Reduction In Yield Strength Research Articles

In Situ Development and High Temperature Features of CoCrFeNi-M6Cp High Entropy-Alloy Based Hardmetal

In this work, an in-situ CoCrFeNi-M6Cp high entropy-alloy (HEA) based hardmetal with a composition of Co25Cr21Fe18Ni23Mo7Nb3WC2 was fabricated by the powder metallurgy (PM) method. Microstructures and mechanical properties of this HEA were characterized and analyzed. The results exhibit that this HEA possesses a two-phase microstructure consisting of the face-centered cubic (FCC) matrix phase and the carbide M6C phase. This HEA has an average grain size of 2.2 μm, and the mean size and volume fraction of carbide particles are 1.2 μm and 20%. The tensile tests show that the alloy has a yield strength of 573 MPa, ultimate tensile strength of 895 MPa and elongation of 5.5% at room temperature. The contributions from different strengthening mechanisms in this HEA were calculated. The grain boundary strengthening is the dominant strengthening mechanism, and the carbide particles are significant for the further enhancement of yield strength by the dislocation strengthening and Orowan strengthening. In addition, with increasing temperatures from 600 °C to 900 °C, the HEA shows a reduced yield strength (YS) from 473 MPa to 142 MPa, a decreased ultimate tensile strength (UTS) from 741 MPa to 165 MPa and an enhanced elongation from 10.5% to 31%.

Electroplasticity effects in Haynes 230

Electrically-assisted forming has the potential to reduce the cost of hot working Haynes 230 by enabling better material utilization, shorter cycle times and lower energy costs. In this paper, we investigate the presence of an electroplastic effect in Haynes 230 through electrically-assisted and isothermal tensile testing, thermomechanical simulation and microstructural characterization. Experimental results show discernable reductions in yield strength and elongation between a purely thermal response and an electrically-activated thermal response across the space of parameters studied. Evidence of a “rapid aging” effect during the electrically-assisted pulling of Haynes 230 is demonstrated via microstructural characterization. Results suggest that in Haynes 230, localized joule heating is brought on by electron-ion collisions which leads to fast precipitation of solutionized elements that increase subsequent flow stresses compared to an equivalent purely-thermal response without the application of electric current.

Experimental study of the post-fire mechanical properties of Q690 high strength steel

In this paper, the post-fire mechanical properties of Q690 steel obtained experimentally are presented and empirical equations to estimate the post-fire elastic modulus, yield strength, tensile strength and fracture strain are proposed. The variables considered in the present study include the level of temperature exposure (from 300 °C to 900 °C), the cooling methods (natural air and submersion in water) used, the effects of different heating rates, repeated heating and cooling, and different initial loading conditions. The test results show that while the post-fire elastic modulus is not too sensitive to the exposed temperature level and the manner of cooling, it decreases about 10% when a higher initial heating rate, repeated heating and cooling, or a load is applied to the specimen. The post-fire yield strength tends to decrease with the exposed temperature level when the temperature reaches 400 °C if the air cooling method is used and 500 °C if the water quenching method is used. Further reduction in yield strength occurs when the specimen is subjected to a higher initial heating rate, repeated heating and cooling, or an applied load. The post-fire tensile strength does not show significant variations if air cooling is used but for specimens heated to a temperature above 700 °C and rapidly cooled by submersion in water, noticeably higher post-fire tensile strength is observed as a result of the formation of martensite. Martensite formation also reduces the ductility (as measured by the fracture strain) of steel heated above 700 °C and cooled suddenly.

In vivo analysis of bone-tissue interface in medical grade titanium and porous titanium with and without cenosphere as space holder

The present study aims at understanding the in vivo behavior of titanium (Ti) foam (with and without addition of cenosphere as space holder) developed by powder metallurgy route which follows compaction at an applied pressure of 100 MPa and sintering at 1100 °C for 4 h. Cenosphere with the particle size 150–212 µm was used as spaceholder and its content was 20 wt%. The porosity content of the titanium foam developed in the present study with and without addition of cenosphere was 40% and 27%, respectively. However, they possess reduced yield strength in compression as compared to medical grade titanium. In vivo study was carried out by implanting the samples in bone defect of rabbit femur. All the titanium based samples were well-integrated within the host bone tissue which is revealed in radiography and micro-CT (µ-CT) images of the implants after three months of insertion. Fluorochrome labeling using oxytetracycline marker showed better and comparable new osseous tissue formation in medical grade Ti and porous Ti with cenosphere as space holder after three months as compared to porous Ti. The scanning electron microscopic image of the bone sample interface showed strong bonding with the signature of marginal bone in-growth inside the tissue. Finally, the in vivo behavior was correlated with initial microstructure and composition of the material. The performance of the titanium foam was evaluated by the detailed analysis of the physicochemical properties and in vivo behavior.

