Effect Of Rolling Direction Research Articles

The effect of rolling direction and strain rates on the tensile properties of AA2024-T3 aluminum alloy

The AA2024-T3 alloy is a lightweight and durable material commonly used in the aerospace industry. This study investigates the impact of the rolling direction (RD) and strain rates on the alloy’s tensile properties. Tensile tests have been performed on samples oriented parallel and transverse to the rolling direction at varying strain rates (5, 25, and 125 mm/min). Samples parallel to the rolling direction have exhibited higher strength compared to those in the transverse direction (TD). At a strain rate of 5 mm/min, the maximum tensile strength in RD samples has been 530.72 MPa, while in TD samples, it has been 505.76 MPa. At 25 mm/min, the tensile strength has been 498.31 MPa in RD and 482.91 MPa in TD. At 125 mm/min, the tensile strength has been 508.52 MPa in RD and 480.36 MPa in TD. The increase in strain rate has had a complex effect on the mechanical properties. The total elongation values have also varied with strain rate, with the highest total elongation observed at 5 mm/min (0.168) in both RD and TD directions. These findings have highlighted the significant impact of the rolling direction and strain rate on the mechanical properties of the AA2024-T3 alloy, which should be considered in design and manufacturing processes.

Experimental Investigation on the Formability of Al-Mg Alloy 5052 Sheet by Tensile and Cupping Test.

Aiming at the enhancement of the lightweight formability potential of aluminum alloy, the bulging and tensile properties of a 5052 Aluminum alloy sheet were tested on a microcomputer controlled sheet metal forming tester and tensile testing machine. The effects of different blank holder force, punch velocity and lubrication conditions were investigated on bulging properties by the experimental analysis. The cupping values (Erichsen Cupping Index: IE) of sheets with a thickness of 1.2 mm at room temperature were obtained under different process parameters. Meanwhile, the anisotropic property of the material was analyzed in different rolling directions. The results show that the sheet cupping values increase with the increase of blank holder force and punch velocity, and the stress state was changed due to the changing of the blank holder force and strain rate. Moreover, the use of lubricating conditions with a lower coefficient of friction allows the sheet to exhibit a larger cupping value. The effect of rolling direction on the anisotropy of 5052 aluminum alloy sheet is distinct, which means in the aluminum alloy sheet forming process the anisotropy factor should be carefully considered.

Influence of hot rolling on friction and wear behaviour of Al6061-ZrB2 in-situ metal matrix composites

The Al6061-ZrB2 metal matrix composites were prepared by stir-casting approach via in-situ reaction, using aluminium master alloys comprising 3% Boron and 10% Zirconium. Developed in-situ composites were rolled at a temperature of 400 °C. Both the as-cast and hot-rolled alloys and their in-situ composites were studied for microstructure, friction, and wear properties. The effects of rolling Direction (RD), Transverse Direction (TD), and 45° to rolling directions on the friction and wear behaviour of in-situ MMCs were evaluated. With the addition of ZrB2 particles, the composites demonstrated increased wear resistance and a decreased friction coefficient. In comparison to samples tested in the transverse direction, samples tested in the RD and 45D orientations had the lowest coefficients of friction and wear rates (TD).

Effect of rolling direction and hydrogen on fatigue properties in cold-rolled stainless steels

Effect of rolling direction and hydrogen on fatigue properties in cold-rolled stainless steels

Study on high temperature creep behavior of the accident-resistant cladding Fe–13Cr–4Al-1.85Mo-0.85Nb alloy

