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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

The Role of Friction Stir Welding on the Microstructure and Mechanical Properties of AZ31B-H24 Mg alloy

In this study, an attempt was made to join AZ31B magnesium alloy by friction stir welding (FSW) process. A single tool with cylindrical screw threaded pin was used to investigate the effect of welding parameters on microstructure and mechanical properties of stir zone (SZ). Several welds were made at different rotational ({omega}) and traverse ({upsilon}) speeds, while the {omega}/{upsilon} ratios were kept constant. The optical and scanning electron microscopy were used to study the variation of microstructure across the welds. Moreover, micro-hardness and tensile tests were carried out to evaluate the mechanical properties of joints. It was found that {omega} plays more significant role on the resulted grain structure than {upsilon}, and at a constant {omega}/{upsilon} ratio, decreasing rotational speed decreased the size of grains, and hence, improved the hardness value and the tensile strength of the SZ.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Flow Patterns, Microstructure and Mechanical Properties of AZ31/Al6061 Dissimilar Friction Stir-Welded Joints

Dissimilar joints between die-cast AZ31 and extruded Al6061-T6 were joined using friction stir welding technology at a constant transverse speed (50 mm/min) and rotation rate of 800 or 1000 rpm. The flow patterns, microstructure evolution and intermetallic compounds in dissimilar joints were studied by optical and scanning electron microscopy. The relationship between microstructure and tensile properties was analyzed. The microhardness distribution along the horizontal centerline in cross section was investigated. Local flow without obvious mixing existed between Mg and Al metals in the tool shoulder-affected zone. For the tool-pin-affected zone, two typical zones, namely, the “extrusion zone” and “flow zone” existed because of the different flow modes of the plastic metals. The phase analysis showed that intermetallic compounds, including Al{sub 12}Mg{sub 17} and Al{sub 3}Mg{sub 2} formed in banded structures. Phase analysis showed that a joint with welding parameters of 800 rpm and 50 mm/min (Joint-500) had good mechanical properties because of the more uniform microstructure distribution and fewer intermetallic compounds. Fracture analysis indicated some microvoids and lamellate intermetallic compounds in the fracture surface of the joint with welding parameters of 1000 rpm and 50 mm/min (Joint-1000), which deteriorated its tensile strength significantly.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Cost-Effective Thermomechanical Processing of Nanostructured Ferritic Alloys: Microstructure and Mechanical Properties Investigation

Nanostructured ferritic alloys (NFAs), such as oxide-dispersion strengthened (ODS) alloys, play a vital role in advanced fission and fusion reactors, offering superior properties when incorporating nanoparticles under irradiation. Despite their importance, the high cost of mass-producing NFAs through mechanical milling presents a challenge. This study delves into the microstructure-mechanical property correlations of three NFAs produced using a novel, cost-effective approach combining severe plastic deformation (SPD) with the continuous thermomechanical processing (CTMP) method. Analysis using scanning electron microscopy (SEM)-electron backscatter diffraction (EBSD) revealed nano-grain structures and phases, while scanning transmission electron microscopy (STEM)-energy dispersive X-ray spectroscopy (EDS) quantified the size and density of Ti-N, Y-O, and Cr-O fine particles. Atom probe tomography (APT) further confirmed the absence of finer Y-O particles and characterized the chemical composition of the particles, suggesting possible nitride dispersion strengthening. Correlation of microstructure and mechanical testing results revealed that CTMP alloys, despite having lower nanoparticle densities, exhibit strength and ductility comparable to mechanically milled ODS alloys, likely due to their fine grain structure. However, higher nanoparticle densities may be necessary to prevent cavity swelling under high-temperature irradiation and helium gas production. Further enhancements in uniform nanoparticle distribution and increased sink strength are recommended to mitigate cavity swelling, advancing their suitability for nuclear applications.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Microstructure and Mechanical Properties of Mg{sub 2}Si/AZ91 Composites In Situ Synthesized by Using Silica Fume as the Si Source

