Pre-alloyed Powder Research Articles

An additively manufactured γ-based high Nb-TiAl composite via coherent interface regulation

Novel γ-based TiAl alloys are a promising alternative to conventional dual-phase TiAl alloys, which suffer from microstructural degradation and solid-state phase transformations at high temperatures. However, monolithic intermetallic γ phases exhibit poor plasticity, and they are incompatible with conventional manufacturing techniques. In this study, a microstructural modification was used to enable the preparation of a single-phase matrix from an Nb-rich TiAl metal matrix composite using additive manufacturing (AM) techniques. Micro/nano-precipitates of Ti5Si3 and Ti2AlN were produced by adding Si3N4 precursors to the pre-alloy powder, which reacted with the γ-TiAl matrix during the AM process. Thus, strong interfacial cohesion was achieved. The Ti5Si3 and Ti2AlN precipitates refined the grains in the metal and Ti5Si3 strengthened the grain boundaries. The enhanced interfacial cohesion and unique distribution of precipitates suppressed intergranular cracks during AM and increased the plasticity of the alloy.

Multiple intermetallic compounds reinforced Ti–48Al alloy with simple composition and high strength

The short communication presents a synergistical reinforced Ti–48Al alloy with multiple Ti–Al intermetallic compounds which was prepared with irregular pre-alloyed powders by vacuum sintering at low temperature (1250°C). With simple composition, this alloy has tensile and yield strength of 593 ± 8 MPa and 435 ± 5 MPa at room temperature, and more than 510 MPa and 490 MPa at 700°C, reached the level of Ti–Al alloys with complex composition.

A new strategy for metal additive manufacturing using an economical water-atomized iron powder for laser powder bed fusion

We develop a pre-alloyed water-atomized (WA) iron powder for laser powder bed fusion (LPBF)-based 3D printers; such a powder has never been used for 3D printing. The powder features low levels of nano-sized Cu-Ni-Mo; these alloying elements are placed into the concavities of the iron powder. When these powders were used for LPBF printing, the processing window for the volumetric energy density ranged from 93 to 130 J/mm3. However, careful control of laser power (150 – 225 W) and scan speed (500 – 900 mm/s) was essential. In terms of production, a maximum relative density of 99.67% was achieved upon application of an energy density of 108 J/mm3 (175 W, 700 mm/s). An average hardness of 217.1 ± 4.7 HV was obtained, exhibiting stable standard deviations and confirming excellent mechanical homogeneity. Energy-dispersive X-ray spectroscopy mapping revealed excellent chemical homogeneity; this translated to good mechanical homogeneity because of the uniform mixing of the nano-sized alloying elements. The printed tensile bars were stable and of a relatively high aspect ratio. Tensile strength measurements revealed that samples prepared using the partially pre-alloyed iron powder were better than those fabricated from simple raw WA iron powder; the former samples exhibited an ultimate tensile strength (UTS) of 460.91 MPa with elongation of 6.98% and the latter a UTS of 197.15 MPa with elongation of 0.45%. Therefore, the pre-alloyed WA iron powder developed in this study can successfully be used in LPBF and presents a more cost-effective alternative to traditional gas atomized iron powders.

Laser-based powder bed fusion of pre-alloyed oxide dispersion strengthened steel containing yttrium

In this study, the pre-alloyed powder Fe-22Cr-5.1Al-0.5Ti-0.26Y (wt%) was prepared by nitrogen atomization and characterized with the aid of focused ion beam (FIB) and transmission electron microscopy (TEM). The oxide dispersion strengthened (ODS) bulk material was successfully fabricated using laser-based powder bed fusion (PBF-LB). Micro-scale Y-Al-O complex oxides and nanoscale Y 2 O 3 @TiN core-shell structures were found in the as-built material. The importance of the presence of residual oxygen in the atomization system and the building chamber for the formation of dual-scale secondary phases was revealed. In addition, the formation mechanism of the dual-scale secondary phases was elucidated by investigating the phase and composition of the as-built ODS steel. Columnar crystals with {001}< 100 > cubic alignments grew epitaxially from the bottom of the molten pool during the PBF-LB process, forming a weak cubic texture in the as-built material. This cubic texture led to anisotropic tensile properties of the as-built material, where the room-temperature ultimate tensile strength in the XY-45° direction was higher than that in the building direction (Z). Our work provides a feasible scheme to shorten the preparation process of ODS alloys, which is usually carried out using complicated means. • The Y-containing pre-alloyed powder was prepared by nitrogen atomization. • Primary precipitates in the powder were characterized by FIB and TEM. • Residual oxygen participated in the alloying reaction in the molten metal. • Formation mechanisms of oxides and cubic texture were revealed.