The Fe–13Cr–4Al-1.85Mo-0.85Nb alloy, as accident-resistant fuel cladding material in light water reactor (LWR), was prepared by a vacuum induction melting, forging and hot rolling process. In this study, the creep behaviors of the alloy at the temperature range of 400–450 °C were studied. The effects of rolling direction (RD), transverse direction (TD), creep temperatures and stresses on the creep properties were systematically investigated. The results show that the steady-state creep rates of the FeCrAl alloy increase with the increase of the loaded stress, which vary in the range of 8.81 × 10 −10 s −1 to 8.40 × 10 −8 s −1 in the RD and 8.30 × 10 −9 s −1 to 5.17 × 10 −7 s −1 in the TD. Based on the analysis of the real stress exponent n equaling to 5.0, the creep processes in the both RD and TD are controlled by dislocation climbing mechanism, as evidenced by the microstructure of dislocations tangled with precipitations after creep test. At 540 MPa and the temperatures of 400–450 °C, the creep activation energies in the RD and TD are 421.06 kJ mol −1 and 424.7 kJ mol −1 respectively. Before creep test, the dispersion of fine Mo-, Nb-, and Si-rich Laves phases is observed. After creep test, ‘spheroidization’ of these secondary Laves phases obviously occurs. EBSD analysis shows that the grains in the TD are smaller and equiaxed, while the grains in the RD are large and deformed. This is one of the reasons on the big differences of the creep rate of the alloy in the TD comparing with the RD. The average geometrically necessary dislocations (GNDs) of the cross-sectional structure of the alloy decrease after creep test in both the RD and TD. Moreover, the creep rate in the RD is about 1/10 of that in the TD, mainly due to the large elongated grains with less grain boundaries and higher GNDs in the RD. The obtained conclusions provide researchers and engineers with useful references for the engineering application of the FeCrAl alloy as accident-resistant fuel cladding material. • Creep process of the FeCrAl alloy is controlled by dislocation climbing mechanism. • Creep properties and reasons on anisotropy of creep rates of the alloy are revealed. • The creep rates of the alloy in the RD is around 1/10 of that in the TD. • GNDs of the cross-sectional structure of the alloy decrease during the creep process. • Creep activation energies in the RD and TD are 421.06 and 424.7 kJ mol −1 respectively.

The effect of rolling direction and strain rate on the tensile properties of DP450 and DP800 steels used in the automotive industry

Çift fazlı DP (Dual Fazlı) çelikleri otomotiv sanayinde en çok tercih edilen çelik gruplarındandır. Kullanımları sırasında bu çeliklerin yükleme yönüne göre hadde yönü ve deformasyon hızı son derece önem arz etmektedir. Bu çalışmada, DP450 ve DP800 çift fazlı çeliklerinde deformasyon hızı ve haddeleme yönüne bağlı olarak çekme sonuçları incelenmiştir. Deneysel çalışmalarda, haddeleme yönünün çekme ekseniyle yaptığı açılar 0°, 45° ve 90°, deformasyon hızları 2.4x10-4, 2.4x10-3, 2.4x10-2 ve 1.2x10-1 s-1 olarak belirlenmiştir. Çalışmada elde edilen sonuçlar göstermiştir ki, DP450 ve DP800 çeliklerinde deformasyon hızının çekme özellikleri üzerindeki etkisi hadde yönü etkisinden daha fazla olmuştur. Her iki çelikte de deformasyon hızı artışı ile akma ve çekme mukavemeti değerleri artmış, kopma uzaması değerleri ise önemli ölçüde düşmüştür. Ayrıca, her iki çelikte de deformasyon hızının akma mukavemeti üzerindeki etkisi çekme mukavemeti üzerindeki etkisinden daha fazla olmuştur. DP800 çeliğinde deformasyon hızı ile mukavemet artış oranı DP450 çeliğine nazaran daha düşük kalırken, kopma uzaması düşüş oranı ise daha fazla olmuştur. Hadde yönünün etkisine bakıldığında ise, DP450 ve DP800 çeliklerinde 45° hadde yönünde nispeten daha yüksek mukavemet değerleri gözlenirken aynı hadde yönünde daha düşük uzama değerleri elde edilmiştir.

Effect of rolling direction on microstructure evolution of CL60 wheel steel

The effect of rolling direction on the microstructure evolution of CL60 wheel steel was systematically studied using a rolling-sliding wear testing apparatus. The evolution of microstructures in depth and on the sub-surface was investigated using Electron Backscatter Diffraction (EBSD) and scanning electron microscopy (SEM). The results indicated that the microstructure in depth underwent a transition from the sub-boundaries introduced at low strain into grains with large-angle grain boundaries (LAGBs), leading to a full ultra-fine grain (UFG) microstructure at a large strain. Notably, an abnormal growth of the strain-induced UFGs near the surface occurred at the beginning of the rolling direction reversal (RDR). Meanwhile, the microstructure of the surface layer was changed from a fiber structure parallel to the surface under the unidirectional rolling of wheel materials to a wave structure. With the increase in the number of cycles after the RDR, the grain orientation on the sub-surface was changed from {111} to {101} and finally to a random orientation, resulting in a completely reversed plastic deformation layer. Additionally, the number of cycles per reversal and the total number of cycles also played an important role in microstructure evolution.

