3m) with trace amount of Mn impurities. The lattice parameter of Sm5LaMn23 is slightly larger than that of Sm6Mn23. The Curie temperature of Sm5LaMn23 is ∼403 K, which is lower than that of Sm6Mn23. A field-dependent magnetic transition was observed in Sm5LaMn23, which shows a decreasing temperature at which Sm5LaMn23 exhibiting maximal magnetization with increasing field, indicating a suppression of the antiferromagnetic coupling of the rare earth and Mn moments under applied field. Large coercivities up to 0.74 T and 1.2 T are observed in Sm5LaMn23 bulk alloys and powders, respectively. The saturate magnetization, the remanent magnetization, and the coercivity of Sm5LaMn23 at 5 K are much higher than that of Sm6Mn23. The ball-milled Sm5LaMn23 powders exhibit significantly enhanced coercivity and magnetization. The refinement of the grain size during ball-milling results in the enhanced coercivity. The magnetic purification of the powders and possible local ferromagnetic configuration of the surface Mn atoms may result in the enhanced magnetization.

Evidence of multiferroic behavior in sintered BaTiO3 obtained from high-energy ball-milled powders

Multiferroic BaTiO3 exhibiting ferroelectric and ferromagnetic behavior was synthesized via the high-energy ball milling of pure BaTiO3 (BTO) powders for durations ranging from 15 to 60 min, followed by pressing and sintering at 1200°C X-ray diffraction patterns of all synthesized samples predominantly revealed a BTO phase with a tetragonal structure and a secondary Ba12Fe28Ti15O84 (BFTO) phase. The BFTO phase was formed after milling for more than 30 min because of chemical interactions between the BTO powder and milling media. Vibrating sample magnetometry confirmed the ferromagnetic nature of the sintered pellets. The specific magnetization increased with increasing milling duration, reaching a maximum value of 1.15 emu/g after 60 min of milling. This increase can be attributed to the distortion of the crystal structure and presence of a secondary phase, as confirmed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. Additionally, electrical characterization revealed the dielectric nature of the materials, with relative permittivity ranging from 500 to 1800, maximum spontaneous polarization from 9.77 to 11.31 μC/cm2, coercive field from 3.86 to 11.12 kV/cm, and AC conductivity from 1 x 10−6 to 1 x 10−3 S/cm. The method described in this study is a simple and cost-effective approach to produce multiferroic materials with ferroelectric and relaxor ferroelectric behavior at room temperature, broadening their potential for technological applications.

Microstructural, Electrochemical, and Hot Corrosion Analysis of CoCrFeCuTi High Entropy Alloy Reinforced Titanium Matrix Composites synthesized by Microwave Sintering

CoCrFeCuTi High Entropy Alloy (HEA) is reinforced in Ti6Al6V2Sn alloy through microwave sintering-assisted powder metallurgy and its corrosion behaviour is investigated under different conditions. The ball-milled CoCrFeCuTi HEA powder exhibits 17 μm average particle size of irregular fragments with a single-phase BCC structure and is added as reinforcement in Ti alloy at 3, 6, 9, and 12 wt%. As more reinforcement is added, the α-Ti decreases and β-Ti increases which enhances the interfacial bonding. The pinning effects from reinforcements inhibit grain growth contributing to improved properties including higher relative density with less porosity. The 12 wt% composite showed remarkable microhardness of 734 HV which is increased by 43.8% over Ti alloy. The 12 wt% composite also achieved finer grains (0.345 μm) due to uniform internal heat generation from the process. Corrosion behaviour is assessed through electrochemical corrosion and hot corrosion analysis, with 12 wt% composite demonstrating 59.5% better corrosion resistance compared to Ti alloy. The induced corrosion products, formation of passivation films, and their mechanism are examined by morphological analysis.

Compaction behavior of freeze-dried and spray-dried trypsin/lactose particulate systems