Microstructure and mechanical properties of in situ Mg{sub 2}Si/AZ91 composites fabricated using silica fume as the Si source were investigated. The composites contained α-Mg, network Mg{sub 17}Al{sub 12}, lamellar Mg{sub 17}Al{sub 12}, coarse polygonal Mg{sub 2}Si and needle-type Mg{sub 2}Si. Mischmetal modification eliminated the coarse polygonal Mg{sub 2}Si and resulted in a decreased amount of lamellar Mg{sub 17}Al{sub 12} and refined matrix grain size. Solution and aging treatment made the network Mg{sub 17}Al{sub 12} transform into lamellar Mg{sub 17}Al{sub 12}. As the volume fraction of Mg{sub 2}Si increased, the matrix grain size decreased, the amount of Mg{sub 17}Al{sub 12} increased, and more Mg{sub 17}Al{sub 12} precipitated in grain interiors as a result of the increased Al/Mg ratio caused by increasing the amount of Mg{sub 2}Si. The tensile strength and elastic modulus were much higher for the modified composites than for the unmodified one and increased by both increasing the volume fraction of Mg{sub 2}Si and performing aging treatment. The composites failed in a quasi-cleavage fracture mode, and coarse polygonal Mg{sub 2}Si phases were responsible for the lowest ductility of the unmodified composite. The highest UTS of 291.55 MPa obtained is much higher than those reported so far by using fly ash as the Si source, indicating that silica fume is more suitable as the Si source to synthesize Mg{sub 2}Si/AZ91 composites.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Replication of engine block cylinder bridge microstructure and mechanical properties with lab scale 319 Al alloy billet castings

In recent years, aluminum alloy gasoline engine blocks have in large part successfully replaced nodular cast iron engine blocks, resulting in improved vehicle fuel efficiency. However, because of the inadequate wear resistance properties of hypoeutectic Al–Si alloys, gray iron cylinder liners are required. These liners cause the development of large tensile residual stress along the cylinder bores and necessitate the maximization of mechanical properties in this region to prevent premature engine failure. The aim of this study was to replicate the engine cylinder bridge microstructure and mechanical properties following TSR treatment (which removes the sand binder to enable easy casting retrieval) using lab scale billet castings of the same alloy composition with varying cooling rates. Comparisons in microstructure between the engine block and the billet castings were carried out using optical and scanning electron microscopy, while mechanical properties were assessed using tensile testing. The results suggest that the microstructure at the top and middle of the engine block cylinder bridge was successfully replicated by the billet castings. However, the microstructure at the bottom of the cylinder was not completely replicated due to variations in secondary phase morphology and distribution. The successful replication of engine block microstructure will enable the future optimization of heat treatment parameters. - Highlights: • A method to replicate engine block microstructure was developed. • Billet castings will allow cost effective optimization of heat treatment process. • The replication of microstructure in the cylinder region was mostly successful. • Porosity was more clustered in the billet castings compared to the engine block. • Mechanical properties were lower in billet castings due to porosity and inclusions.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Effect of Heat Treatment on Microstructure and Mechanical Properties of Stellite 12 Fabricated by Laser Additive Manufacturing

Microstructure evolution and wear resistance of Stellite 12 produced by laser additive manufacturing were studied in untreated and heat-treated conditions. In untreated conditions, cobalt matrix dendrites and inter-dendritic eutectic carbides were the primary microstructure, blocky and lamellar eutectic carbides can be found, and M{sub 7}C{sub 3} and M{sub 23}C{sub 6} are the primary carbides. Heat treatment can modify the microstructure of this alloy. Primary carbides were dissolved into the cobalt matrix after solution treatment. Aging treatment resulted in the precipitation of carbides, the transformation of M{sub 7}C{sub 3} into M{sub 23}C{sub 6} carbides, and the increase in microhardness. Solution and aging treatment can also cause the precipitation of carbides, but the morphology and distribution of carbides were absolutely different. The wear resistance of untreated samples at room temperature (RT) and 600 °C is better than that at 200 and 400 °C due to the high hardness at RT and the formation of oxide film at 600 °C. The wear resistance of heat-treated samples was tested at 600 °C; it was dominated by the formation and flake-off of oxide film. The sample that underwent solution plus aging treatment has a superior wear resistance.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Influence of Austenitizing Temperature on the Microstructure and Mechanical Properties of an Fe-Cr-Ni-Mo-Ti Maraging Stainless Steel