DETERMINATION OF MATERIAL RESPONSE AND OPTIMIZATION OF JOHNSON-COOK DAMAGE PARAMETERS OF ALUMINIUM 7075 ALLOY

The effects of rolling direction and notch radius on the mechanical response of aluminium 7075-T651 alloy were investigated and the Johnson-Cook damage parameters of aluminium 7075-T651 alloy on both rolling directions were determined. Specifically, mechanical responses of aluminium 7075-T651 along the rolling direction and perpendicular to the rolling direction were obtained from monotonic tensile tests. 56 tensile tests in total were performed on notched specimens with 3 different notch radiuses and smooth specimens. Tensile tests were repeated 7 times for each case to ensure the consistency and to obtain the closest mechanical response to the real mechanical response with minimum error. Experimental findings revealed that being perpendicular to the rolling direction deteriorates the elongation at failure dramatically but can increase the mechanical properties in elastic region. The final areas of the fractured samples, used for the calculation of Johnson-Cook damage parameters, were measured by an optical microscope. The Johnson-Cook damage parameters of aluminium 7075-T651 alloy for different applications were computed by Levenberg-Marquardt optimization method. Collectively, this study opens the venue for accurate damage simulations of aluminium 7075-T651 along the rolling direction and perpendicular to the rolling direction for different applications.

The effect of rolling direction on the weld structure and mechanical properties of DP 1000 steel

Since gas metal arc welding (GMAW) is a common procedure to join different sheets in the industry, the welding direction dependence on the rolling direction was investigated for a welded DP1000, a ...

An experimental study on the springback in bending of w-shaped micro sheet-metal parts

In sheet-metal bending, defects relating to the component-forms such as springback are common. This is due to the elastic deflection that occurs in the material after the bending process takes place. The objective of the research is to study on the springback behaviour in micro sheet-metal parts. This paper reports an investigation concerning the influence of the material rolling direction on springback in the case of w-shaped bending parts. Micro bending parts using 316 L annealed stainless steel strips having thickness of 50 μm, 75 μm and 100 μm respectively were formed. The tensile and bending behaviours of the parts were observed through the experiment by considering the effect of rolling direction and size-effect related errors. The results revealed that various parameters influence the springback, such as thickness of the sheet, force applied, material rolling-direction and holding time during the sheet-deformation. The scale of the springback was also observed to be random among the parts made with a same sheet material.

Effect of rolling direction on the development of microstructure, texture, and mechanical properties of AZ31B alloys

In the present work, the development of the microstructure, texture, and mechanical properties of AZ31B Mg alloys after rolling at 200°C along different directions was studied. The development of microstructure after rolling can be explained on the basis of twinning and dynamic recrystallization. After the heat-treatment at 300°C in rolled sheets in order to relieve stress, grains in the shear like deformed band developed inhomogeneously like a cluster. The basal planes split and were rotated in the rolling direction (RD). Two samples had similar grain morphologies and textures; nevertheless, these sheets had different mechanical properties. The reasons can be attributed to the influence of the developed microstructure, such as twinning and textures.

An Experimental Study on Bending Process of AISI 304 Steel Sheets by using Diode Laser Forming

Laser bending is a promising technique utilised in order to deform metal sheets that offers the advantage of requiring no hard tooling and no external forces, thus reducing cost and increasing flexibility. Laser forming involves a complex interaction of many process parameters, ranging from those connected with the irradiation of the laser beam to those regarding the thermal and mechanical properties of the workpiece material. The present work is focused on the laser bending of AISI 304 steel sheets by using of a diode laser. The influence of process parameters, such as the power of laser beam and the scanning speed as well as the metal sheet thickness on the bending angle has been taken into account. The investigation has also analysed the effect of rolling direction of the metal sheets and the conditions of cooling on the bending process.