Characteristics of β-type Ti-41Nb alloy produced by laser powder bed fusion: Microstructure, mechanical properties and in vitro biocompatibility

A β-type Ti-41Nb alloy with high relative density has been successfully fabricated by laser powder bed fusion (l-PBF) using pre-alloyed powders for potential implant application. The homogeneous microstructure can be achieved in l-PBF fabricated (l-PBFed) Ti-41Nb alloy but slight composition segregation was detected along molten pool boundaries. The l-PBFed alloy was dominated by typical epitaxial columnar grains with strong 〈001〉 grain orientation along building direction (BD), and cellular structure was distinguished within the columnar grains. The main reasons for this microstructure can be attributed to effective thermal gradient and epitaxial growth. l-PBFed alloy exhibited higher mechanical strength compared with cold rolling plus annealing (CRA) alloy due to the finer grains, dislocations accumulation and different TRIP behaviors, accompanied by good ductility. It also exhibited much lower thermal conductivity and better hydrophilic feature than those of CP-Ti. Besides, the l-PBFed alloy exhibited slightly better cell spread and cell proliferation rates compared with CP-Ti. Moreover, l-PBFed alloy presented better alkaline phosphatase (ALP) activities and extracellular matrix (ECM) mineralization, which suggests that the l-PBFed alloy can stimulate the osteogenic differentiation of rat bone mesenchymal stem cells. The Ti-41Nb alloy, fabricated by l-PBF, reveals a good combination of mechanical properties, physicochemical properties and biocompatibility, exhibiting the great potential as the dental implant.

Laser powder bed fusion of an Al-Cr-Fe-Ni high-entropy alloy produced by blending of prealloyed and elemental powder: Process parameters, microstructures and mechanical properties

High-entropy alloys in the Al-(Co)-Cr-Fe-Ni system have been designed along several pathways to obtain tailored microstructures with remarkable mechanical properties, such as high strength and ductility. Additive manufacturing techniques, such as laser powder bed fusion, have been utilized and aim towards further optimization of their mechanical properties. However, processing challenges exist for these promising alloys, mainly due to their crack susceptibility as recently shown in the Co-free Al-Cr-Fe-Ni alloy. In this study, gas atomized prealloyed powder of a baseline Al-Cr-Fe-Ni high-entropy alloy was mixed with Fe and Ni elemental fine powder particles, to produce a powder blend with a modified composition. It was aimed to improve the alloy processability via designing the solidification path by reducing the Al content. The synthesized novel alloy composition was processed by laser powder bed fusion and crack-free material with a metastable, near single-phase face-centered cubic microstructure was obtained. Process parameters for minimum porosity were identified and net-shape tensile specimens were produced. Heat treatment led to a refined dual-phase microstructure consisting of face-centered cubic and body-centered cubic phases with promising mechanical properties, such as high tensile strength, reasonable elongation and notable strain hardening.

Microstructural Characteristics of Ti‐Based Composites with Various Ceramic Reinforcements Manufactured via Hydrogen‐Assisted Blended Elemental Powder Metallurgy

The manufacturing of in situ reinforced titanium matrix composites by the sintering of titanium hydride and ceramic powder blends is an attractive and cost‐efficient process. Herein, a novel two‐stage (double‐compaction/double‐sintering) hydrogen‐assisted powder approach is suggested to produce uniform highly dense Ti‐based composites reinforced with TiB, TiC, and dual TiC + TiB phase particles. In this approach, the hydrogenation and milling of presintered products enable the initial porous materials to transform into hydrogenated prealloyed (PA) powders of controlled sizes, and a second press‐and‐sinter process further converts the PA powders into nearly dense composite microstructures with evenly distributed fine reinforcements. The adverse effect of the raw reinforcing powder size on microstructure uniformity, porosity, and mechanical characteristics of the presintered in situ composites becomes negligible in final sintering stage. The reduction of the porosity and enhancement of the hardness indicate that the hydrogen‐assisted double‐compaction and double‐sintering blended elemental powder metallurgy (BEPM) + PA approach enables the low‐cost fabrication of Ti‐based composites with suitable mechanical characteristics.