The influence of austenitizing temperature on the microstructure and mechanical properties of an Fe-Cr-Ni-Mo-Ti maraging stainless steel was investigated. The grain size, Laves phase, and retained austenite in steels given different solution treatments were observed using optical microscopy, scanning electron microscopy, and x-ray diffraction. Relationships with mechanical properties were measured by tensile testing. The grain growth rate was relatively slow at temperatures of 800-1000 °C then rapidly increased at higher temperatures. Low-temperature austenitization augmented the retention of austenite, the fraction of which decreased with an increase in austenitizing temperature. The Laves phases, which precipitated in austenite during austenitization at 800-900 °C, were preserved after quenching. The solution treatment had a significant effect on the final tensile properties of the steel after aging, due to the presence of retained austenite and Laves phase reducing its strength.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Brazing ZrO{sub 2} ceramic to Ti–6Al–4V alloy using NiCrSiB amorphous filler foil: Interfacial microstructure and joint properties

Reliable brazing of ZrO{sub 2} ceramic and Ti–6Al–4V alloy was achieved using NiCrSiB amorphous filler foil. The interfacial microstructure of ZrO{sub 2}/Ti–6Al–4V joints was characterized by scanning electron microscope, energy dispersive spectrometer and micro-focused X-ray diffractometer. The effects of brazing temperature on the interfacial microstructure and joining properties of brazed joints were investigated in detail. Active Ti of Ti–6Al–4V alloy dissolved into molten filler metal and reacted with ZrO{sub 2} ceramic to form a continuous TiO reaction layer, which played an important role in brazing. Various reaction phases including Ti{sub 2}Ni, Ti{sub 5}Si{sub 3} and β-Ti were formed in brazed joints. With an increasing of brazing temperature, the TiO layer thickened gradually while the Ti{sub 2}Ni amount reduced. Shear test indicated that brazed joints tend to fracture at the interface between ZrO{sub 2} ceramic and brazing seam or Ti{sub 2}Ni intermetallic layer. The maximum average shear strength reached 284.6 MPa when brazed at 1025 °C for 10 min. - Graphical Abstract: Interfacial microstructure of ZrO{sub 2}/TC4 joint brazed using NiCrSiB amorphous filler foil was: ZrO{sub 2}/TiO/Ti{sub 2}Ni + β-Ti + Ti{sub 5}Si{sub 3}/β-Ti/Widmanstätten structure/TC4. - Highlights: • Brazing of ZrO{sub 2} ceramic and Ti-6Al-4V alloy was achieved. • Interfacial microstructure was TiO/Ti{sub 2}Ni + β + Ti{sub 5}Si{sub 3}/β/Widmanstätten structure. • The formation of TiO produced the darkening effect of ZrO{sub 2} ceramic. • The highest joining strength of 284.6MPa was obtained.

36 MATERIALS SCIENCE↗
DOE OSTI2016

The comparison of microstructures and mechanical properties between 14Cr-Al and 14Cr-Ti ferritic ODS alloys

In this study, two kinds of 14Cr ODS alloys (14Cr-Al and 14Cr-Ti) were investigated to reveal the different effects between Al and Ti on the microstructures and mechanical properties of 14Cr ferritic ODS alloys. The microstructure information such as grains, minor phases of these two alloys has been investigated by high-energy X-ray diffraction and transmission electron microscopy (TEM). The in situ synchrotron X-ray diffraction tensile test was applied to investigate the mechanical properties of these two alloys. The lattice strains of different phases through the entire tensile deformation process in these two alloys were analyzed to calculate their elastic stresses. From the comparison of elastic stress, the strengthening capability of Y 2 Ti 2 O 7 is better than TiN in 14Cr-Ti, and the strengthening capability of YAH is much better than YAM and AlN in 14Cr-Al ODS. The dislocation densities of 14Cr-Ti and 14Cr-Al ODS alloys during tensile deformation were also examined by modified Williamson-Hall analyses of peak broadening, respectively. In conclusion, the different increasing speed of dislocation density with plastic deformation reveals the better strengthening effect of Y-Ti-O particles in 14Cr-Ti ODS than that of Y-Al-O particles in 14Cr-Al ODS alloy.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Effect of Ni Addition to Sn0.7Cu Solder Alloy on Thermal Behavior, Microstructure, and Mechanical Properties