Effect of Rolling Direction to the Strength of a Thin-Walled Steel SHS Beam under Concentrated-Compressive Load and Bending Moment

In this research, it has been carried out the development of a strength analytical method of a thin-walled steel square pipe (Square Hollow Section/SHS) affected by the interaction of concentrated-compressive load and bending moment then it verified by experimental approach. The experimental approach was consisted of measuring a basic material property and the strength of the investigated SHS pipe. The basic material property identified parallel to rolling direction (0o) and perpendicular to rolling direction (90o). The analytical data obtained from cut-off strength method is generally scattered within the acceptable limits of ± 20 % and tends to be in unconservative region. The actual data measured from experiments shows that SHS beam with t = 0.6 mm and longitudinal axis parallel to the rolling direction of base material has higher strength compared to the one of the SHS beam with t= 0.6 mm and longitudinal axis perpendicular to the rolling direction, meanwhile the SHS beam with t= 1.2 mm is tends to be equal. This means that the rolling direction of base material can be considered to be a parameter in the strength design of a thin-walled SHS beam

Influence of Grain Size and Rolling Direction on Stress Measurement by Ultrasonic Surface Wave (Part 2)

Stress measurement based on the change of ultrasonic surface wave has been accepted to find out residual or existing stress on material. This paper shows the effect of rolling direction and grain size of material on surface wave velocity and energy attenuation. Different grain and rolling direction of material type SS 400, S420 and A516 were selected to test its effect. Three grain sizes of each material were varied by normalizing process at three temperature range (no heating, 850°C, 980°C and 1160°C). Through transmission ultrasonic surface wave, frequencies 2.25 and 5 MHz, were applied and recorded the velocity and attenuation of the response. The results show that rolling direction and grain size slightly effect on attenuation of ultrasonic wave but unaffected on sound velocity. Its outcome was compared with the effect of the material coating.

The effect of rolling direction on the creep process of Al–Cu bimetallic sheet

The study of the mechanical properties of aluminium–copper (Al–Cu) metal layered composite, formed by joining aluminium and copper sheets in the process of rolling have been presented in this paper. The influence of the rolling direction on the basic strength parameters and rheological properties of the composite was analysed. All tests were carried out on flat specimens cut from a sheet in the direction compatible with the rolling direction (RD) and transverse direction (TD). Preliminary tests of monotonic uniaxial tension at a temperature of 293K were carried out and the basic mechanical properties of Al–Cu bimetal were determined. The hardening process of the material was described by the three-parameter Swift’s equation. The essential creep tests were carried out at a temperature of 523K in the range of stress 88.5–137.9MPa. The relation between minimum creep rate and applied stress for the specimens cut from the RD and TD directions were determined. The relationships between the time to fracture, stress, and rupture elongation, obtained from the creep tests, were determined as well. Variations of the steady creep rate with time to fracture by using the Monkman–Grant’s model and its modifications were analysed. It was found that the rolling process strongly affected the short-time monotonic deformation at 293K and the creep process at 523K temperature.

Effect of Rolling Direction and Annealing Temperature on Mechanical Properties of Thin Stainless Steel Sheets

Thin stainless steel sheet has been widely used for the small sized and high strength mechanical parts. The materials are initially experienced either the TA (Tension Annealing) or heat treatment after cold rolling, then processed for the final products. Not only stainless steel but thin sheet materials basically have anisotropy in their physical and mechanical properties because of unidirectional rolling history. A few results were reported on the effect of the annealing temperature on those properties. In this paper, the effect of temperature annealing in the air on the anisotropy of mechanical properties of stainless steel thin sheet such as surface roughness, W-bending, Vickers hardness, Young's modulus, spring bending elastic limit and pulley-bendingtype fatigue limit were described.