Development of oral solid dosage forms containing biologics has attracted intense interests recently due to the high patient convenience and the commercial potential of related products. The aim of this study was to understand how the difference in the particle properties prepared using two different drying principles, i.e. freeze-drying and spray-drying, may influence the compaction behavior of particulate protein systems. Here, trypsin was used as a model protein drug and lactose as a filler. The raw freeze-dried (FD) powder composed mostly of trypsin and lactose was dissolved in Milli-Q water and processed by spray-drying to produce spray-dried (SD) powder. Meanwhile, the raw FD powder was micronized by a ball mill into fine ball-milled (BM) powder with a comparable particle size to that of SD powder. Next, the FD, BM and SD powders were characterized with regard to morphology, residual moisture content (RMC), solid form, and surface chemistry using scanning electron microscope (SEM), thermogravimetric analysis (TGA), X-ray powder diffraction (XRPD), and X-ray photoelectron spectroscopy (XPS), respectively. Subsequently, a compaction simulator was employed to prepare tablets within the compaction pressure range of 25 to 400 MPa. The results showed that FD and BM powders could be compressed into tablets within the investigated compaction pressure range. In contrast, tablets compacted from SD powder displayed capping/lamination tendency under high compaction pressures and thus had poor tabletability. XPS analyses revealed that there were more surface enrichments of trypsin in the SD powder compared to that of FD powder. It implies that there would be more hydrophobic inter-particulate trypsin-trypsin interactions and less hydrophilic lactose-lactose interactions during the compression of SD powder compared to the compaction of FD powder. The weak hydrophobic inter-particulate trypsin-trypsin interactions may not be maintained during the decompression phase especially when compacted at high compaction pressure ranges, resulting in capping/lamination of the SD tablets. This study demonstrates that the two drying principles, i.e. freeze-drying and spray-drying, can result in different particle properties of biologics, which can in turn influence the tabletability of the resulting solid materials.

A FeCrAl-Al2O3 Composite Produced Via Laser Powder Bed Fusion of a Mixed Powder for Porous Catalyst Scaffolds

Abstract This study proposes a novel approach for synthesizing and etching bicontinuous FeCrAl-Al2O3 composites as a means for replacing FeCrAl foams as catalyst scaffolds in biodriven alcohol reactors for jet-fuel production. Conventional FeCrAl foams suffer from poor availability and consequent high costs. New additive manufacturing techniques provide an opportunity to produce tailored foams at reasonable times and at acceptable costs. This research aimed to generate a porous FeCrAl structure by etching a bicontinuous FeCrAl-Al2O3 composite produced by laser powder bed fusion of amalgamated FeCrAl and Al2O3 powders. The composite powder for laser powder bed fusion is created by ball-milling FeCrAl and Al2O3 powders. This research focuses on achieving a bi-continuous FeCrAl-Al2O3 structure, essential for the selective removal of the ceramic phase. The influence of laser processing parameters on the microstructure was examined across a range of laser powers (60–120 W) and scan speeds (100–400 mm/s), showing that higher powers and speeds produce finer metal struts. A bi-continuous microstructure was consistently obtained, marking a key achievement. The Al2O3 removal process involved a two-step etching method using hydrochloric and phosphoric acids, tested across various etching times. The alumina phase was reduced from 36 vol% to 17 vol% (corresponding to an increase in porosity from 24 vol% to 43 vol%), showing the potential for use as a porous catalyst scaffold. This research demonstrates the potential for using additive manufacturing to produce porous FeCrAl structures capable of replacing hard-to-source FeCrAl foams.

X-Ray Crystallographic Analysis of Pr Modified BaTiO3 Ceramics with a Theoretical Perspective for Potential Applications in Microelectronics

By examining the diffraction data, the microstructure of the ball-milled synthesized powder sample ([Formula: see text][Formula: see text]TiO3) was characterized. Through the application of Rietveld’s powder structure refinement approach to analyze X-ray powder diffraction data of ball-milled powder mixes, structural and microstructural alterations in terms of lattice defects have been assessed in the formation of single-phase praseodymium-modified BaTiO3. Bond lengths, bond angles, and generated locations of the [Formula: see text]Pr0[Formula: see text]TiO3 ceramic have been discussed about its generated structure. X-ray diffraction with respect to the first sharp diffraction peak (FSDP) is used to study the nanostructure of void species. General equations were utilized to determine various FSDP characteristics such as interlayer separation, correlation length, nanovoid diameter and scattering vector magnitude. Although the literature reports on many properties of Pr-modified barium titanate ceramic, this sample’s quantitative analysis and nanovoid determination are presented for the first time.

