Solution Treated And Aged Research Articles

Defects, microstructure and associated mechanical properties of Inconel 718 fabricated by selective electron beam melting

Comprehensive characterizations and evaluations were conducted on the relationship between process parameters and density in the Inconel 718 (IN718) alloy fabricated by selective electron beam melting (SEBM). Additionally, the microstructure and anisotropy of tensile properties were evaluated in both the as-built state and after solution treatment and aging (STA). During different stages of energy density, the primary contributors to the porosity rate transitioned from the lack of fusion (LF) pores to the inclusion of spherical and shrinkage pores, resulting in a maximum relative density of 98.95 %. The as-built parts displayed notable parallel texture to the building direction, and a significant tensile anisotropy supported by the Taylor factor. The matrix of these parts consisted of δ, γ', γ″, and carbonitrides, with a considerable presence of δ precipitation leading to a reduction in γ″ content and lower strength. After heat treatment, the δ dissolved, and γ″ precipitated extensively, while the carbonitrides and texture were retained. However, unique tensile results contradicting the predictions made by computational modeling were observed, we propose a new insight attributed to the presence of shrinkage pores along the build direction and use finite element analysis to support this view.

Microstructure Control for Enhancing the Combination of Strength and Elongation in Ti-6Al-4V through Heat Treatment

For the application of Ti-6Al-4V alloys in urban air mobility, safety is very important, so achieving excellent strength and toughness is essential to prevent fractures. Regarding toughness, which is a combination of strength and ductility, it is necessary to derive the optimal heat treatment conditions for this combination of Ti-6Al-4V alloy and further understand its microstructure and fracture characteristics. For this purpose, this study investigated the microstructure in terms of grain size, plate thickness, and element distribution, as well as mechanical properties, including phase hardness and tensile properties, of Ti-6Al-4V alloy subjected to solution treatment and aging (STA) heat treatment under various aging conditions. As a result, this study suggests that solution treatment followed by aging at 630 °C for 480 min can achieve approximately 26% higher toughness than the just-solution treatment process. This is because there is little difference in hardness between the equiaxed α and basketweave structures, and β plates, which contain an excessive V between α plates, function like fibers and delay fracture.

Effect of Zn content on the formability and aging precipitation of Al–Zn–Mg–Cu–Nb alloys prepared by LPBF

In this work, the effect of Zn content on the formability and aging precipitation of Al–Zn–Mg–Cu–Nb alloys prepared by laser powder bed fusion (LPBF) were investigated via experiments and in-depth characterization. Results show that the increase in Zn content narrows the LPBF processing window, owing to the significant evaporation of Zn element during LPBF. The increase of Zn content not only accelerates the aging kinetics of Al–Zn–Mg–Cu–Nb alloys, but also increases the number density of nanoprecipitates and reduces the PFZ width, resulting in an enhancement in the peak microhardness. The microstructure evolution and aging behavior of alloys during direct aging (DA) and traditional solution treatment and aging (STA) were compared. DA can maintain fine equiaxed grains, while a bimodal grain structure with coarse and fine grains can be obtained after STA. The peak microhardness and the number density of nanoprecipitates in alloys treated with STA is higher than that of alloys treated with DA, which indicates that the traditional STA heat treatment is still applicable to Al–Zn–Mg–Cu–Nb alloys fabricated by LPBF.

Effect of Heat Treatment on the Microstructure and Mechanical Properties of Rotary Friction Welded Dissimilar IN718 to SS304L Alloys

The present study investigated the effect of heat treatment (pre- and post-weld) on the microstructure and mechanical properties of an SS304L/IN718 dissimilar rotary friction welded alloy. Optical and scanning electron micrographs of the dissimilar rotary friction welded SS304L/IN718 joints in solution-treated (ST), solution-treated and aged (STA), and post-weld heat treatment (PWHT) conditions revealed defect-free welds. Furthermore, various zones were observed across the weld region, namely the fully deformed zone (FDZ), thermomechanical affected zone (TMAZ), heat affected zone (HAZ), and base material (BM). Among the SS304L/IN718 dissimilar friction welds with different heat treatment conditions (prior ST and STA, PWHT), the PWHTed dissimilar welds exhibited excellent mechanical properties, which could be attributed to the formation of the strengthening precipitates γ′ and γ″ during double aging in PWHT. In contrast, the mechanical properties were found to be the poorest in the STA condition, possibly due to the dissolution of the strengthening precipitates γ′ and γ″ during friction welding. It was observed that the SS304L/IN718 dissimilar friction welds in the ST and STA conditions failed in the HAZ of the SS304L side, away from the weld interface, indicating that the weld region was stronger than the weakest base metal (SS304L) in the various joints.

