Rolling Direction Research Articles

Comparative study of tensile properties and impact toughness of duplex lightweight steel

Herein, a comparative study regarding the tensile properties and impact toughness of duplex lightweight steel and its deformation behavior was conducted to broaden its application from automotive steel sheets to thick-plate applications at various temperatures using Fe-0.2C–15Mn–6Al and Fe-0.4C–15Mn–6Al hot-rolled steels as model alloys. These steels revealed duplex microstructures with a large fraction of γ austenite (>0.7), featuring elongated δ ferrite grains aligned with the rolling direction and nearly globular γ grains. Both steels demonstrated an exceptional balance of tensile strength and ductility despite their low temperatures ranging from −20 °C to −100 °C, which was attributed to the active dynamic strengthening mechanisms, such as transformation-induced plasticity (TRIP) and twinning-induced plasticity (TWIP). However, contrary to the promising tensile test results, the steels demonstrated low values of the impact absorbed energy at temperatures ranging from −60 °C to −196 °C. This difference was likely owing to the rapid deformation rates in the Charpy impact tests compared to tensile tests, leading to the evolution of significant damage indicated by deep parallel cracks within the δ grains, without significantly activating the TRIP effect. Therefore, despite the impressive low-temperature tensile properties of the duplex lightweight steel, its suitability for cryogenic thick-plate applications must be approached with caution owing to the potential for compromised mechanical properties under sudden impact conditions.

Comparison of Rolling and Transverse Direction Properties of Al/Ti Laminated Metal Composites Prepared by Cold Roll Bonding and Subsequent Annealing

Comparison of Rolling and Transverse Direction Properties of Al/Ti Laminated Metal Composites Prepared by Cold Roll Bonding and Subsequent Annealing

A Novel Approach for Evaluating the Influence of Texture Intensities on the First Magnetization Curve and Hysteresis Loss in Fe-Si Alloys.

This paper examines the relationship between the magnetization behavior and crystal lattice orientations of Fe-Si alloys intended for magnetic applications. A novel approach is introduced to assess anisotropy of the magnetic losses and first magnetization curves. This method links the magnetocrystalline anisotropy energy of single crystal structures to the textures of polycrystalline materials through a vectorial space description of the crystal unit cell, incorporating vectors for external applied field and saturation magnetization. This study provides a preliminary understanding of how texture influences magnetic loss rates and the first magnetization curves. Experimental results from Electron Back-Scattered Diffraction (EBSD) and Single-Sheet Tests (SSTs), combined with energy considerations and mathematical modeling, reveal the following key findings: (i) a higher density of cubic texture components, whether aligned or rotated relative to the rolling direction, decreases magnetic anisotropy, suggesting that optimizing cubic texture can enhance material performance; (ii) at high magnetic fields, there is no straightforward correlation between energy losses and polarization; and (iii) magnetization rates significantly impact magnetization loss rates, highlighting the importance of considering these rates in optimizing Fe-Si sheet manufacturing processes. These findings offer valuable insights for improving the manufacturing and performance of Fe-Si sheets, emphasizing the need for further exploration of texture effects on magnetic behavior.

Study of the comfortable efficiency of the automobile using the seat’s Negative-Stiffness-Structure via two mathematical models

The isolating performance of NSS (Negative-Stiffness-Structure) on ameliorating the automotive’s comfortable in all vertical, pitching, and rolling directions has been not studied yet. Thus, two vibration models of the automobile including the two-dimensional (2-D) model and three-dimensional (3-D) model are built to evaluate automobile’s comfortable efficiency under various conditions. The reduction of the seat and automobile accelerations has been used as an evaluation index. Results present that seat’s vertical acceleration using NSS is evidently improved compared without NSS in two models of the automobile. Especially, the seat’s root-mean-square acceleration with NSS is strongly deteriorated by 65.1% with 2-D model and reduced by 69.7% with 3-D model in comparison without NSS. However, the seat’s NSS does not affect the pitching vibration of the automobile’s body. Besides, from the comparison results between 2-D and 3-D models, seat’s NSS could strongly ameliorate the comfortable efficiency in both vertical and rolling vibrations while the seat’s NSS does not affect improving the automobile’s pitching angle of the automobile. Therefore, to fully assess NSS’s isolating performance as well as improve the comfortable efficiency of the automobile in all vibration directions, 3-D model of the automobile should be used.

Study on Mechanical and Electrical Properties of High Content CNTs/Cu Composites.

