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The physical, mechanical properties and formability of sheet metal depend on preferred crystallographic orientations (texture). In this research work, we investigated texture development and formability of AA 3003 aluminum alloy sheets after asymmetry rolling and subsequent heat treatment. After asymmetry rolling, the specimens showed fine grain size. We also investigated the change of the plastic strain ratios after asymmetry rolling and subsequent heat-treating condition. The plastic strain ratios of asymmetrically rolled and subsequent heat treated samples are 1.5 times higher than the initial AA 3003 Al alloy sheets. These could be attributed to the formation of ND//<111> texture component through asymmetry rolling in Al sheet.

In this study, strong {0002} textured (or strong ND//<0002> textured) AZ31 Mg alloy sheets were prepared. These AZ31 Mg alloy sheets were cut along the angles of 0, 12.5, 25, 30 and 37.5 degrees to the rolling direction or {0002} texture. Prepared samples with different angles to the rolling direction were rolled at room temperature and after subsequent heat treatment, the bendability, ultimate tensile stress, elongation and texture are investigated using the 3-points bending tester, tensile tester and x-ray diffractometer, respectively. The specimen having along the angles of 0 degree to the rolling direction shows the highest load and 45 degrees specimen shows the highest displacement among any other specimens in the bending test. The specimen having along the angles of 12.5 and 25 degrees to the rolling direction shows highest elongation and of 0 degree specimen shows the highest ultimate tensile stress among any other specimens after cold rolling and subsequent heat treatment at 150°C for 30 minutes in bending test.

Formability is very important parameter of magnesium alloy sheets and it would be related to the texture of sheet metals. In this study, magnesium alloy sheets with strong {0002} texture were cut along the angles of 0, 12.5, 25 and 37.5 degrees to rolling direction (RD). Prepared samples were rolled at room temperature condition. Cold rolled AZ31 magnesium alloy sheets along the angles of 0, 12.5, 25, 37.5 and 45 degrees to rolling direction were investigated microstructure and texture with optical microscopy and x-ray diffractometer, respectively.

The effects of underwater friction stir welding (UFSW) on mechanical properties, strain hardening behavior, and formability of dissimilar materials of AA5052-O and AA6061-T6 welded joints were investigated. The mechanical properties of the UFSW joints exhibited higher strength and higher joint efficiency than the conventional friction stir welded joints (CFSW). The maximum joint efficiency of 73% has been attained for UFSW joints, which is due to the effect of welding atmosphere. The hardness of the stir zone (SZ) and heat affected zone (HAZ) are also obtained higher for the UFSW joints. Moreover, the hardening capacity, strain hardening exponent and formability of the UFSW joints were greatly improved over the CFSW joints. The improvement in mechanical properties of the UFSW joints is mainly due to faster cooling rate during welding. The microstructural characteristics revealed the formation of fine grains in the UFSW joints compared to the CFSW joints.

Cupro–nickel alloy of 70/30 grade was experimented for its formability by SPIF tests, namely straight groove test and wall angle test using a ball attached tool, to emphasize the concern on formability and surface roughness. Two different types of ball were used, one ball was used in polished form and another one was surface-textured using Nd-Yag laser. The cupro–nickel alloy has excellent corrosion resistance and popularly used in marine environments. In this research, an attempt has been made to study the formability when using Chrome steel laser ablated ball. The results concluded that Chrome steel laser ablated ball with oil as lubrication has avoided the occurrence galling and at the same time improved the formability. When experimenting with chrome steel polished ball, the tool and sheet contact is high and the lubricating oil will be less and it is causing the sheet to get heated. The dimples on the ball’s surface made by the laser retain more lubricating oil and thereby decreasing the friction which eventually leads to the delayed fracture. It is found that the formability was increased by 16% in straight groove test, 4.8% for wall angle test and surface roughness values were decreased by 1.4%.

The automotive industries are trying to optimize the forming and process parameters to reduce the weight of vehicle. Also, these optimized results are helpful to the manufacturer during decision making, so that overall product development or manufacturing time is reduced. In this paper, comparison of the strain paths, necking and fracture behaviors among the steel materials is performed. In this paper, the formability parameters such as strain path, thinning and contact pressures between die sets are studied. The strain path points are predicted by using FEA simulation in Pamstamp software for AISI304 and AISI409L grade material. The major and minor points are predicted at necking points for various specimens and these points are represented on FLD curve for both the materials. It is observed that AISI304 grade material showed higher formability i.e. 17% higher formability than the AISI409L grade material. The simulated and experimental results showed a closed match with good correlations though the variation between them is nearly 7%. Also, the microstructures are investigated by following standard metallographic process and after investigation it is observed that as the microstructure changes the locations of the deformed sheet parts also get changed.