Additive manufacturing-based repair of IN718 superalloy and high-cycle fatigue assessment of the joint

Room-temperature high-cycle fatigue (HCF) of IN718 repaired joint via laser direct energy deposition (DED) were studied with the fatigue axis perpendicular to the joint interface. Solution treated and aged (STA) were compared with directly aged (DA) conditions. The wrought IN718 substrate showed equiaxed grains with a size of ~90 μm and a high fraction of annealing twins, whereas the DED deposit revealed a mixture of equiaxed and columnar grains with an average size of ~20 μm. There was little difference between the STA and DA conditions in the grain length-scale. Micro-hardness results highlighted the need for the heat treatment as it can remove the heat-affected zone and hardness dip, creating a uniform hardness profile across the joint. Although the monolithic DED deposit had a similar tensile strength to the wrought substrate, the DED joint exhibited an overall decreased HCF performance, regardless of the heat treatment conditions. When the fatigue stress was low, the STA condition had a better HCF performance than the DA, however, the opposite trend appeared for the high stress, resulting in a cross-over point on the stress-life S - N plot. Interrupted fatigue tests, combined with microscopy and fractography, revealed that the fatigue failure occurred in the substrate for the DED joint in the DA condition, whilst in the deposit zone for the STA condition due to the distribution and fracture of the Laves and δ phases. Grain boundary cracking in the substrate near the substrate-to-deposit interface can occur in both cases, probably due to the Nb-rich liquid films. • High-cycle fatigue of AM IN718 repaired joints with loading perpendicular to the interface • Post heat treatment can effectively eliminate the heat affected zone • Directly aged joint outperforms the solution treated and aged joint under high fatigue stress • Whereas the solution treated one performs better under low fatigue stress • Such an unexpected phenomenon is reconciled using single-specimen interrupted tests

Dislocations mobility in superalloy-steel hybrid components produced using wire arc additive manufacturing

A hybrid component consisting of Inconel 718 superalloy (IN718) and mild/low structural steel (grade S275) was fabricated using the wire + arc additive manufacturing (WAAM) technology to evaluate the feasibility, texture, and the corresponding characteristics. S275 is considered as a mild/low alloy steel that is compatible with IN718 and can serve as a mechanically under-matched substrate for WAAM deposition with potential use in the petrochemical industry. Characterization of the interfacial hybrid part was conducted through Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), and Electron Backscatter Diffraction (EBSD) in three different states of as-built (AB), solution-treated (ST), and aged (STA) conditions. EDS elemental mapping confirmed the presence of Laves closer to the interface even after 1-hour solutionizing at 1080 °C. Solution-treatment resulted in eliminating microsegregation (mainly Nb) and considerable Laves dissolution, along with a significant decrease of the hardness in both WAAM-deposited IN718 and the substrate. The bulk texture of WAAM-deposited IN718 was measured by neutron diffraction in all three states of AB, ST, and STA, showing a strong 〈002〉 texture parallel to the building direction (BD). Elastic-field mathematical models were used to interpret the role of heat treatment in perfect-, and partial dislocations’ mobility and Peierls-Nabarro stress by considering the neutron diffraction and nanohardness data collected across the interface. Limiting aspects associated with dissimilar joining of IN718 and S275 alongside post-processing heat-treatments were pointed. Recommendations were made to facilitate possible additive repair of IN718 hybrid parts for various industrial applications.

Influence of post-heat treatment on the microstructure and mechanical properties of Al-Cu-Mg-Zr alloy manufactured by selective laser melting