The addition of Ni on lead-free solder alloys Sn0.7Cu was tested in this study. A small amount of Ni was added to the solder alloys to evaluate the thermal behavior, microstructure, and mechanical properties of the composite solders after sintering and isothermal aging for 3 days and then compared with the results of the binary Sn0.7Cu solder. The results indicated that the ultimate tensile strength and yield tensile strength changed when adding 0.25 wt.% of Ni. The tested results of the differential scanning calorimeter showed that the addition of Ni (such as 0.5 and 1 wt.%) could obviously increase the solidification temperature of Sn0.7Cu alloys in the cooling process. When the Ni content was increased to 0.25 wt.% in the ternary condition, which includes the Sn0.7Cu-xNi (x = 0, 0.1, 0.25, 0.5, and 1 wt.%) solder alloys for the indentation creep test, the minimum creep rate reached the maximum; however, the trend was reversed as the Ni content was higher than this level. In addition, the microstructure of Sn-0.7Cu-xNi solder alloys was obviously different with the eutectic Sn-0.7Cu solder, such that the Ni gradually accumulated in the (Cu, Ni){sub 6}Sn{sub 5} IMCs within the Ni-containing solder alloys. Additionally, this process refined the microstructure of the Sn-0.7Cu solder. The fracture surface of the eutectic Sn-0.7Cu solder revealed ductile fracture modes; however, there was no mixed ductile–brittle fracture mode occurred when the Ni content was in the range of 0-1 wt.%.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Correlating microstructure and mechanical properties of harvested high dose Zorita light water reactor internals

Here, in this study, microstructural studies and micro-mechanical testing of an ex-plant material harvested from the decommissioned pressurized water reactor (PWR) is carried out. Irradiated 304 stainless steel (SS) components were harvested by the Electric Power Research Institute, U.S. Nuclear Regulatory Commission, and members of the José Cabrera Nuclear Power Station (Zorita) in Spain. The bi-crystalline micro-tensile specimens, atom probe tomography (APT) tips, and transmission electron microscopy (TEM) lamellae were fabricated from the baffle plate materials irradiated to 0.05, 15 and 50 dpa to elucidate microstructural, microchemical, and local mechanical properties changes as a function of dose. TEM and APT studies reveal radiation induced Ni, Cr, and Si rich precipitates in the 15 dpa sample that become smaller and partially redissolve into the matrix of the 50 dpa sample (decreasing size and number density). Dislocation loop and cavity number density and size were quantified as a function of dose as well as swelling. Intergranular Ni and Si enrichments with concomitant Fe and Cr depletion were observed in the 15 dpa sample and were more pronounced in the 50 dpa sample. Micro-tensile testing performed in the scanning electron microscope (SEM) at room temperature and 300 °C shows that the material's local yield strength and ultimate tensile strength decreases with increased dose and elevated test temperature and provides further insights via localized strain mapping. Current and previous mechanical data was compared with calculated values using the dispersed barrier hardening model with inputs of dislocation loops, precipitates, and cavities from microstructural characterization.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Comparative investigation on microstructures and mechanical properties of (TiB + TiC)/Ti-6Al-4V composites from Ti-B4C-C and Ti-TiB2-TiC systems