銅膜材の屈折疲労き裂伝ぱ挙動に及ぼす圧延方向の影響 : 混合モード膜疲労試験とき裂に沿う不連続変位分布計測に基づいて

銅膜材の屈折疲労き裂伝ぱ挙動に及ぼす圧延方向の影響 : 混合モード膜疲労試験とき裂に沿う不連続変位分布計測に基づいて

Filiform corrosion attack on pretreated aluminum alloy with tailored surface of epoxy coating

In the study, on the basis of material analysis of 6016 aluminum alloy widely used in Europe automotive industry, the influences of surface pretreatment on filiform corrosion and adhesion of epoxy coating/aluminum alloy interface were investigated, and the effect of rolling direction and coating property on filiform corrosion was also examined. The alloy surfaces were pretreated with etching solution, and then, respectively, with Aminopropyl silane solution, Aminopropyl phosphonate solution, and hexamethyldisiloxane plasma.The results showed that the susceptibility of pretreated surface to filiform corrosion was basically consistent with the distribution of intermetallic particles, and that water permeation and the tensility of coating were necessary for filament to grow. HMDSO plasma pretreatment could not only efficiently cover the matrix of 6016 aluminum alloy and cathodic intermetallic particles containing Al, Si, Mn, and Fe, but also apparently promote the adhesion of epoxy coating/aluminum alloy, as a result, the specimens with plasma pretreatment exhibited the superior performance in the filiform corrosion and peeling tests, so it was suitable to apply for the pretreatment of aluminum alloy in automotive industry.

Effect of Rolling Direction on the Microstructure and Mechanical Properties of Accumulative Roll Bonding (ARB) Processed Commercially Pure 1050 Aluminum Alloy

The cross-ARB (C-ARB) process, which adopts cross rolling of the two stacked plates, has been performed up to seven cycles on a commercial purity 1050 aluminum alloy to obtain ultrafine grains with an average grain size of 0.7μm. Microstructural evolution of the C-ARB processed aluminum alloy was examined by a transmission electron microscopy as a function of process cycle number (accumulated plastic strain). Tensile property of the severely deformed Al alloy was also explored. Grain size of grains of the C-ARB processed alloy varied across thickness of the rolled plate. The size of grains at the top and bottom of the rolled plate converged to 0.65μm, while that of grains at the center of the plate increased with the number of ARB cycles. Tensile strength of the CARB processed 1050 Al alloy increased from 100MPa (as-received) to 160MPa. Tensile elongation varied with the number of cycles, but 15% of failure strain was measured from the 6-cycle C-ARB processed specimen. The variation of the elongation with the cycle number coincided exactly with the variation of grain size at the center of the processed plate.

Evaluation on fracture toughness of low activation ferritic steel (JLF-1)

Low activation ferritic steels have been developed for a candidate of structural materials in nuclear fusion reactor applications. This paper dealt with the effects of rolling direction and side groove on the fracture toughness of low activation ferritic steel, JLF-1 Steel (9Cr-2W-V-Ta). The fracture toughness of JLF-1 steel showed the anisotropy in the rolling direction. In the case of J-R curve, JQ and slope of the longitudinal JLF-1 steel (BML) for the rolling direction were a slight larger than those of transverse JLF-1 Steel (BMT) at room temperature. In order to obtain the valid fracture toughness of JLF-1 Steel through the UC method, the CT specimen with a side groove of 40% was recommended. As one of low activation ferritic steels for the IEA test program, the JLF-1 (9Cr-2W-V-Ta) steel has been developed and investigated by the active cooperation of Japanese Universities (1,3,4). The low activation ferritic steels mounted in a high magnetic field such as fusion reactor components may be affected by the operating cycle and the mechanical vibration that is associated with the magnetic damping. For the sound design of fusion reactor, it is necessary to investigate the effect of magnetic damping on the mechanical properties of JLF-1 steel. Prior to its widespread, practical use, however, several fracture properties of the JLF-1 steel including tensile property, fatigue property and fracture toughness must be evaluated, preferentially. Especially, the investigation of fracture toughness and J-R curve is essential for practical applications of the JLF-1 steel into fusion areas, since it suffered from the elastic-plastic fracture behavior caused by the history of operation temperature. When the JLF-1 steel is used as the blanket structural material of fusion reactors, the experimental data for tensile properties and fracture toughness are very important to estimate safety life span of the blanket by critical crack length with the irradiation. The tensile properties and fracture toughness characteristics of unirradiated materials are required before the estimation of irradiated materials (2,5). Finally, the correlativity between magnetic field and fracture properties of JLF-1 steel should be established for its active application. Due to the limited amount of materials, the unloading compliance method with single-specimen method (ASTM E813-89), which was the alternative of multi-specimen method, was recommended for the examination of fracture toughness (6,9).