The properties of modified conventional wrought aluminum alloys cannot be significantly enhanced by normal post-heat treatment in that the fine-grained strengthening, arising from high cooling rate in SLM, is underutilized. In this work, compared with the normal T6 heat treatment, a novel simple direct aging regime was proposed to maintain the grain-boundary strengthening and to utilize the precipitation strengthening of secondary Al3Zr. It was found that a heterogeneous grain structure, which consisted of ultrafine equiaxed (∼0.82 μm) and columnar (∼1.80 μm) grains at the bottom and top of molten pool, respectively, was formed in the SLM processed sample. After direct aging (DA), the ultrafine grains were maintained and a mass of spherical coherent L12-Al3Zr particles with a mean radius of approximately 1.15 nm was precipitated. In contrast, after solution treatment and aging (STA), a significant grain coarsening occurred in the equiaxed grain region. Meanwhile, the coarsening L12-Al3Zr particles, nano-sized S′ phases and GPB zones were detected in the STA sample. This subsequently induced that the yield strength of the DA sample (∼435 MPa) was higher than that of the STA sample (∼402 MPa) owing to the grain boundary strengthening and precipitation strengthening. Both the STA and DA samples exhibited a higher strength than that of the other SLMed Al-Cu-Mg series alloys; this was comparable to that of the wrought AA2024-T6 alloy (∼393 MPa). Both the STA and DA samples exhibited a higher strength than that of the other SLMed Al-Cu-Mg series alloys; this was comparable to that of the wrought AA2024-T6 alloy (∼393 MPa).

Synchronous involvement of topology and microstructure to design additively manufactured lattice structures

This article presents a methodical approach to optimize microstructure (e.g., the crystallographic texture) and topology (e.g., unit cell and struts) concurrently to improve the mechanical properties of additively manufactured metallic lattice structures (AMLS), i.e., yield strength and plastic flow stress. Full-field elasto-viscoplastic Fast Fourier Transform (EVP-FFT) crystal plasticity (CP) simulations are employed to determine the optimal microstructure. The CP model parameters were calibrated to measured macroscopic stress–strain response and microstructural data for polycrystalline samples of additively manufactured (AM) Inconel 718 with solution treated and aged (STA) microstructure. Since the crystallographic orientation of the constituent single-crystal grains with respect to the loading direction has a significant impact on the mechanical behavior of the material, stress projection factor analysis was used to determine four candidate textures to explore in for a given unit cell topology. Full-field crystal plasticity simulations were used to determine macroscale yield surface parameters for each of the considered textures, thereby enabling macroscale lattice unit cell simulations that account for the underlying microstructure. The calibrated microstructure-dependent yield surfaces are used to investigate the effect of different microstructures on the mechanical response of different LS topologies with the same relative density. The results show that in a texture with <111> crystallographic direction, parallel to the loading direction, the tensile and compressive yield strength are 20% and 58% larger, respectively compared to the AM STA IN718 texture. Furthermore, when this texture is used in conjunction with the Rhoctan topology, the results demonstrate 50% improvement in both the yield strength and modulus of elasticity relative to previously optimized AMLS designs that did not directly account for microstructure. This simultaneous consideration of microstructure and topology during optimization, thus, significantly enhances the structural integrity of the AMLS.

The Application of Differential Scanning Calorimetry to Investigate Precipitation Behavior in Nickel-Base Superalloys Under Continuous Cooling and Heating Conditions

A suite of experimental tools and fast-acting, numerical-simulation techniques was used to quantify the precipitation behavior of three nickel-base superalloys: IN-100, LSHR, and 718. Experimental methods comprised differential scanning calorimetry (DSC) to establish the specific heat as a function of temperature and selected direct-resistance heating trials (using a Gleeble® machine) to obtain samples for microstructural analysis. For the DSC experiments, each alloy was cooled at a prescribed constant rate (between 5 and 20 K/min) after an initial soak/equilibration in the high-temperature, single-phase (supersolvus) temperature regime. On-heating DSC trials beginning at ambient temperature were also performed on alloy 718 in three different starting conditions: super-δ-solvus solution treated and water quenched (denoted as ST), solution treated and aged (STA), and solution treated and overaged (STOA). DSC results, revealing the thermal signatures associated with the kinetics of precipitation of γ′ (IN-100, LSHR) or γ′ and γ″ (718), were interpreted using a previously-developed fast-acting routine that treats concurrent nucleation, growth, coarsening, and dissolution. For these simulations, special attention was paid to various thermo-kinetic input parameters including equilibrium solvus-approach curves, bulk free energies of transformation, matrix-precipitate interface energies, and effective diffusivities. For the γ-γ′ superalloys (IN-100 and LSHR), estimates of precipitate volume fraction as a function of temperature from the specific-heat data revealed semi-quantitative agreement with simulation predictions. For the γ-γ′-γ″ superalloy (718), simulation predictions of precipitate volume fractions were converted to specific heat as a function of temperature and showed semi-quantitative agreement with the direct measurements.