Variation in dynamic deformation behavior and resultant yield asymmetry of AZ80 alloy with extrusion temperature

In this work, variation in the dynamic recrystallization (DRX) and dynamic precipitation behavior of AZ80 alloy during extrusion due to changes in extrusion temperature was investigated, and the resultant microstructure and yield asymmetry were analyzed. As the extrusion temperature increases from 250 °C to 350 °C, the primary DRX mechanism changes from twin-induced DRX to discontinuous DRX, resulting in an increase in the DRX area fraction and unDRXed grain size. In addition, as the extrusion temperature rises, Mg17Al12 precipitation during extrusion decreases sharply throughout the extruded material. The reduction in the compressive yield strength (CYS) with increasing extrusion temperature is more pronounced than it is for the tensile yield strength (TYS), which ultimately increases the yield asymmetry of the extruded material. The higher extrusion temperature has less of an influence on the TYS due to the promotion of certain hardening effects. On the other hand, the greater reduction in the CYS is attributed to the increased fraction and size of regions in which {101¯2} twins predominantly form and the lower amount of precipitates, which effectively facilitates {101¯2} twinning.

Macro- and microscale investigations of hydrogen embrittlement in X70 pipeline steel by in-situ and ex-situ hydrogen charging tensile tests and in-situ electrochemical micro-cantilever bending test

The effect of hydrogen on the mechanical properties of X70 pipeline steel was investigated by a combination of macro- and microscale approaches. Various tensile tests under vacuum, in-situ H-plasma charging (IHPC), and ex-situ electrochemical H-charging (EEHC) conditions were conducted to elucidate the hydrogen effect in the macroscale approach. All tensile tests were performed inside an environmental scanning electron microscopy (ESEM) chamber. The IHPC, as a novel hydrogen charging technique, was compared with conventional EEHC while uncharged tensile specimens were used as a reference. The results demonstrated that the variations in the IHPC condition were negligible compared to the vacuum condition, whereas the differences in the ex-situ condition were more prominent. Furthermore, susceptibility to hydrogen in the vacuum-ex situ regime was manifested in the reduction of yield strength and ultimate tensile strength. These findings were confirmed by the fractographic analysis, where some of the effects of hydrogen (e.g. the formation of secondary cracks by detrimental inclusions (MnS and Al2O3) and the transition of fracture features from ductile dimples to cleavage patterns) were well illustrated. On the other hand, micro-cantilever bending tests were performed in the air to avoid hydrogen effects and applied inside a miniaturized electrochemical cell to promote hydrogen uptake. The bending results and post-mortem analysis of the tested cantilevers indicated that the hydrogen-reduced flow stress and hydrogen-induced cracking occurred for the H-charged bent cantilever, while only increased plastic behavior occurred for the cantilever bent in the air.

Hysteretic behavior of post fire structural steels under cyclic loading

This paper presents a series of monotonic tensile tests and cyclic loading tests on structural steels after exposure to elevated temperatures. The generally used mild steel Q235, low alloy steel Q345 and high strength steel Q690 were included, and three cooling methods were considered. Strain ascending and strain alternate loading protocols were adopted to investigate the cyclic strength evolution patterns of postfire steels. The strength developments of post fire steels before and after cyclic loadings, and the effect of cyclic loading history and loading protocols on the cyclic strength evolutions were all compared and discussed. The strength evolution was cyclic hardening dominated in Q235 and Q345, and was cyclic softening dominated in Q690. When the experienced temperature exceeding 600 °C, the air-cooled specimens generally had yield strength reduction but also increased extent of cyclic hardening behaviors as the increase of temperature. The reduced tensile strength of postfire steels would be elevated and recovered after cyclic loading. The water-cooled specimens would induce both yield and ultimate strength increase after fire, and the strain hardening behaviors under cyclic loading were also increased. The water spray cooled fire heating specimens presented similar tensile strengths and the cyclic strength evolutions as the untreated ones.