Time-Dependent Multi-Particle Model Describing the Hydrogen Absorption of Nanocrystalline Magnesium Powders: A Case Study

Classical kinetic models describing the hydrogen absorption of nanocrystalline metallic hydrides generally do not involve any parameter related to the change in the crystallite size during the hydrogenation at constant temperature. In the present investigation, ball-milled nanocrystalline Mg powders exhibiting lognormal crystallite size distribution have been subjected to hydrogen absorption in a Sievert-type apparatus. Partially absorbed states were achieved by interrupting the hydrogenation cycle at different hydrogen content, i.e., when 15%, 50%, and 90% of Mg powder transformed to MgH2. The evolution of the characteristic size of the nucleating MgH2 phase was determined from X-ray diffraction analysis. Considering the crystallite size distribution of the as-milled powder agglomerate as well as the growth during the isothermal hydrogenation process, a time-dependent multi-particle reaction function ∝CV¯t;R(t) was developed. It was shown unambiguously for this case study that the measured hydrogen absorption curve of the ball-milled Mg powder shows the best correlation with this model when it is compared to classical kinetic functions or the previously developed multi-particle reaction function excluding the change in the average crystallite size during hydrogenation.

Manufacturing Oxide Dispersion Strengthened (ODS) steel plate via cold spray and friction stir processing

Oxide dispersion strengthened (ODS) steels, traditionally fabricated by ball milling and conventional powder metallurgy techniques to achieve bulk form, followed by intricate rolling and thermal treatment steps to achieve plate or sheet form. Here, we present a novel processing route that combines cold spray (CS) with friction stir processing (FSP) to manufacture ODS steel plate directly from gas atomization reaction synthesis (GARS)-prepared powder, thus no rolling steps involved. Microstructural and mechanical characterizations were performed to assess the quality and properties of the resulting ODS steel plate. Our findings demonstrate that the slightly porous CS deposited layer was fully consolidated after FSP, yielding a fully dense ODS steel plate that exhibited a favorable tradeoff between strength and ductility upon extraction from the substrate. Furthermore, through microstructural analysis, we revealed the presence of an appreciable density (∼1022/m3) of nano-sized oxide particles, with the majority being smaller than 5 nm via the combined CS + FSP fabrication route. This work serves as a first proof-of-concept demonstration of the manufacturing approach described herein, offering a possible alternative route for producing ODS steel plates.

Effect of Ti content on microstructure and mechanical properties of TaMoNbCrTix refractory high-entropy alloy

Refractory high entropy alloys (RHEAs) hold great promise for applications requiring high-temperature resistance. In this study, TaMoNbCrTix (x = 0, 0.25. 0.5, 0.75, 1) RHEAs were fabricated through mechanical alloying (MA) and spark plasma sintering (SPS). The effect of Ti content on the microstructure and mechanical properties of TaMoNbCrTix RHEAs was investigated. The results revealed that the alloys consisted of a body-centred cubic (BCC) matrix and Laves phase, with the addition of Ti promoting the formation of the Ti(O, N) phase. By employing severe deformation of the ball-milled powder, short sintering time, and the inhibition of precipitated phases on grain growth, the resulting RHEAs exhibited ultrafine grains measuring less than 1 μm. As the Ti content increased, the volume fraction of the Laves phase decreased, transitioning from a reticulated to a dispersed distribution. This shift had a positive influence on the ductility of the alloys. Among the studied compositions, TaMoNbCrTi0.75 displayed desirable comprehensive mechanical properties with yield strength, compressive strength, and fracture strain of 2696 MPa, 3098 MPa, and 16.8%, respectively. Notably, the ductility exhibited by TaMoNbCrTi0.75 at room temperature surpassed that of most Cr-containing RHEAs.

Influence of powder ball milling pretreatment on microstructure and properties of Mo-W-Cu refractory functional alloys sintered in a normal-pressure hydrogen atmosphere

In this work, the effect of powder ball milling pretreatment on the microstructure and properties of the Mo-30W-20Cu (mass fraction) refractory functional alloys sintered in normal-pressure H2 is investigated systematically. The results indicate that a moderate milling can obviously refine the particle size of the Mo-30W-20Cu composite powder, largely contributing to the sintering densification and thermo-physical property improvement. In contrast, an excess milling instead causes reaggregation of plastic Cu particles, negatively influencing the following compact densification and the property improvement. The composition analysis shows that there is a strong compositional inheritance correlation between the pretreated powders and the corresponding bulk alloys. Besides, the experimental and the calculated results of the thermal and electrical conductivities of the sintered alloys are compared, and they show a similar trend with milling time varying. This work can provide valuable theoretical and technological insights for preparation of high-performance Mo-W-Cu refractory functional alloys.