The Study on Resolution Factors of LPBF Technology for Manufacturing Superelastic NiTi Endodontic Files.

Laser Powder Bed Fusion (LPBF) technology is a new trend in manufacturing complex geometric structures from metals. This technology allows producing topologically optimized parts for aerospace, medical and industrial sectors where a high performance-to-weight ratio is required. Commonly the feature size for such applications is higher than 300–400 microns. However, for several possible applications of LPBF technology, for example, microfluidic devices, stents for coronary vessels, porous filters, dentistry, etc., a significant increase in the resolution is required. This work is aimed to study the resolution factors of LPBF technology for the manufacturing of superelastic instruments for endodontic treatment, namely Self-Adjusting Files (SAF). Samples of thin walls with different incline angles and SAF samples were manufactured from Nickel-Titanium pre-alloyed powder with a 15–45 μm fraction. The printing procedure was done using an LPBF set-up equipped with a conventional ytterbium fiber laser with a nominal laser spot diameter of 55 microns. The results reveal physical, apparatus, and software factors limiting the resolution of the LPBF technology. Additionally, XRD and DSC tests were done to study the effect of single track based scanning mode manufacturing on the phase composition and phase transformation temperatures. Found combination of optimal process parameters including laser power of 100 W, scanning speed of 850 mm/s, and layer thickness of 20 μm was suitable for manufacturing SAF files with the required resolution. The results will be helpful for the production of NiTi micro objects based on periodic structures both by the LPBF and μLPBF methods.

Validation of the Powder Metallurgical Processing of Duplex Stainless Steels through Hot Isostatic Pressing with Integrated Heat Treatment.

Duplex stainless steels exhibit an excellent combination of corrosion resistance and strength and are increasingly being manufactured through powder metallurgy (PM) to produce large, near-net-shaped components, such as those used for offshore applications. Hot isostatic pressing (HIP) is often used for PM production, in which pre-alloyed powders are compacted under high pressures and temperatures. Recent developments in HIP technology enable fast cooling as part of the process cycle, reaching cooling rates comparable to oil quenching or even faster. This enables the integrated solution annealing of duplex stainless steels directly after compaction. In contrast to the conventional HIP route, which requires another separate solution annealing step after compaction, the integrated heat treatment within the HIP process saves both energy and time. Due to this potential gain, HIP compaction at a high pressure of 170 MPa and 1150 °C with integrated solution annealing for the production of duplex stainless steels was investigated in this work. Firstly, the focus was to investigate the influence of pressure on the phase stability during the integrated solution annealing of the steel X2CrNiMoN22-5-3. Secondly, the steel X2CrNiMoCuWN25-7-4, which is highly susceptible to sigma phase embrittlement, was used to investigate whether the cooling rates used in the HIP are sufficient for preventing the formation of this brittle microstructural constituent. This work shows that the high pressure used during the solution heat treatment stabilizes the austenite. In addition, it was verified that the cooling rates during quenching stage in HIP are sufficient for preventing the formation of the sigma phase in the X2CrNiMoCuWN25-7-4 duplex stainless steel.

Effect of powder size segregation on the mechanical properties of hot isostatic pressing Inconel 718 alloys

Pre-alloyed powder of Inconel 718 alloy was prepared by electrode induction melting gas atomization (EIGA) and powder metallurgy (PM) Inconel 718 alloys were made through hot isostatic pressing (HIPing) route. The change in volume of large size parts (special-shaped cylindrical capsule) has a much lower effect on the alloy than the powder size. The vibration of the powder filling process over a long time causes the particle size segregation phenomenon that the proportion of coarse particle powders in top part increases, and the proportion of finer particle powders in middle and bottom part increases. This phenomenon has little effect on tensile strength of PM Inconel 718 alloys at room temperature and 650 °C, but has a significant effect on elongation, room temperature impact properties, and stress rupture life at 650 °C/725 MPa. Compared to finer particle powders, the plastic deformation of coarse particle powders is small and a large number of under-deformed powder particles are retained, forming prior particle boundaries (PPBs) and reducing the bonding strength between powder particles. In order to avoid particle size segregation, optimized process parameters and reasonable particle size should be used.