Understanding the process-microstructure correlations for tailoring the mechanical properties of L-PBF produced austenitic advanced high strength steel

In this work, the additive manufacturing technique of laser powder bed fusion (L-PBF) was used to build up X30Mn21 austenitic advanced high strength steel (AHSS) samples. Different L-PBF process parameters were used to understand the correlation between process, microstructure, texture, and mechanical properties. The influence of build platform preheating (200 °C–800 °C), laser speed (550 mm/s - 950 mm/s) and scan strategy (bidirectional continuous and Mark&Sleep (M&S)) on grain size, grain morphology, size of solidification cells, dislocation density, and texture was studied. Local solidification parameters in the melt pool e.g. cooling rates, temperature gradients and solidification velocities were simulated by a FEM heat flow model and correlated with the solidification microstructure. By using SEM/EBSD analysis and tensile testing, the mechanical properties of the AHSS were assessed by considering microstructural aspects. It was found that AHSS, produced with higher laser speeds and an alternative M&S scan strategy, revealed a reduced grain size and texture intensity. This was attributed to a partial columnar to equiaxed transition (CET), as well as a significantly increased density of geometrically necessary dislocations. Preheating of the build platform promoted columnar grain growth with a more pronounced texture, low dislocation densities, and reduced yield strength. The influence of cooling rate, temperature gradient and solidification velocity on microstructural and textural evolution is discussed based on fundamental solidification theories.

Yield-strength prediction of flattened steel pipes by competing Bauschinger effect and strain hardening during pipe-forming

Since flattened steel sheets often show the unexpectedly lower or higher yield strength than leveled sheets, unceasing efforts have been made to accurately predict the yield strength in pipe-forming industries. In the present investigation, the yield strength of line-pipe or casing-pipe steels was predicted by competing Bauschinger effect and strain hardening occurred during the pipe-forming. Yield drop (YD) and yield rise (YR) parameters were newly defined from cyclic simulation analyses of outer and inner walls of pipes to express more reasonably the Bauschinger effect and strain hardening. The YD increased abruptly until the pre-strain of about 1%, and then saturated, while the YR increased linearly with increasing pre-strain. By combining the YD and YR, the variation in yield strength (Δσ) showed a down-and-up behavior as the Bauschinger effect and strain hardening were dominant at low and high pre-strains, respectively, and plausibly explained the relationship of Δσ and piping strain used in pipe-forming industries. According to the microstructural analyses related to the down-and-up Δσ behavior, the polygonal ferrite reduced the yield-strength reduction in the low pre-strain range, whereas the granular bainite or pearlite expanded it. This yield strength prediction coupled with microstructural analyses provide a good idea for designing and reliably predicting the yield strength of in various steel pipes.

A numerical investigation of static resistance of welded planar steel tubular joints under in-plane and out-of-plane bending at elevated temperatures

This study presents the results of a numerical investigation on static resistance of welded planar steel tubular joints under in-plane and out-of-plane bending moments at elevated temperatures. The numerical simulations were carried out using the commercial finite Element software ABAQUS v6.14-1 and the simulation model was validated by comparing against test results for CHS joints under brace in-plane bending at elevated temperatures.Extensive numerical parametric simulations were performed for CHS/SHS/EHS joints under in-plane and out-of-plane bending at elevated temperatures, to establish a database of results covering a wide range of geometrical parameters, including brace to chord diameter ratio, the angle between brace to chord members, and chord diameter to twice chord thickness ratio.The ratios of joint elevated temperature resistance to ambient temperature resistance were compared to the steel yield strength reduction factor, the steel Young’s modulus reduction factor, and the average of the above these reduction factors at different elevated temperatures. Based on the comparisons, it has been found that using the reduction factor for the yield strength of steel to modify the ambient temperature equations will overestimate the resistance of joints at elevated temperatures. As a simplified and safe recommendation, the ambient temperature joint resistance equations can be modified by the average reduction factors for the Young’s modulus and yield strength at elevated temperatures. This modification factor can be increased to the yield strength reduction factor when the brace and chord widths/diameters are the same.