Waste to Resource: Surface Modification of Electric Arc Furnace Flue Dust by Ball Milling and In Situ Carbonization

In this article, instead of synthesizing the electrode active material using expensive precursors that lead to high carbon emissions to the atmosphere during fabrication, an alternative engineering approach is presented for the utilization of the electric arc furnace flue dust, which is an industrial waste, as anode material in lithium-ion batteries. In this scope, firstly ball milling of the flue dust with citric acid is applied and then in situ carbonization conditions are optimized by pyrolyzing the mixture at different temperatures (600 °C and 750 °C) and times (4 h and 6 h). Every sample delivers capacities greater than graphite. Structural, morphological, and chemical characterization results demonstrate that the designed method not only promotes the formation of a nanometer-thick carbon layer formation over the particles but also induces partial phase transformation in the structure. The best performance is achieved when citric acid is used as the carbon source and the ball-milled powder is treated at 600 °C for 4 h in nitrogen (C6004): It delivers 714 mAh g−1 capacity under a current load of 50 mA g−1 after 100 cycles. This research is expected to set an example for the utilization of different industrial wastes in high value-added applications, such as energy storage.Graphical

Effect of Cr3C2 distribution on the wear and corrosion properties of HVOF-sprayed WC–12Co/Cr3C2–25NiCr composite coatings

In this study, experimental ball-milling mixed feedstock powder (BMP) and spray-drying feedstock powder (SDP) were prepared, and the WC–12Co/Cr3C2–25NiCr coatings were sprayed with high-velocity oxygen fuel (HVOF). The microstructures, phase compositions, as well as wear and corrosion resistance of the two coatings were explored. The results indicated that SDP at a 250 °C inlet temperature and 2 wt% binder had a uniform elemental distribution, excellent fluidity, and apparent density. The SDP coating was also more uniform and denser than the SMP coating. In addition, an amorphous phase formed in the SDP coating during the HVOF process. The SDP coating exhibited a uniform microstructure, better wear property, and wear rate of 5.5 × 10−14 m3/(N∙m), which is 29% lower than that of the BMP coating. Furthermore, the SDP coating showed superior corrosion resistance in a 36 wt% HCl solution, with a corrosion current of about 2.26 × 10−3 A∙cm−2 and corrosion rate of 26.57 mm/a, which is 81.8% lower than that of the BMP coating. The molecular dynamics simulation indicated that the uniform distribution of Cr3C2–25NiCr substantially reduced the adsorption energy of HCl for WC–12Co.

Synthesis of rGO-reinforced MgAl2O4 spinel composites by solid-state powder route mechanism: A comparative analysis between non-reinforced and rGO-reinforced spinel composites

Reduced Graphene Oxide (rGO)-reinforced MgAl2O4 spinel composite was successfully synthesized by a solid-state powder route mechanism via high-energy planetary ball milling of corresponding metal oxide precursors followed by a high-temperature single-stage sintering process. The effect of rGO on the homogeneity, phase development, morphology, chemical composition, rate of formation of spinel, and cation anti-site formation of the composites was methodically investigated. For comparison, a stoichiometric non-reinforced MgAl2O4 spinel was also synthesized. The addition of 0.2 wt% and 0.4 wt% of rGO as reinforcement increased the homogeneity of the ball-milled composite powder, with Polydispersity Index (PDI) values of 0.19 and 0.15 respectively, as compared to 0.24 obtained in non-reinforced spinel composite. The X-ray diffraction pattern and IR spectrum of 1650 °C sintered composites confirmed the formation of highly crystalline phases with spinel structure. The microstructural analysis revealed that the addition of rGO led to a reduction in porosity and improved the process of sintering. Calorimetric studies showed that spinelization started to occur at 858 °C and 880 °C for 0.2 wt% and 0.4 wt% rGO-reinforced composites respectively, which was faster than non-reinforced composite. 27Al solid-sate nuclear magnetic resonance (SS-NMR) analysis depicted that ceramic composite reinforced with rGO exhibited lesser inversion parameter of 0.09 (for 0.2 wt% rGO) and 0.055 (for 0.4 wt% rGO), as compared to 0.145 obtained in non-reinforced composite, indicating lesser cation anti-sites formation in rGO-reinforced spinel composite.