Extrusion-based additive manufacturing of Mg-Zn alloy scaffolds

Porous biodegradable Mg and its alloys are considered to have a great potential to serve as ideal bone substitutes. The recent progress in additive manufacturing (AM) has prompted its application to fabricate Mg scaffolds with geometrically ordered porous structures. Extrusion-based AM, followed by debinding and sintering, has been recently demonstrated as a powerful approach to fabricating such Mg scaffolds, which can avoid some crucial problems encountered when applying powder bed fusion AM techniques. However, such pure Mg scaffolds exhibit a too high rate of in vitro biodegradation. In the present research, alloying through a pre-alloyed Mg-Zn powder was ultilized to enhance the corrosion resistance and mechanical properties of AM geometrically ordered Mg-Zn scaffolds simultaneously. The in vitro biodegradation behavior, mechanical properties, and electrochemical response of the fabricated Mg-Zn scaffolds were evaluated. Moreover, the response of preosteoblasts to these scaffolds was systematically evaluated and compared with their response to pure Mg scaffolds. The Mg-Zn scaffolds with a porosity of 50.3% and strut density of 93.1% were composed of the Mg matrix and MgZn 2 second phase particles. The in vitro biodegradation rate of the Mg-Zn scaffolds decreased by 81% at day 1, as compared to pure Mg scaffolds. Over 28 days of static immersion in modified simulated body fluid, the corrosion rate of the Mg-Zn scaffolds decreased from 2.3 ± 0.9 mm/y to 0.7 ± 0.1 mm/y. The yield strength and Young's modulus of the Mg-Zn scaffolds were about 3 times as high as those of pure Mg scaffolds and remained within the range of those of trabecular bone throughout the biodegradation tests. Indirect culture of MC3T3-E1 preosteoblasts in Mg-Zn extracts indicated favorable cytocompatibility. In direct cell culture, some cells could spread and form filopodia on the surface of the Mg-Zn scaffolds. Overall, this study demonstrates the great potential of the extrusion-based AM Mg-Zn scaffolds to be further developed as biodegradable bone-substituting biomaterials.

In-house synthesis of CoCrFeNi ingots using an electric furnace

• Ingots of Multi-Principal Element Alloys is mostly obtained by casting using special equipment. • Melting and natural cooling of prealloyed powders in an electric furnace is a valid alternative. • A necessary requisite for adopting this static synthesis method is lack of liquid phase separation. • The proof-of-concept material was an equimolar CoCrFeNi alloy. • Microsegregation due to solute partitioning was mitigated through annealing. Bulk Multi-Principal Element Alloys (MPEAs) are generally synthesized by casting, a process needing specific equipment. Here, a standard laboratory electric furnace was used to synthesize bulk CoCrFeNi by melting of prealloyed powders followed by natural cooling. The use of prealloyed powders guaranteed atomic-level mixing. In accordance with the literature, the resulting ingot had a face-centered cubic structure. A typical dendritic-interdendritic microstructure was obtained which was explained by partitioning during solidification and grain boundary wetting phenomenon. Post-annealing treatment improved chemical homogeneity without crystallographic phase change. This work shows the feasibility of melt-aided synthesis of CoCrFeNi HEA under static conditions using a conventional laboratory furnace.

Application of Unconstrained Cobalt and Aluminium Metal Powders in the Alloying of Carbon Steel in Submerged Arc Welding: Thermodynamic Analysis of Gas Reactions

The application of cobalt and aluminium powders in unconstrained format, not as metal powder in tubular wire nor as pre-alloyed powder, is used in this work to simplify weld metal alloying. The objective of this study is to demonstrate the application of unconstrained cobalt and aluminium powders in Submerged Arc Welding SAW to alloy the weld metal and to control the weld metal oxygen content. Aluminium powder is used to control the oxygen potential at the weld pool-slag interface in order to prevent oxidation of cobalt. The results presented here show that with the addition of Aluminium powder, 70% yield of Cobalt was achieved from the cobalt powder to the weld metal. The carbon steel base-plate material and weld wire materials combination were alloyed to 5.3% Co and 4.2% Al, whilst controlling the weld metal total oxygen content to 230 ppm. Thermodynamic analysis is applied to investigate the possible chemical interaction reactions between Co and Al compounds, as well as the role of the reactions on Co yield to the weld pool. The application of unconstrained metal powders ensures productivity gains in the overall SAW process because the time consuming and expensive manufacturing of alloyed wire and alloyed powder are eliminated.