Effect of quenching and tempering temperature on microstructure and tensile properties of microalloyed ultra-high strength suspension spring steel

Effects of quenching-tempering heat treatment on microstructural evolution and fracture behavior of microalloyed high strength suspension spring 55SiCrVNb were investigated. The results showed that an optimal combination of mechanical properties was obtained at the heat-treatment of oil quenching from 900 °C and tempering at 400 °C. Specifically, the ultimate tensile strength, yield strength, elongation and area reduction reached 2021 MPa, 1826 MPa, 10.3% and 42.7%, respectively. With the increasing austenitizing temperature, the grain size increased monotonically with more carbides dissolved in the matrix, and the strength first increased significantly and then decreased slowly. Furthermore, the fracture behavior transformed from ductile fracture to brittle fracture. In addition, the strengths were weakened dramatically as the tempering temperature increased but the elongation and area reduction were enhanced. Three kind of carbides are identified at different tempering temperatures, namely the coherent M2.5C and MC carbides gradually mature into large-sized non-coherent M3C and M7C3 carbides. Moreover, the dislocation reduction, lath boundary and twin martensite decomposition and carbide coarsening were exacerbated at higher tempering temperature while the fracture behavior changed from brittle fracture to ductile fracture.

Microstructure and properties in QCr0.8 alloy produced by selective laser melting with different heat treatment

QCr0.8 alloy is promising in many industrial applications because of its extremely high strength and conductivity. In this study, the influences of heat treatments on the microstructure, mechanical properties, electrical properties and corrosion performances of QCr0.8 alloy fabricated by selective laser melting have been investigated. The results show that a threshold solution heat treatment (SHT) temperature exists. Solid solution only happens when the SHT temperature is higher than the threshold. The threshold SHT temperature is higher than that of cast-state. Solution heat treatment leads to a decrease in the dislocation density and dissolution of the precipitates, which induces a reduction of yield strength and conductivity but an enhancement of ductility and corrosion resistance. After directly aging treatment, the Cr phases precipitate from Cu matrix with the size about 5 nm and have K–S relationship with the matrix. Thus, the strength and conductivity are the highest, while the corrosion resistance is the lowest. Different performance match can be obtained by using different heat treatments. These results provide a guideline for to tailor different properties of selective laser melted Cu–Cr alloys using suitable solid solution and aging treatments.

Time-dependent Seismic Performance Assessment of Corroded Reinforced Concrete Frames

In this study, effects of reinforcement corrosion such as reinforcement cross section reduction, steel yield strength and concrete compressive strength reduction on RC member capacity decrease are studied. Next, a two-dimensional reinforced concrete moment resistant frame is modeled to evaluate the effects of moderate and severe intensity corrosion on moment-curvature behavior of elements and structure seismic response under nonlinear analysis. Structure capacity curves in push-over analysis and failure curves resulted from IDA for both the structure without and with corrosion are obtained and the effects of reinforcement’s corrosion on the reinforced concrete frame seismic performance are determined through comparing the results. The results revealed that in terms of amount, place and type of corrosion in the reinforced concrete frame, value of the reduction resisting moment of elements is different. Furthermore, the outcomes of nonlinear analyses showed that the capacity of structure is reduced and its seismic performance level is changed as a result of corrosion.

Triaxial Limit and Safety Factor of an Anisotropic Corrosion-Resistant Alloy Tubular

Summary Tubulars made with corrosion–resistant alloys (CRAs) exhibit a moderate degree of transverse anisotropy. This results in lower yield strength in the plane perpendicular to the rolling axis of the tubular. In addition, cold work during mill finishing introduces yield strength asymmetry along the axis. The majority of CRA tubulars are low–do/t (≈10–15) production strings. Their design is usually driven by pressure and tension. Given the reduced yield strength in the hoop direction (as compared with axial yield strength), a rigorous method to assess the effect of yield strength anisotropy on the triaxial limits of the pipe is needed. Though there is a substantial body of literature on anisotropy in metals and manufactured composites, anisotropy of tubulars has received minimal attention by tubular designers. In this context, we use Hill's celebrated criterion (Hill 1950) for the yielding of anisotropic metals to develop an equation for the triaxial limits of a hollow cylinder and show that the currently used isotropic triaxial ellipse is a special case of the general limit. Also, by recognizing that purely elastic load excursions do not alter the yield surface, we extend the aforementioned triaxial limit to tubulars with tension-compression asymmetry along the tube axis. Finally, on the basis of the notion of a strength utilization factor, we propose a method to determine the triaxial safety factor for anisotropic CRA tubulars. This method is consistent with the definition of the triaxial safety factor for isotropic tubulars.