Highlights: • The (TiB{sub w}+TiC{sub p})/Ti-6Al-4V composites were fabricated from Ti-B{sub 4}C-C and Ti-TiB{sub 2}-TiC systems by reactive hot-pressed sintering. • Microstructures and mechanical properties of the two kinds of composites were comparatively investigated. • The composites from Ti-TiB{sub 2}-TiC system possess higher elastic modulus and Vickers hardness than those from Ti-B{sub 4}C-C system. • The composites from Ti-TiB{sub 2}-TiC system have higher bending strength than the other system while employing same conditions. • The composites from Ti-B{sub 4}C-C system present better abrasion resistance than those from Ti-TiB{sub 2}-TiC system. - Abstract: Two percentages of TiB + TiC reinforced Ti-6Al-4V composites from Ti-B{sub 4}C-C and Ti-TiB{sub 2}-TiC systems were fabricated by reactive hot-pressed sintering. Their microstructures and mechanical properties involving elastic modulus, Vickers hardness, bending strength and wear property were investigated comparatively. The experimental results show that needle-like TiB whiskers and near-equiaxed TiC particles are evenly distributed in the Ti-6Al-4V matrix. The mechanical properties of the (TiB + TiC)/Ti-6Al-4V composites are closely related with the nominal composition and synthesis system of TiB + TiC reinforcement and the microstructures of composites. With increasing the nominal volume fraction of reinforcement, both elastic modulus and Vickers hardness increase more or less and the bending strength decreases in varying degrees. A certain increase of pores in the composites with the sintering temperature increasing to 1300 °C can markedly affect the bending strength. Moreover, no matter what the sintering temperature and nominal volume fraction of reinforcement, the elastic modulus and Vickers hardness of composites from the Ti-TiB{sub 2}-TiC system are higher than those from the Ti-B{sub 4}C-C system. Similarly, the composites from the Ti-B{sub 4}C-C system present better abrasion resistance than those from the Ti-TiB{sub 2}-TiC system due to the difference of interfacial bonding between the TiC particles and Ti-6Al-4V matrix in the two kinds of composites.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Optimization of the microstructure and mechanical properties of electron beam welded high-strength medium-entropy alloy (NiCoCr) 94 Al 3 Ti 3

For this work, the weldability and effects of subsequent heat treatment on the microstructure and mechanical properties of the medium-entropy alloy (MEA) (NiCoCr) 94 Al 3 Ti 3 have been explored using electron beam welding (EBW). It was found that EBW joints consist of a supersaturated f.c.c. matrix with coarse, asymmetric columnar grains (17.7–24 μm). The fraction of twins and Σ3 n CSL boundaries in weld joints was only 10% of that in the base metal, a value which increased to 30% after aging at 800 °C. The aging also led to improvements in the hardness, tensile strength, and work hardening rate, a result of the precipitation of a high volume fraction (0.29–0.33) of ultrafine (15–17.4 nm dia.) coherent spherical L1 2 -structured particles. The contributions of the L1 2 nanoparticles and Hall-Petch strengthening to the yield strength were estimated to be 537–573 MPa and 105–123 MPa, respectively. The MEA shows excellent weldability and, after aging, good strength (YS~1098 MPa, UTS~1368 MPa) and elongation to failure (~11%) by ductile fracture.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Microstructure and Mechanical Properties of Ni-Based Superalloy Nimonic 105 with Varying Carbon Content

High carbon levels have been found to improve the fabricability of high-strength cast and wrought Ni-based superalloys, enabling the development of superior cast/wrought materials. However, carbon also strongly influences the microstructure and mechanical properties of the alloys. Nimonic 105 variants with three different carbon concentrations were manufactured. A bimodal grain size was found in the intermediate carbon content variant, while the high (low) carbon resulted in fine (coarse) grains thereby significantly affecting creep performance. The variations in grain structure were attributed to the primary carbides. An intermediate carbon level showed the best combination of strength and ductility in tension at high-temperature but little improvement in, or even inferior, creep performance. Discussion of the results will establish an understanding of the influence of carbon on the microstructure and mechanical properties of high strength cast and wrought superalloys, providing insights into obtaining high-quality alloys for future high-temperature applications.

Fang, Xiaotian↗
DOE OSTI2018

Effect of Rolling Temperature on the Microstructure and Tensile Properties of 47Zr-45Ti-5Al-3V Alloy

The 47Zr-45Ti-5Al-3V (wt.%) alloy was solution-treated at 850 and 780 °C for 30 min and then rolled at different temperatures. The effect of rolling temperature on microstructure and tensile properties was investigated. The results showed that the microstructure contained a large amount of α phase at a rolling temperature of 600 °C. As the rolling temperature increased, the amount of α phase decreased, whereas the amount of β phase increased. When the rolling temperature was higher than 700 °C, the alloy was composed of a single β phase. The tensile properties of the alloy depended strongly on rolling temperature. The yield strength and tensile strength decreased with increasing rolling temperature, whereas the elongation increased. At a given rolling temperature, low solution treatment temperature resulted in higher strength and lower elongation than high solution treatment temperature. The fracture mode changed from cleavage fracture and quasi-cleavage fracture to dimple fracture with increasing rolling temperature.