It is expected that composites made of carbon nanotubes (CNT) and copper (Cu) display both mechanical and electrical properties, but the low damage dispersion and high-quality composite of high-content CNTs have always been research difficulties. In this paper, high-content CNTs/Cu composites were prepared. The effects of the sintering method, sintering temperature, directional rolling and the CNTs' content on the relative density, hardness and electrical conductivity of the composites were studied. The uniform dispersion of high-content CNTs in Cu matrix was achieved by ball milling, sintering and rolling, and the processes did not cause more damage to the CNTs. The properties of composites prepared by spark plasma sintering (SPS) and vacuum hot pressing sintering (HPS) were compared, and the optimum process parameters of SPS were determined. When the CNTs' content is 2 wt.%, the hardness is 134.9 HBW, which is still 2.3 times that of pure Cu, and the conductivity is the highest, reaching 78.4%IACS. This study provides an important reference for the high-quality preparation and performance evaluation of high-content CNTs/Cu composites.

Shear behavior of Cu/Al/Cu trilayered composites prepared by high-temperature oxygen-free rolling

The interfacial microstructure, interfacial shear properties, and shear fracture morphology of Cu/Al/Cu trilayered composites prepared by high-temperature oxygen-free rolling were studied, and the interfacial shear fracture mechanism was revealed. The results showed that the Cu/Al/Cu trilayered composites have a good metallurgical bonding interface. The interfacial microstructure is composed of Al2Cu, AlCu, and Al4Cu9. The intermetallics (IMCs) parallel to the rolling direction show discontinuous distribution, while the IMCs perpendicular to the rolling direction have mainly continuous distribution and occasional discontinuous distribution. The interfacial shear strength at room temperature can reach 68 MPa, and when the test temperature rises to 350 °C, the interfacial shear strength drops sharply to 16.9 MPa. The interfacial shear fracture mainly occurs in the low-strength Al layer due to the good metallurgical bonding interface. The IMCs near the shear fracture exhibit clear signs of cracking, and there is a phenomenon where the Cu layer embeds into the Al layer in a "sawtooth" shape. Meanwhile, shear fracture also occurs in the IMCs layer, and a small amount of Al will attach to the surface of the IMCs. However, the high bonding strength resulting from the excellent metallurgical bonding of the interface makes this type of shear fracture rare. The shear fracture of Cu/Al/Cu trilayered composites is mainly dominated by the fracture of the low-strength Al layer and the occasional fracture of the IMCs.

On the anisotropic fracture behaviour of AA2050-T84 thick plate

Anisotropy in the fracture behaviour of AA2050-T84 was investigated using 2D digital image correlation (DIC)-assisted 3-point bending fracture toughness test on specimens with crack propagation direction oriented along the normal direction (ND) and rolling direction (RD). The tensile properties along the RD indicated slightly higher yield strength (482 ± 8 MPa) than ND sample (469 ± 9 MPa), while the fracture toughness in terms of energy release rate was higher when the notch was oriented along the ND (35.3 ± 1 kJ/m2) compared to the RD (18.5 ± 0.9 kJ/m2). Fractography of the fractured surfaces and detailed electron backscatter diffraction (EBSD) analysis of the microstructure along crack paths unveiled higher crack tortuosity with extensive secondary cracking in the TD-ND specimen than in the TD-RD. DIC measurements clearly showed a larger deformation zone for the TD-ND specimen also as which corroborated the plastic zone size determined using linear elastic fracture mechanics (LEFM). Additionally, the crystallographic model of tilt and twist angle differences between the neighbouring grains was employed to explain the increase in crack path tortuosity and higher dissipation of plastic work contributing to superior fracture toughness for the TD-ND sample.

Elucidating the effect of whiskers on microstructural, mechanical and wear properties of ceramic-metal composites for sports venues applications

Ceramic whiskers reinforced composites are widely used in electrical, medical, and constructional applications due to their desirable strengths, hardness, and wear characteristics. In this study, to examine the wear and friction characteristics, the pressureless infiltrated Cu–SiC composites with different content of SiC whiskers were roll bonded to Al layer. According to SEM images, the SiC whiskers were distributed across the microstructure although they were aligned along rolling direction. Incorporation of SiC whiskers to Cu matrix led to rise of composites’ strengths, young moduli, and hardness values. The measured values of Al and Cu–SiC layers increased from 50 HV to 135 HV in Al/Cu–SiC (5 wt%) to 57 HV and 159 HV in Al/Cu–SiC (15 wt%). Ductile type of fracture along with dimples, delamination, and debonding of whiskers appeared on fracture surfaces. However, more debonding of SiC whiskers was observed as SiC content increased. Accordingly, mass loss decreased and less adhesive wear mechanism was observed. The mass loss decreased from 6.3 mg in Al/Cu–SiC (5 wt%) to 5.2 mg in Al/Cu–SiC (15 wt%).