Microstructure and performance optimization of laser cladding nano-TiC modified nickel-based alloy coatings

In this study, different alloy powders containing nano-sized TiC were prepared using a combination of mixed ball milling adsorption, electroless Ni-P-TiC, and Ni-B-TiC plating techniques. The effects of different nano-TiC addition methods on the microstructure, wear resistance, and corrosion resistance of laser-coated nickel-based self-fusing alloy coatings were comprehensively studied. The effects of the nano-TiC method on the microstructure, wear resistance, and corrosion resistance of laser-coated nickel-based self-fusing alloy coatings were comprehensively studied. The results show that agglomerated TiC particles appeared in the coatings prepared with ball-milled powder. In contrast, the coatings produced by introducing nano-sized TiC through the chemical plating methods exhibited a uniform distribution of the TiC phase. The coatings prepared with Ni-B-TiC plating powder showed a bimodal microstructure and most of the TiC particles are distributed at grain boundaries, which hinders grain growth and refines the microstructure of the coating. The corrosion resistance of the Ni2 coating prepared with ball milling adsorbed nano TiC powder shows the best corrosion resistance. The wear resistance of the Ni4 coating prepared with the Ni-B-TiC plating powder was significantly better than that of the other samples. This study provides an effective way to improve the wear or corrosion resistance of laser cladding nickel-based self-fluxable alloy coatings.

The effect of Ge substitution on phase transformation and magnetic properties of MnBi alloys

The Mn55Bi45-xGex intermetallic compound with x ≤ 4 was prepared and compared by annealed ribbons and powder metallurgy. Substituting Ge in the MnBi alloy significantly alters the phase transformation temperatures, enhances the coercivity (Hc), and improves the squareness. As the Ge concentration increased from 0 at.% to 4 at.%, both the crystalline size of low-temperature phase MnBi in annealed ribbons and ball-milled powders demonstrated a gradual decrease, while lattice strain exhibited an upward trend. The Hc of Mn55Bi41Ge4 powder reaches 14.1 kOe, which is 33 % higher than that of pure MnBi powder, making MnBi-Ge an ideal candidate magnet for the next generation of rare-earth-free magnets.

Steam oxidation properties of graphene reinforced bioinspired laminated CoCrFeNiMn high-entropy alloy matrix composites at 1000 ℃

Laminated CoCrFeNiMn high-entropy alloy (HEA) matrix composites reinforced with 1.0 wt% graphene nanoplatelets (GNPs) were fabricated by mechanical ball milling and flake powder metallurgy, and were isothermal oxidized at 1000 ℃ for 100 h. Vacuum hot-pressure sintering (VHPS) shows a distinct nacre structure with the microstructure composed of FCC matrix phase, Cr23C6, CrMn1.5O4 precipitated phases, numerous dislocations and twins. High-temperature oxidation tests showed that the composites had mass gains at 12 h intervals from 12 to 100 h respectively. The oxidation kinetic curve changes from a linear pattern in the early stages to an exponential pattern in the later stages, which demonstrates better long-term oxidation resistance. The anisotropy of the laminated structure results in excellent resistance to high-temperature steam oxidation in the vertical lamellar direction. Observation of the cross-section reveals that although Cr2O3 (inner layer) is present, (Mn, Cr)3O4 and Mn3O4 are the dominant oxides (outer layer). Elemental depletion zones for Mn and Cr exist in the region of the matrix near the oxide scales. The results show that the oxidation resistance of the laminated GNPs/CoCrFeNiMn composites is mainly influenced by the diffusion of Mn and Cr elements, the microstructure of the laminations and the internal oxidation.

Metal Scrap to Hydrogen: Manufacture of Hydroreactive Solid Shapes via Combination of Ball Milling, Cold Pressing, and Spark Plasma Sintering.

Two sorts of tablets were manufactured from ball-milled powder (aluminum scrap and copper) by cold pressing and spark plasma sintering. Their microstructure, phase, and elemental compositions were investigated via scanning electron microscopy, X-ray diffraction analysis, and energy-dispersive X-ray spectroscopy. New phases, Al2Cu and MgCuAl2, were detected in the samples. Their microstructure was formed by welded scrap particles, the intermetallides, and Cu-rich regions located majorly along 'interparticle boundaries' and, to a lesser extent, within small, micro- and nanosized 'intraparticle spots'. The tablets were sealed with adhesive, so only the top surface was exposed to the environment, and tested in a chlorine aqueous solution for hydrogen generation performance. For both sample sorts, hydrogen yields of nearly 100% were achieved. The sintered tablets reacted faster than the cold-pressed ones: at 60, 70, and 80 °C, their entire 'conversion into hydrogen' took ~80, 40, and 30 min. vs. ~220, 100, and 70 min. The experimental kinetic curves were fitted with a contracting geometry equation, and those for the sintered samples were approximated with higher precision. The key effect of the additive was to enhance hydrogen evolution through the galvanic corrosion of Al in the regions adjacent to the intermetallic inclusions and Cu-rich spots.