An Investigation of corrosion of friction welded and post-weld heat-treated AA6061/SiC/graphite hybrid composites

The aluminium-based hybrid metal matrix composites have noteworthy applications in sub-sea installations, structures of deep-sea crawlers, submarine parts, engine cylinders, drum brakes etc., as they possess high strength, corrosion resistance, chemical, and dimensional stability. In this investigation, the pitting corrosion behaviour of friction welded and post-weld heat-treated AA6061/SiC/graphite hybrid composites were analysed. The corrosion rates of AW (as welded), ST (Solution treated), STA (Solution treated and Aged), and AA (Artificially Aged) weld joints were experimentally determined. The corrosion behaviour has been discussed in light of microstructure. The experimental results revealed that the STA joints exhibited better corrosion resistance characteristics as compared to AW, AA, and ST joints. The corrosion rate was high for AW joints, followed by AA and ST joints, respectively. Taking into account the corrosion rates of AW and STA joints, the STA joints have a corrosion rate 34.6% lesser than that of AW joints. A comparison of AA and ST with STA joints reveals that the rate of corrosion for STA joints was 31.1% lesser than that of AA joints and 28.8% lesser than that of ST joints. A lower corrosion rate was observed for STA joints as compared to AA, AW, and ST joints.

Effect of Cooling Rate on Microstructure and Hardness during Solution Treatment and Aging Process of Ti-6Al-4V Alloy for Aerospace Components

The microstructure and hardness of Ti-6Al-4V alloys were evaluated before and after aging to investigate the effect of the cooling rate at the solution treatment stage of the solution treatment and aging (STA) process for aerospace components. The cooling rate distribution across a Ti-6Al-4V alloy sample representing practical STA process of an aerospace fan disk component was estimated using finite element analysis. The Ti-6Al-4V alloy specimens were solution-treated with the obtained cooling rates, and aged. Experimental WQ of the Ti-6Al-4V alloy specimen in the solution treatment facilitated the retention of the primary α phase, while the β phase was transformed to α′. Controlled cooling at slower rates compared to WQ led to the formation of coarser globular α and the transformation of β to α+β lamellae. Subsequent aging of the specimens led to the observation of α+β lamellae in all specimens regardless of the cooling conditions, where the average thickness of the plates in lamellae was higher at slower cooling rates. The specimens exhibited higher hardness values when cooled more quickly at the solution treatment, which was attributed to the formation of thinner α plates and/or a higher α′ fraction. The hardness value of all specimens increased further after aging, regardless of the cooling conditions, due to precipitation of Ti3Al in the α phase and/or fine α plates from the α′ phase.

Orthogonal machining of Heat Treated Ti-10-2-3: FE and Experimental

ABSTRACT Nowadays, finite element analysis is the best suitable approach to reduce the need for several experiments. This paper is based on the FE modeling and model validation via the experimental value of turning operation in 2D on heat-treated Titanium alloy (Ti-10-2-3 is also named as Ti-10 V-2Fe-3Al). Turning operation is treated as an orthogonal cutting process and this operation is simulated using Abaqus® explicit 6.14 software, with the help of Johnson–Cook material constructive model with boundary conditions. FE simulation results were validated with experimentally obtained forces and cutting temperatures during turning operation on different cutting thickness. Simulation and the experiment were conducted on the three different heat-treated conditions of the Ti-10-2-3 like Solution Treatment and Aging (STA), Annealed and Solution Treated and Overaged (STOA). The model validation showed that the average errors in the prediction and the experimental values are cutting force 4%, feed force 3% and temperature 11%. In this model, the simulated value of the average feed force was slightly less than the experimental value due to the consideration of actual friction between tool–chip interfaces on the rake face.

IN100 Ni-based superalloy fabricated by micro-laser aided additive manufacturing: Correlation of the microstructure and fracture mechanism

IN100 Ni-based superalloy fabricated by micro-laser aided additive manufacturing (micro-LAAM) was investigated in this study. After solution treatment and aging (STA) of the micro-LAAMed IN100 alloy, hierarchical γ′ phases were recognized and characterized, which contributed significantly to the high ultimate tensile strength (~1050 MPa) and acceptable ductility (5%) at 25 °C and 600 °C. The tensile fractured surfaces of the as-built and STAed IN100 were characterized by dimples and dimples/cleavages, respectively. The high cycle vibration fatigue (HCVF) behavior was preliminarily studied through simulating the service conditions of some cantilever structures in automobile and aerospace industries. Compared with the cast IN100, the micro-LAAMed IN100 superalloys (as-built or STAed) both exhibited inferior HCVF lives. The HCVF behavior was discussed and correlated with the microstructure characteristics, such as the preferred growth direction of the grains in micro-LAAMed IN100 and the massive interfaces existing in the final obtained material. In the present study, the hierarchical γ′ phases were beneficial to the static tensile property, whereas detrimental to the HCVF behavior of the final obtained IN100 to some extent.