Analysis of the Anisotropic Cyclic Material Behavior of EN AW-1050A H24 Derived from Strain-Controlled Testing Using a Clip-On Extensometer and an Optical System

Due to its good conductive properties, unalloyed (pure) aluminum, such as EN AW-1050A H24, finds new fields of application in electromobility. To optimize components, the cyclic material behavior must be understood and described precisely as a foundation of a proper fatigue life estimation. Various cyclic tests were performed to not only derive the cyclic parameters to describe the material but also to find the most suitable procedure to deal with the challenges faced during the experiments. The main point of interest is the comparison between a surface-mounted clip-on extensometer and an optical system both used for strain control in cyclic tests. For the analysis of the anisotropic behavior of EN AW-1050A H24, un-notched flat specimens were extracted from sheet metal lengthways and crossways in respect to the rolling direction. While the cyclic material behavior for specimens of both directions of extraction is characterized by cyclic softening in general, the specimens extracted crossways show a strain-amplitude-dependent cyclic softening with strong strain localization especially at the contact points of the knives of the clip-on extensometer leading to an increased quantity of invalid experiments as well as sudden fractures. In the study, it was possible to show the benefits of a contactless optical strain control system when dealing with very soft metallic materials such as EN AW-1050A H24.

Constitutive description of distortional hardening in a TWIP steel: Addressing differential hardening under nonlinear strain paths

The present study aims to describe the in-plane differential hardening behaviour of the twinning induced plasticity sheet metal TWIP980 under various stress states, including uniaxial tension, plane strain tension, and pure shear, particularly focusing on non-proportional loading conditions. The true stress–strain curves for each stress states were inversely obtained from their corresponding load–displacement curves and modeled using a differential hardening model that can accommodate all three stress states simultaneously on plastic work (density) contours. For non-proportional loading tests, oversize specimens were initially stretched under uniaxial tension up to a 10% pre-strain along the rolling, diagonal, and transverse directions, respectively. Subsequently, the three stress states were applied to subsize specimens cut from the deformed oversize specimens along the rolling direction. To describe the hardening behaviours during non-proportional loading, a homogeneous anisotropic hardening model was adopted and calibrated using two-step uniaxial tension tests. Subsequently, the differential hardening model was successfully incorporated into the homogeneous anisotropic hardening model to describe both the differential hardening and the strain path change-induced hardening behaviours under the two-step loadings, i.e., uniaxial tension to pure shear and uniaxial tension to plane strain tension. Both experimental and simulation results underscore the necessity to consider differential hardening under non-proportional loading conditions.

The Action Mechanism of Rolling Texture on the Anisotropic Behavior of a Pure Titanium Plate

This work combined theoretical calculation with experimental characterization to methodically study the anisotropy mechanism and evolution of the plastic behavior of pure titanium. Initially, a constant-strain uniaxial tensile test was used to measure the anisotropy of the yield behavior along the rolling direction (RD) and transverse direction (TD). Subsequently, the information of crystal orientation both before and after deformation was statistically characterized using electron backscatter diffraction (EBSD). Ultimately, the main deformation mechanism was determined by combining Schmid law with an analysis of the variation of SF values of each deformation mode with the angular relationship between the loading axis and the grain’s c-axis. The findings demonstrate that, for each slip system, the variation trend and value of the SF are influenced by the angle formed by the loading axis and the grain’s c- and a-axes. The primary result of dislocation slip activation is the change of the tilt angle of the grain c-axis from ND to TD, but this has little effect on the tilt angle of the grain c-axis from ND to RD. Prismatic <a> slip dominates the tensile deformation along the RD. Pyramidal <a> slip and pyramidal <c+a> slip will be activated during the subsequent hardening, whereas basal <a> slip is difficult to activate. The prismatic <a> slip in the soft-oriented grain will be preferentially activated during the tensile deformation along the TD, and the prismatic <a> slip and pyramidal <a> slip will become the dominant deformation modes during the subsequent hardening. Some soft-oriented grains could activate basal <a> slip and pyramidal <c+a> slip, but dislocation slip is restricted and coordinated by {10-12}ET.