The influence of micro-nano Ti2AlC on the hot deformation behavior of TiAl alloys

To strengthen TiAl alloys, micro-nano Ti2AlC precipitates were fabricated in situ by spark plasma sintering using Ti–48Al–2Nb–2Cr pre-alloyed powder and multilayer graphene oxide. The effect of micro-nano Ti2AlC precipitation on the hot deformation behavior of Ti–48Al–2Nb–2Cr alloy was systematically studied at 1100, 1150, and 1200 °C under strain rates of 0.01, 0.1, and 1 s−1. The fully lamellar structure was transformed to a nearly lamellar structure when the graphene content was increased. In addition, the lamellar colony size significantly decreased and the number of Ti2AlC particles increased with increasing graphene content. The hot deformation results show that the flow stress of the Ti2AlC–TiAl composites first increased and then decreased with increasing graphene content, reaching the maximum with the addition of 0.3 wt% graphene. Micro-nano Ti2AlC particles hindered dislocation slip, leading to a strengthening effect. However, Ti2AlC particles promoted dynamic recrystallization through grain refinement and dislocation pile-up, resulting in a softening effect. The strengthening and softening effects of the Ti2AlC–TiAl composites depend on the Ti2AlC particle content.

Composition inhomogeneity reduces cracking susceptibility in additively manufactured AlCoCrFeNi2.1 eutectic high-entropy alloy produced by laser powder bed fusion

Pre-alloyed and blended powders are frequently used feedstock options for additive manufacturing; however, nanoscale compositional inhomogeneities induced by blended powders are often ignored. This composition inhomogeneity is more pronounced in eutectic high-entropy alloys (HEAs) with small solidification ranges and sluggish diffusion effects. In this study, AlCoCrFeNi 2.1 eutectic HEAs were prepared by laser powder bed fusion (LPBF) using both pre-alloyed and blended powders. The alloy built using the pre-alloyed powder (PA) exhibited cellular structures that consisted of ordered body-centered cubic (B2) cells decorated with face-centered cubic (FCC) networks. The composition inhomogeneity in the alloy built using blended powders (BP) led to lamellar structures consisting of alternate FCC and B2 lamellas. The orientation relationships between FCC and B2 in both PA and BP were determined as {110} B2 //{100} FCC , < 001 > B2 //< 011 > FCC . The fine cellular structures in PA resulted in high ultimate strength (1400 MPa) but poor ductility. Solid-state cracking and delay cracking were observed in PA. The straight and extended FCC lamella in BP provided preferential channels and long distances for dislocation slippages, which combined high strength (1200 MPa) and ductility (10%). The improved deformation ability of BP enabled a strain-tolerant microstructure and eliminated the solid-state and delay cracking in as-built LPBF AlCoCrFeNi 2.1 alloys. • AlCoCrFeNi2.1 HEAs were additive manufactured by pre-alloyed and blended powders, respectively. • Cellular structures consisting of B2 cells and FCC networks were associated with cracks. • Lamellar B2/FCC structures resulted in an excellent combination of strength and ductility. • Composition inhomogeneity produced by blended powders eliminated cracks.

Mechanical anisotropy of laser powder bed fusion fabricated Ti-41Nb alloy using pre-alloyed powder: Roles played by grain morphology and crystallographic orientation

This work investigated the influence of the grain morphology and crystallographic orientation on the mechanical anisotropy of a laser powder bed fusion produced (L-PBFed) Ti-41 Nb alloy using pre-alloyed alloy for dental implants. The microstructure of L-PBFed Ti-41Nb alloy consists of columnar grains of a high aspect ratio with a strong< 001 > preferred orientation along the building direction (BD). To evaluate the mechanical anisotropy of L-PBFed Ti-41 Nb alloy, the external loading was compressed either perpendicular or parallel to BD (i.e., horizontal and vertical samples, respectively). Compression results show that the compressive yield strength (CYS) of horizontal samples is significantly higher than that of vertical samples. At the early stage of deformation, obvious {332}< 113 > mechanical twins are preferentially detected in the nearly< 001 > orientated grains along the compression axis. The dominant reasons for the lower CYS of vertical samples can be attributed to the easier activation of {332}〈113〉 mechanical twins in the typical columnar grains with strong< 001 > crystallographic orientation. It is suggested that the anisotropy of the L-PBFed alloy can be utilized through simple position control such as adjustment of the BD and reasonable structural design.