36 MATERIALS SCIENCE↗
DOE OSTI2022

The effects of aluminum concentration on the microstructural and electrochemical properties of lithium lanthanum zirconium oxide

Cubic lithium lanthanum zirconium oxide (Li 7-x Al x La 3 Zr 2 O 12 , LLZO) garnet has gained attention as a promising next-generation electrolyte for lithium batteries due to its high ionic conductivity and chemical stability with lithium metal. The high conductivity can be achieved through doping over a range of aluminum concentrations. In this study, we hot-pressed samples to achieve <2% nominal porosity with aluminum concentrations from x = 0.25–0.55 mol to understand the effect of aluminum on microstructure and electrochemistry. It was observed that beyond the aluminum solubility limit (x = ~0.40), resistive secondary phases formed at the grain boundaries. As a result, the percent grain boundary resistance increased from 17.6 to 41.2% for x = 0.25 and x = 0.55, respectively. Both the grain boundary and bulk activation energies remained relatively constant as the aluminum concentrations increased (~0.44 eV and ~0.39 eV, respectively). It was, therefore, surmised that the mobility term of the Nernst–Einstein equation was roughly independent of aluminum concentration and the major variable controlling bulk conductivity was the number of lithium charge carriers. As a result, as the aluminum concentration increased from x = 0.25 to x = 0.55 the bulk conductivity decreased from 0.56 to 0.15 mS cm -1 . Following these trends of increasing grain boundary resistance and decreasing bulk conductivity with increasing aluminum concentration, x = 0.25 had the highest total conductivity (0.46 mS cm -1 ). We demonstrated that aluminum concentration has a significant effect on the microstructure and electrochemical properties of LLZO. In conclusion, we believe this work could help understand how to link processing, microstructure, and electrochemical properties to guide the manufacturing of LLZO for use in solid-state batteries.

25 ENERGY STORAGE↗
DOE OSTI2013

Microstructure and mechanical properties of Ti–B–C–N–Si nanocomposite films deposited by unbalanced magnetron sputtering

Quinary Ti–B–C–N–Si nanocomposite thin films were deposited on AISI 304 stainless steel substrates by d.c. unbalanced magnetron sputtering from a TiB{sub 2}–TiC compound target and a pure Si target. The relationship between microstructure and mechanical properties of the films was investigated in terms of the nanosized crystallites/amorphous system. The synthesized Ti–B–C–N–Si films were characterized using x-ray diffraction, x-ray photoelectron spectroscopy, atomic force microscopy, and high resolution transmission electron microscopy. The results showed that the Ti–B–C–N–Si films were nanocomposites composed of nanosized TiB{sub 2}, TiC, and TiSi{sub 2} crystallites (2-3 nm in size) embedded in an amorphous matrix. The addition of Si to the Ti–B–C–N film led to precipitation of nanosized crystalline TiSi{sub 2} and percolation of amorphous SiC phases. The Ti–B–C–N–Si films with up to 7 at. % Si content presented high hardness (≥35 GPa), H/E (≥0.0095), and W{sub e} (>50%) with compressive residual stress (∼0.5 GPa). A systematic investigation on the microstructure and mechanical properties of Ti–B–C–N–Si films containing different Si contents is reported.

36 MATERIALS SCIENCE↗
DOE OSTI2017

From Solidification Processing to Microstructure to Mechanical Properties: A Multi-scale X-ray Study of an Al-Cu Alloy Sample

We follow an Al-12 at. pct Cu alloy sample from the liquid state to mechanical failure, using in situ X-ray radiography during directional solidification and tensile testing, as well as three-dimensional computed tomography of the microstructure before and after mechanical testing. The solidification processing stage is simulated with a multi-scale dendritic needle network model, and the micromechanical behavior of the solidified microstructure is simulated using voxelized tomography data and an elasto-viscoplastic fast Fourier transform model. This study demonstrates the feasibility of direct in situ monitoring of a metal alloy microstructure from the liquid processing stage up to its mechanical failure, supported by quantitative simulations of microstructure formation and its mechanical behavior.

36 MATERIALS SCIENCE↗