Strengthening of Ti-6Al-7Nb alloy by high-pressure torsion processing

A Ti-6Al-7Nb alloy with three different initial microstructures was processed by high-pressure torsion (HPT) and the resultant microstructure and mechanical properties of the alloy after HPT processing were investigated. The microstructure of the as-received alloy was an equiaxed (α+β) microstructure. The rods were subjected to solution treatment and aging (STA) treatment to obtain a bi-modal microstructure consisting of an equiaxed α phase and lamellar α+β phases, and those to solution treatment and quenching (STQ) treatment to obtain a bi-modal microstructure consisting of equiaxed α-phase and acicular α’-phase. Disks were cut from those rods and were processed by HPT under a pressure of 6 GPa. After HPT processing through 20 revolutions, the alloy with each of the three initial microstructures showed ultrafine grains with a size of ~70 nm. The alloy resulted in a higher tensile strength (1350 MPa) in both the bi-modal microstructures than that (1250 MPa) in the alloy with equiaxed α+β microstructure after HPT processing. It was shown that the Ti-6Al-7Nb alloy with the bi-modal microstructure was strengthened more than with the equiaxed α+β microstructure when the alloy was processed by HPT. Furthermore, the alloy with bi-modal microstructure consisting of equiaxed α-phase and acicular α’-phase showed a good balance between the tensile strength (1280 MPa) and the elongation to fracture (22%) after HPT processing through 1 revolution. In summary, therefore, large strength and elongation of the Ti-6Al-7Nb alloy were simultaneously achieved by HPT processing.

Wear Performance Evaluation of Minimum Quantity Lubrication With Exfoliated Graphite Nanoplatelets in Turning Titanium Alloy

This paper evaluates the performances of dry, minimum quantity lubrication (MQL), and MQL with nanofluid conditions in turning of the most common titanium (Ti) alloy, Ti-6Al-4 V, in a solution treated and aged (STA) microstructure. In particular, the nanofluid evaluated here is vegetable (rapeseed) oil mixed with small concentrations of exfoliated graphite nanoplatelets (xGnPs). This paper focuses on turning process that imposes a challenging condition to apply the oil or nanofluid droplets directly onto the tribological surfaces of a cutting tool due to the uninterrupted engagement between tool and work material during cutting. A series of turning experiments was conducted with uncoated carbide inserts, while measuring the cutting forces with a dynamometer under the dry, MQL and MQL with nanofluid conditions supplying oil droplets externally from our MQL device. The inserts are retrieved intermittently to measure the progress of flank and crater wear using a confocal microscopy. This preliminary experimental result shows that MQL and in particular MQL with the nanofluid significantly improve the machinability of Ti alloys even in turning process. However, to attain the best performance, the MQL conditions such as nozzle orientation and the concentration of xGnP must be optimized.

Recent Advances in the Design and Fabrication of Strong and Ductile (Tensile) Titanium Metal Matrix Composites

Titanium metal matrix composites (TiMMCs) offer much improved strength, elastic modulus, and wear resistance at both room and elevated temperatures but often at the expense of tensile ductility, which excludes them from most key engineering applications. Recent advances show that this long‐standing strength‐ductility dilemma can be controlled to a large extent by adopting novel design concepts based on powder metallurgy (PM). These include: 1) reinforcing the Ti matrix with a three‐dimensional (3D) network‐like architecture of TiB whiskers or nanowires; 2) the use of nanostructured carbon precursors (nanotubes, fibers, and graphene) to enable in situ formation of TiC reinforcements; and 3) the exploitation of “ductility‐detrimental” interstitial elements (O, N, H) for strengthening. On a laboratory scale, the fabricated TiMMCs all exhibit an excellent combination of tensile strength and elongation, comparable to, or even better than, solution‐treated and aged (STA) wrought Ti–6Al–4V. The mechanisms behind these novel developments are analyzed. New insights into the design and fabrication of stronger and more ductile (tensile) TiMMCs are offered.