Microstructure and mechanical properties of Co-containing Ti-48Al alloys prepared from irregular pre-alloyed powder

Poor sinterability of powder metallurgy TiAl-based alloy is an important factor that restricts its industrial production. In this paper, we improve the sinterability of Ti-48Al alloy by adding Co element. In such case, the relative density of Ti–48Al based alloy sintered at 1250 ℃ increases from 82.6% to 96% with an increase of Co content from 0 to 1.5 at%. The densification improvement is caused by liquid TiAl2Co phase, which is formed at 1230 ℃. Then, uniform and fine near-γ microstructure is obtained, and the grain size increases with the increasing of Co content. More than 70% of grains in the Ti-48Al-0.5Co alloy are smaller than 2 µm. Overall, Ti-48Al-0.5Co alloy has better comprehensive performance, with compressive strength of 2533 MPa, yield strength of 683 MPa and fracture strain of 29.5%.

Investigations on laser powder bed fusion of tungsten heavy alloys

Laser powder bed fusion (L-PBF) offers significant potentialities for the design of complex part geometries. Due to the specific combination of properties, tungsten heavy alloys are used for special applications such as X-ray and γ-radiation shielding, balancing weights, collimators and molds. For optimum performance, complex geometries can be required in those applications. L-PBF of tungsten heavy alloys such as W-Ni-Fe is challenging due to the high thermal conductivity, high viscosity of the liquid phase, the high melting point and sensitivity to thermal cracking. The effect of L-PBF processing parameters on the material microstructure is therefore studied for different W-Ni-Fe powders, applying substrate preheating temperatures up to 800 °C. Furthermore, the impact of thermal post-treatment is investigated, leading to a microstructure close to conventionally sintered material. Crack-free samples can be generated from all powders, but residual and heterogeneously distributed pores are still detected. It is shown that evaporation of NiFe binder matrix during L-PBF is significantly lower for pre-alloyed powders than for mixed powders.

Microstructure evolution and elevated temperature wear performance of in-situ laser-synthesized Ti-25Al-17Nb coating on Ti-6Al-4V

A ternary Ti-25Al-17 Nb coating (89.5 vol. % O phase and 4.3 vol. % α2 phase) was fabricated from the pre-alloyed powder by in-situ laser synthesis. The powder was laser scanned to form α2 phase at high temperature and subsequently precipitated primary Ti2AlNb phase (O phase) in an acicular structure; while the secondary fine acicular O phase was squeezed due to the expansion of α2 phase with induced some edge dislocations and mixed dislocations. The dense and hard Al2O3 film gradually replaced the loose and porous TiO2 oxide film as an oxygen diffusion barrier, thereby reducing the possibility of brittle oxide formation and significantly increasing the wear resistance and oxidation resistance, results in an excellent wear resistance at 800 ℃.

Searching New Solutions for NiTi Sensors through Indirect Additive Manufacturing.

Shape Memory Alloys (SMAs) can play an essential role in developing novel active sensors for self-healing, including aeronautical systems. However, the NiTi SMAs available in the market are almost limited to wires, small sheets, and coatings. This restriction is mainly due to the difficulty in processing NiTi through conventional processes. Thus, the objective of this study is to evaluate the potential of one of the most promising routes for NiTi additive manufacturing—material extrusion (MEX). Optimizing the different steps during processing is mandatory to avoid brittle secondary phases formation, such as Ni3Ti. The prime NiTi powder is prealloyed, but it also contains NiTi2 and Ni as secondary phases. The present study highlights the role of Ni and NiTi2, with the later having a melting temperature (Tm = 984 °C) lower than the NiTi sintering temperature, thus allowing a welcome liquid phase sintering (LPS). Nevertheless, the reaction of the liquid phase with the Ni phase could contribute to the formation of brittle intermetallic compounds, particularly around NiTi and NiTi2 phases, affecting the final structural properties of the 3D object. The addition of TiH2 to the virgin prealloyed NiTi powder was also studied and revealed the non-formation of Ni3Ti for a specific composition. The balancing addition of extra Ni revealed priority in the Ni3Ti appearance, emphasizing the role of Ni. Feedstocks extruded (filaments) and green strands (layers), before and after debinding & sintering, were used as homothetic of 3D objects for evaluation of defects (microtomography), microstructures, and mechanical properties. The composition of prealloyed powder with 5 wt.% TiH2 addition after sintering showed a homogeneous matrix with the NiTi2 second phase uniformly dispersed.