Post-fire mechanical behavior of ASTM A572 steels subjected to high stress triaxialities

The goal of this paper is to understand the post-fire mechanical behavior of ASTM A572 Gr. 50 structural steels cooled from high temperatures using both air-cooling (slow cooling rate) and water-cooling (rapid cooling rate) methods under the influence of high stress triaxiality. In this study, various levels of stress triaxialities in uniaxial tension specimens are achieved by introducing notches in the test specimens. The uniaxial notched test specimens are subjected to temperatures ranging between 500 °C and 1000 °C at 100 °C intervals to simulate fire temperatures. The furnace-heated specimens are then either left outside the furnace for air-cooling or quenched in a water bath in the case of water-cooling method. Uniaxial tension tests are performed on both air and water cooled notched specimens to extract the post-fire mechanical properties. Non-linear finite element analyses are performed to obtain the triaxiality profiles along the critical cross sections of notched specimens by employing hardening curves obtained from post-fire uniaxial tension tests. Moreover, microstructures at selected temperatures are obtained to assess the microstructural changes that caused a significant change in post-fire mechanical properties. It is observed that ASTM A572 steels do no exhibit considerable change in mechanical properties when exposed to temperatures up to 600 °C, for both cooling methods. Beyond 600 °C, air-cooling resulted in a reduction in yield strength and ultimate tensile strength and increase in ductility of ASTM A572 steels. Water-cooling from temperatures beyond 600 °C increased the ultimate tensile strength and decreased the ductility of ASTM A572 steels due to the formation of the martensite phase. High stress triaxiality leads to the reduction in ductility and an increase in yield strength and ultimate tensile strength of ASTM A572 steels in both air-cooled and water-cooled conditions. The combined influence of high stress triaxiality and formation of martensite phase resulted in significant increase of up to 158% in yield strength and up to 172% increase in ultimate tensile strength of ASTM A572 steels that are water-cooled after exposure to temperatures beyond 800 °C. On the other hand, the presence of the high stress triaxiality and water-cooling resulted in up to 89% loss of ductility of ASTM A572 steels specimens that are exposed to temperatures beyond 800 °C.

Microstructures and Mechanical Properties of Low Carbon Steel Hot Rolled in Ferrite Region Based on CSP Line

In this paper, the effect of ferrite region rolling on the microstructure and properties of steel plate heat commercial (SPHC) steel produced by compact strip production (CSP) process was studied in detail. Comparing ferrite rolled sheet with austenite rolled sheet, it was found that the average ferrite grain size of low carbon steel sheet rolled in ferrite region increased from 10.6 to 27.6 µm and the dislocation density was slightly reduced from 1.79 × 1011 to 8.9 × 1010 cm−2. The yield strength of ferrite rolled sheet is 92 MPa lower than that of austenite rolled sheet. The theoretical calculation and experimental results indicates that the coarsening of grains contributes to the 70% reduction of yield strength of ferrite rolled sheet, and the reduction of dislocation density and other strengthening factors account for about 30%. Texture analysis results by electron backscattered diffraction (EBSD) shows that the growth of {001} <110> and {112} <110> component in the texture of ferrite rolled sheet lead to the reduction of and Δr.

A nanotwinned austenite stainless steel with high hydrogen embrittlement resistance

A nanotwinned 304 steel with a favorable combination of strength and ductility has been made in this work through the dynamic plastic deformation (DPD) treatment followed by a proper heat treatment. The DPD, DPD-annealed and coarse grain (CG) 304 samples were tensile tested with slow strain rate under electrochemical hydrogen charging condition. Compared with CG sample, DPD-annealed sample with a mixed structure of nanotwins (41% volume fraction), recrystallization grain (RXG, 32% volume fraction) and dislocation structures (27% volume fraction) possesses a high HE resistance. Hydrogen causes a 12.5% reduction in yield strength and 5.4% reduction in tensile strength of DPD-annealed sample because hydrogen enhances dislocations/twin boundaries (TBs) interactions and the subsequent dislocation mobility during the TB-mediated slip transfer. Hydrogen charging also causes a 41% reduction in strain induced martensite of DPD-annealed sample. Strain localization is supposed to be mitigated by the bundle form of TBs and the micro-sized RXGs, accounting for the high HE resistance of DPD-annealed alloy. Our findings suggest a new strategy to design high strength alloys with low HE susceptibility.