Microstructural influence on fatigue crack propagation during high cycle fatigue testing of additively manufactured Alloy 718

A study of the microstructure of additively manufactured Alloy 718 was performed in order to better understand the parameters that have an influence on the fatigue properties of the material. The specimens were manufactured using two powder bed fusion techniques – Electron Beam Melting (EBM) and Selective Laser Melting (SLM). Four point bending fatigue tests were performed at room temperature with a stress ratio of R = 0.1 and 20 Hz frequency, on material that was either in hot isostatically pressed (HIP) and solution treated and aged (STA) condition or in STA condition without a prior HIP treatment. The grains in the SLM material in the HIP + STA condition have grown considerably both in the hatch and the contour regions; EBM material, in contrast, shows grain growth only in the contour region. Fractographic analysis of the specimens in HIP + STA condition showed a faceted appearance while the specimens in STA condition showed a more planar crack appearance. The crack propagation occurred in a transgranular mode and it was found that precipitates such as NbC, TiN or δ-phase, when present, did not affect the crack path. The areas with larger grains corresponded to the faceted appearance of the fracture surface. This could be attributed to the plastic zone ahead of the crack tip being confined within one grain, in case of the larger grains, which promotes single shear crack growth mode.

The Effect of Post-Processes on the Microstructure and Creep Properties of Alloy718 Built Up by Selective Laser Melting.

The selective laser melting (SLM) process was used to fabricate an Alloy718 specimen. The microstructure and creep properties were characterized in both the as-built and post-processed SLM materials. Post-processing involved several heat treatments and a combination of hot isostatic pressing (HIP) and solution treatment and aging (STA) to homogenize the microstructure. The experimental results showed that the originally recommended heat treatment process, STA-980 °C, for cast and wrought materials was not effective for SLM-processed specimens. Obvious grain growth structures were obtained in the STA-1180 °C/1 h and STA-1180 °C/4 h specimens. However, the grain size was uneven since heavy distortion or high-density dislocation formed during the SLM process, which would be harmful for the mechanical properties of SLM-fabricated materials. The HIP+ direct aging process was the most effective method among the post-processes to improve the creep behavior at 650 °C. The creep rupture life of the HIP+ direct aging condition approached 800 h since the HIP process had the benefit of being free of pores, thus preventing microcrack nucleation and the formation of a serrated grain boundary.

The Effect of Heat Treatments on Microstructure and Mechanical Properties of As-Extruded Ti-6Al-4V Alloy Rod from Blended Elemental Powders

In this study, Ti-6Al-4V bars were first prepared by extrusion of powder compacts from blended powder mixtures in the beta phase region, then the as-extruded bars were heat-treated following four different conditions: beta quenching and aging (βQA), broken up structure (BUS) treatment, solution treatment and aging (STA) and recrystallization annealing (RA). The effect of the heat treatments on microstructure and mechanical properties was studied using optical microscopy, scanning electron microscopy, and mechanical test to determine which heat-treatment condition has the greatest impact on the mechanical properties of the as-extruded Ti-6Al-4V alloy. The results show that the as-extruded condition has the best balance of strength (1120 MPa of UTS) and ductility (11% of elongation to failure). βQA and STA lead to a slight increase in strength but ductility decreases considerably. After BUS and RA treatments, both strength and ductility are reduced. The relationship between processing, microstructure and properties was studied, and their implications towards fatigue behaviour and fracture toughness were discussed.

High-tensile-strength and ductile novel Ti-Fe-N-B alloys reinforced with TiB nanowires

In this study, we designed and fabricated high-performance Ti-Fe-N-B alloys by sintering a blend of Ti powder, Fe powder and BN nanopowder using spark plasma sintering. During sintering, TiB nanowires nucleated from the surfaces of Ti powder particles on which the BN nanoparticles were dispersed, and then grew into the nearby Ti matrix forming a three-dimensional (3D) network-woven architecture throughout the Ti matrix. The TiB nanowires were about 10–30µm in length and 50–200nm in diameter after sintering. Their existence suppressed the formation of the continuous α-Ti phase along the β-Ti grain boundaries and refined the microstructure of the Ti matrix. A large quantity of α-Ti nanoplates precipitated along the planes (110)β-Ti in the Ti-Fe-N-B alloys. The as-sintered Ti-4.5Fe-0.14N-0.11B alloy achieved a high tensile strength of 1176MPa with a significant tensile elongation of 10.4%, which satisfied the requirements for the tensile properties of mill-annealed Ti6Al4V in the solution-treated and aged (STA) condition. The TiB nanowires, α-Ti nanoplates, Fe solute atoms, and N solute atoms in the matrix all contributed to the high tensile strength.