Finite Element Simulation of Multi-Pass Rolling of a Pure Aluminum Target under Different Rolling Routes and Methods

By coordinating the rolling direction and mode, a multi-rolling plastic deformation process for an aluminum (Al) sputter target is proposed to achieve multiple excellent properties, including a uniform and fine grain structure and low defect risk, which are significant in producing high-quality sputtered films. In this work, therefore, DEFORM 3D 10.2 software is adopted to establish three strategies, clock-synchronous rolling, cross-synchronous rolling, and clock–snake rolling. The effect of different rolling routes and modes on the metal flow velocity (MFV), effective strain distribution (ESD), grain size distribution (GSD), damage, and rolling force (RF) are comparatively investigated. The simulation results show that clock–snake rolling can increase the MFV and effective strain by producing a deeper deformation than the others. It provides sufficient energy for dynamic recrystallization to promote grain refinement. In combination with the microstructure homogeneity promoted by the clock rolling route, the GSD from 6.5 to 44.3 μm accounts for about 80.5% of all the grains because of the fact that a randomly oriented grain region is full of high-angle grain boundaries. Compared with the synchronous rolling mode, the decrement in RF maximum reaches up to 51% during the asynchronous rolling process because component energy is consumed to form cross-sheering stress. It remarkably reduces the risk of defects, with a damage value of less than 73%, and simultaneously improves energy efficiency owing to smaller and uniform grains caused by less RF. The results obtained in this work are of great significance as they can guide practical production in the metal target industry.

Visually induced vertical vergence as a motion processing biomarker associated with postural instability

The present study explored visually induced vertical vergence (VIVV) as non-specific motion processing response. Healthy participants (7 male, mean age 28.57 ± 2.30; 9 female, mean age 27.67 ± 3.65) were exposed to optokinetic stimuli in an HTC VIVE virtual reality headset while VIVV, pupil-size, and postural sway was recorded. The methodology was shown to produce VIVV in the roll plane at 30 deg/s. Subsequent trials consisted of 40 s optokinetic motion in yaw, pitch, and roll directions at 60 deg/s, and radial optic flow; optokinetic directions were inverted after 20 s of motion. Median VIVV amplitude changes were normalized to the clockwise roll rotation, analysed, and correlated with changes in pupil-size and body sway. VIVV, pupil-size, and body sway were all affected by changes in optokinetic direction. Post-hoc analyses showed significant VIVV responses during optokinetic yaw and pitch rotations, as well as during radial optic flow stimulations. VIVV magnitudes were universally correlated with pupil-size and body sway. In conclusion, VIVV was expressed in all tested dimensions and may consequently serve as a visual motion processing biomarker. Failing to support binocularity while responding to optokinetic directionality, VIVV may reflect an eye-movement response associated with increased postural instability and stress, similar to a dorsal light reflex.

Low-cost Ti-6Al-4V containing low content nano-carbon solid solution for achieving high strength and good ductility

With the rapid advancement of the aerospace industry, in addition to higher requirements for material properties, the cost-effective of its production have also attracted more attention. In this work, titanium matrix composite with high performance and low cost was designed using ball milling, spark plasma sintering and hot rolling process, i.e. hydrogenated dehydrogenated Ti and AlV powders as the precursor of Ti-6Al-4 V matrix, and a low content (0.15 wt%) reduced graphene oxide (rGO) with high-activity was selected to reinforce the matrix alloy. The as-rolled composite shows obvious texture orientation along the rolling direction without pores and microcracks. The incorporation of rGO led to the activation of the as-rolled composites along the {0001}[112¯0] type base slip. The as-rolled composite containing only 0.15 wt% rGO exhibits superior yield strength (1308.1 MPa) and ultimate tensile strength (1444.3 MPa), which are 11% and 9.3% higher than those of the matrix alloy, respectively, and the elongation remains at ∼5.6%. The strengthening mechanisms are mainly attributed to the solid solution strengthening effect of interstitial carbon in the matrix after the incorporation of rGO. This work highlights the development potential of low-cost and high-strength titanium matrix composites

Microstructure and texture evolution in cold-rolled W during annealing

The tungsten(W) was prepared by cold isostatic pressing and sintering, and its characteristics were further enhanced by cold rolling in this paper. The microstructure and textural evolution of cold-rolled and annealed W were primarily studied, and the slip system and dislocations were also deeply researched. The study reveals that grain boundaries in cold-rolled W and samples annealed at 1200 K have small angles of misorientation and high kernel average misorientation (KAM) values, while samples annealed at 1500 K and 1800 K have high angles of misorientation and low KAM values. Low angle grain boundaries (GBs) promote dislocation transfer and improve ductility. After 1800 K annealing, W becomes nearly-equiaxed polyhedrons, with γ-fiber texture dominating. The rolling direction (RD) is better suited for plastic deformation than the transverse direction (TD), but plasticity deteriorates due to changes in microstructure.