Higher modes contribution for estimating the inelastic deformation ratios and seismic demands of structures

In order to estimate the seismic demand by using the nonlinear static procedure, different approximate methods have been developed. One of the most useful methods is called displacement coefficient method (DCM), which is based on some modification factors. One of these coefficients denoted C1, concerns the inelastic deformation ratio and usually depends on either the yield-strength reduction factor or the ductility factor. In general the evaluation of the inelastic deformation ratio is based on the response of single degree of freedom (SDOF) systems, where the response of the structure is mainly controlled by the fundamental mode, knowing that the inelastic deformation ratio will not capture the contribution of higher modes in the overall structural response. A developed theoretical approach with the aim of estimating the inelastic deformation ratio for structures, considering contribution of higher modes of vibration, is introduced. In this assessment, the normalized yield strength coefficient (η) and the post-to-preyield stiffness ratio (α) are key factors. The results are compared to the uncoupled modal response history analysis (UMRHA) procedure and some existing formulations for a nine story building subjected to the El Centro 1940 ground motion. It appears that the new theoretical approach leads to enough accurate estimation of the inelastic deformation ratio compared to the UMRHA one.

The effect of increasing Cu and Ni on a significant enhancement of mechanical properties of high strength low alloy, low carbon steels of HSLA-100 type

High strength low alloy steels (HSLAs) containing copper, nickel and low amount of Carbon are a new generation of high strength low alloy steels that are widely used in shipbuilding. Strengthening elements such as Cu, Ni, and to some extend C, play a significant role in this family of steels. By increasing the amount of Cu, Ni, and by selection of proper final temperature of rolling, austenitization and aging, it is possible to enhance the yield strength of this steel up to 160 ksi (1102 MPa) while at the same time toughness remains at an acceptable level. In this investigation, the effect of increasing Cu and Ni on mechanical properties of these steels was elaborated. Four steels with varying amounts of Cu and Ni were cast, and hot rolled by a thermomechanical controlled processing. The steels were then austenitized at 920 °C for 45 min followed by quenching in water. Finally, the steels were aged at 650 °C for one hour. Optical microscope, and Filed Emission Scanning Electron Microscope (FE-SEM) were used to study microstructural evolution. Mechanical properties variation was evaluated by tensile and microhardness tests. Results showed that by increasing the amount of these two elements, hardness and tensile strength were increased in thermomechanically controlled processed, austenitized and aged specimens. Yield strength values of the rolled samples were somehow scattered which was due to a slight difference in final rolling temperature and the subsequent rapid cooling. Yield strength under austenitization and quenching conditions increased by increasing the amount of Cu and Ni which could be due to the presence of Nb (C, N) precipitates. Increasing the amount of Cu precipitates after quench could also be another reason for yield strength increment. Increasing the amount of Cu and Ni in samples containing 4.16 and 7.65 wt% for each of these alloys led to the reduction of Ac1 (austenite formation temperature). Selecting aging temperature (650 °C) higher than the austenite formation temperature could probably lead to the growth of the carbides, softening of martensite layers and lower amount of dislocations density hence for the reduction of yield strength of the aged steels. As well, with the addition of the mentioned amounts of Cu and Ni, yield strength of 705 MPa (102.2 ksi), tensile strength of 1072 MPa (155.4 ksi), elongation of 14% and area reduction of 63% were obtained in the aged steels of this investigation.

Characterization of 14YWT oxide dispersion strengthened structural materials under electrically-assisted tension

In this study, we investigated the use of an electrically-assisted (EA) forming process to reduce the forming force of ODS ferritic steels. The effects of a continuous electric current on 14YWT, which is a kind of ODS material, during plastic deformation were evaluated. First, EA uniaxial tension tests show that the electric current is able to reduce the flow stress of 14YWT. 14YWT exhibits a ductility minimum at a current density of 34.5 A/mm2 which is consistent with fractography results. Hardness measurements and TEM results indicate that oxide particles are stable during the EA process. Second, microstructure analysis was performed on the sample in its as-received state and after current treatment. The microstructures are stable when subjected to high current density. Third, a thermal model was developed to predict the Joule heating temperatures. The temperatures were compared with the experimental results. Finally, a temperature-dependent hardening model was used to explore the mechanisms acting during EA deformation. Since the model can accurately predict the yield strength of 14YWT under EA conditions without the incorporation of non-thermal effects, it can be concluded that the reduction in yield strength is due to the Joule heating generated under continuous current loading conditions. An oven-heated pure thermal tension test was conducted to confirm this conclusion. The findings generated from this study will result in the development of innovative manufacturing processes such as the electrically-assisted tube forming processes.