Deformation Behavior of AZ31 Magnesium Alloy with Pre-Twins under Biaxial Tension.

In the present study, the mechanical response and deformation behavior of a Mg AZ31 plate with different types of pre-twins was systematically investigated under biaxial tension along the normal direction (ND) and transverse direction (TD) with different stress ratios. The results show that significant hardening was observed under biaxial tension. The yield values in the direction of larger stress values were higher than those under uniaxial loading conditions, and the solute atom segregation at twin boundaries generates more obvious strengthening effect. Noting that, for TRH (with cross compression along the rolling direction (RD) and TD and annealing at 180 °C for about 0.5 h) sample, the strength effect of the RD yield stress σRD:σND = 2:1 was higher than that of the ND yield stress under stress ratio σRD:σND = 1:2. There is a complex competition between twinning and detwinning under biaxal tension along the ND and TD of the pre-twinned samples with the variation in the stress ratio along the TD and RD. The variation in the twin volume fractions for all samples under biaxial firstly decreases and then increases with a higher stress ratio along the ND. As for the TDH sample (precompression along the TD and annealing), the changes of the twin volume fraction were lower than that of the TR sample (cross compression along the TD and RD). However, the amplitude of variation in twin volume fraction of the TRH sample is higher than that of the TR sample. This is because the relative activity of detwinning decreases and that of twinning increases, as the ND stress mainly leads to the growth of pre-twins and the TD stress often promotes detwinning of primary twins. With a higher stress ratio along the ND, the activity of twinning deformation increases and that of detwinning decreases.

Effect of strain path and short-term post-annealing on the microstructure, texture, and mechanical anisotropy of low-carbon steel

In this research, the effect of strain path and short-term post-annealing on the microstructure, texture, and mechanical anisotropy of low-carbon steel was investigated. Asymmetric unidirectional rolling (AUR) and asymmetric cross rolling (ACR) were applied on Fe-0.072C steel. The ACR-processed sheet revealed a very limited number of new grains compared to the AUR-processed sheet, which was due to the dynamic recovery induced by strain path change. The average ferrite grain size of the post-annealed AUR- and ACR-processed samples was 11.5 and 14.1 μm, respectively. The dominant recrystallization in the annealed AUR-processed sheet was discontinuous static recrystallization, while that in the annealed ACR-processed sheet was continuous static recrystallization. The weak typical rolling textures (γ-fiber and α-fiber) at the midthickness of both rolled sheets demonstrated that the shear deformation effectively contributed to the formation of the shear textures during asymmetric cold rolling. The ACR decreased the intensity of the overall texture more than the AUR process due to the changes in the reference frame of deformation after each pass, which destabilized ideal texture components. The results showed that Goss and {111}〈112〉 components were continuous and discontinuous static recrystallization textures in the asymmetrically cold-rolled low-carbon steel sheet during the annealing treatment, respectively. The annealed AUR-processed sheet revealed a weaker texture as compared to the annealed ACR-processed sheet. The significant changes in the preferred orientations of the annealed AUR-processed sample led to weaker texture intensity compared to the annealed ACR-processed sheet. The hardness of the annealed AUR-processed sheet (183.8 HV) was higher than that of the annealed ACR-processed steel (156.9 HV), which was owing to the larger grain size and also the elimination of the γ-fiber texture in the annealed ACR-processed sheet. The strength along the rolling direction was lower than that along the transverse direction in the AUR-processed sheet. However, in the ACR-processed sheet, the values of strength were similar along three different tensile directions. As an important conclusion, if both high-strength and low-anisotropy are needed in the low-carbon steel sheets, it's better to apply ACR rather than AUR. In addition, if both high toughness and low anisotropy are essential, it's better to use AUR followed by post-annealing rather than ACR + post-annealing. The length of the intermediate stage of work hardening in the annealed ACR-processed sample was much less than the annealed AUR-processed sheet due to the presence of harder orientations (〈111〉 and 〈110〉) along rolling and transverse directions in the annealed ACR-processed sample. Finally, the fracture behavior of deformed and post-annealed steel sheets for both strain paths was ductile and shear ductile.

Anisotropy of Electrical and Thermal Conductivity in High-Density Graphite Foils.

Flexible graphite foils with varying thicknesses (S = 282 ± 5 μm, M = 494 ± 7 μm, L = 746 ± 8 μm) and an initial density of 0.70 g/cm3 were obtained using the nitrate method. The specific electrical and thermal conductivity of these foils were investigated. As the density increased from 0.70 g/cm3 to 1.75 g/cm3, the specific electrical conductivity increased from 69 to 192 kS/m and the thermal conductivity increased from 109 to 326 W/(m·K) due to the rolling of graphite foils. The study showed that conductivity and anisotropy depend on the shape, orientation, and contact area of thermally expanded graphite (TEG) mesoparticles (mesostructural factor), and the crystal structure of nanocrystallites (nanostructural factor). A proposed mesostructural model explained these increases, with denser foils showing elongated, narrowed TEG particles and larger contact areas, confirmed by electron microscopy results. For graphite foils 200 and 750 μm thick, increased density led to a larger coherent scattering region, likely due to the rotation of graphite mesoparticles under mechanical action, while thinner foils (<200 μm) with densities > 1.7 g/cm3 showed increased plastic deformation, indicated by a sharp reduction in the coherent scattering region size. This was also evident from the decrease in misorientation angles with increasing density. Rolling reduced nanocrystallite misorientation angles along the rolling direction compared to the transverse direction (TD) (for 1.75 g/cm3 density ΔMA = 1.2° (S), 2.6° (M), and 2.4° (L)), explaining the observed anisotropy in the electrical and mechanical properties of the rolled graphite foils. X-ray analysis confirmed the preferred nanocrystallite orientation and anisotropy coefficients (A) using Kearns parameters, which aligned well with experimental measurements (for L series foils calculated as: A0.70 = 1.05, A1.30 = 1.10, and A1.75 = 1.16). These calculated values corresponded well with the experimental measurements of specific electrical conductivity, where the anisotropy coefficient changed from 1.00 to 1.16 and mechanical properties varied from 0.98 to 1.13.

Electropulsing anisotropy of cold-rolled Grade 2 titanium sheet: Effect of electric current direction on recrystallization and hardness

This study investigated the effects of electropulsing treatment (EPT) condition on the microstructure and microhardness of cold-rolled Grade 2 Ti sheet. Particular attention was paid to the dependence of the material properties on the electric current direction, referred to as electropulsing anisotropy. Direct-current (DC) EPT was applied along either the rolling direction (RD) or transverse direction (TD) of the rolled sheet. EPT along the TD resulted in a higher heating rate and maximum temperature, whereas that along the RD accelerated the static recrystallization (SRX) process under identical electropulsing parameters. Such a discrepancy was interpreted using the elongated grain structure and basal texture in the cold-rolled Ti sheet. These results were further supported by microhardness measurements, confirming the presence of electropulsing anisotropy during DC EPT in Ti alloys for the first time. In addition, the employed EPT was compared to a traditional furnace heat treatment (FHT) with rigorous temperature and time control, wherein the optimum EPT process spent only 13% of the processing time to complete SRX with a lower thermal energy requirement. This indicates a significant athermal contribution of EPT to electropulsing anisotropy.

Research on deformation behaviors at different temperatures of lean duplex stainless steel S32101 produced by direct cold rolling process

In this paper, the mechanical properties, work hardening characteristics and deformation mechanism of lean duplex stainless steel (LDSS) S32101 produced by direct cold rolling were studied under different temperature conditions. The yield strength (YS) and tensile strength (TS) of S32101 decreased with the increase of deformation temperature, while the elongation increased first and then decreased. The TS of S32101 at −70 °C was 1052.6 MPa, the elongation remained 57.2%, and the product of strength and elongation (PSE) was as high as 60.2 GPa·%, which was mainly due to the synergistic strengthening of transformation induced plasticity (TRIP) and twinning-induced plasticity (TWIP) effects in austenite at cryogenic temperatures. The efficiency of grain refinement at cryogenic temperature was improved by TRIP effect and deformation twins (DTs), indicating that it had the potential to be applied at low temperature (−70 ∼ −30°C). Moreover, the high density nanotwins and the strong interaction between the dislocation and nanotwin bundles also contributed to strain hardening at low temperatures and thus better comprehensive mechanical properties could be achieved.