Tube hydroforming (THF) is an unconventional manufacturing technique that uses pressurized fluid in place of conventional punches to deform the tubular blank into the desired shape. In THF process tubular blank is deformed it into the final shape by applying fluid pressure mostly by water using water intensifier through axial punches. Tube hydroforming is mainly used to produce hollow components using tubular blank which find applications in automobile industry, particularly for exhaust systems. The formability of Austenitic stainless steel tubes as function of microstructure is not focused much in literature. Hence, in this study, formability of Austenitic stainless steel tubes is studied as a function of boundary conditions and bulge width (L/D ratio) and correlated with microstructure. Microstructure resulting in axial feed condition showed better formability than microstructure resulting in fixed feed condition. Similarly, formability and fracture behavior of tube predicted with finite element-based simulation using PAMPSTAMP 2G solver found results, particularly bulge height and fracture location are in good agreement with experimental values. The observed fracture mode noted was ductile both for axial feed condition and fixed feed condition as the fracture consists of voids and micro voids. Fracture location was in base metal just, besides, weld line for axial feed condition and fracture location was in base metal which is little away from weld line for fixed feed condition.

In this paper, we report a comprehensive and systematic study for predicting the formability of double halide perovskites. Besides the tolerance factor, several complementary criteria for the formation and lattice distortion have been developed and compared with a throughout multivariate technique based on the principal component analysis (PCA) and the partial least square (PLS) methods. Some empirical equations expressing the relationships between the different ionic radii and the electronegativities and the lattice constants of double halide perovskites have been found.

The present contribution deals with the prediction of diffuse necking in the context of forming and stretching of metal sheets. For this purpose, two approaches are investigated, namely bifurcation and the maximum force principle, with a systematic comparison of their respective ability to predict necking. While the bifurcation approach is of quite general applicability, some restrictions are shown for the application of maximum force conditions. Although the predictions of the two approaches are identical for particular loading paths and constitutive models, they are generally different, which is even the case for elasticity, confirming the distinct nature of the two concepts. Closed-form expressions of the critical stress and strain states are derived for both criteria in elasto-plasticity and rigid-plasticity for a variety of hardening models. The resulting useful formulas in rigid-plasticity are shown to also accurately represent the elasto-plastic critical states for small ratios of the hardening modulus with respect to Young's modulus. Finally, the well-known expression of Swift's diffuse necking criterion, whose foundations are attributed in the literature to the maximum force principle, is shown here to originate from the bifurcation approach instead, providing a sound justification for it.

AA7075-T6 alloy shows poor formability at room temperature. In this paper, thermal experiments were first conducted to investigate the effect of different heat treatment conditions with AA7075-T6 alloy. Then thermal-mechanical uniaxial tensile experiment of AA7075-T6 were first carried out under different temperatures (100-475°C) in order to find the optimum forming conditions of AA7075-T6. And then the specimens were artificially aged at 120°C for 24 hours to regain the T6-temper properties after stretching. Results showed that AA7075-T6 formed at 475°C, 0.1s-1 had a significant improvement in elongation. The following artificial aging treatment produced equivalent material properties to the as-received T6 sheet. A modified Fields-Backofen constitutive equation of AA7075-T6 was obtained to describe the thermo-mechanical flow behavior of AA7075-T6 and then applied in FEM simulation of deep drawing box. Taking displacement as the criteria, results of numerical simulation proved hot stamping technology with HFQ process can improve the formability of AA7075-T6 high strength aluminum alloy.

Lightweight is the most effective way of saving energy and reducing emission, which at the same time must guarantees safety. Hot forming is an advanced technology, satisfying the demands of the lightweight of the car body and pedestrian's safety. Meanwhile, it is also an efficient approach to improve the competition of the products for automotive manufacturers. In this paper, a set of experimental setup was developed in order to investigate the formability of 22MnB5 at elevated temperatures. Then the forming limit diagrams of 22MnB5 at different temperatures were drawn and the effect of temperature on the formability of 22MnB5 was discussed.

In this study, self-lubricated galvannealed (GA) steel sheet was successfully developed by one-step method. The production process was introduced. The lubricating property, formability, weldability and phosphating performance of the steel sheet were studied. The comparison of material properties between the self-lubricated GA steel sheet and the traditional GA steel sheet was evaluated and studied. The results showed that the friction coefficient of the self-lubricated GA steel sheet was much smaller than that of the traditional GA steel sheet. The processing scope of the self-lubricated GA steel sheet showed a significant improvement compared to the traditional GA steel sheet. The weldability of the self-lubricated GA steel sheet is at the same level as that of the traditional GA steel sheet. Self-lubricated coatings on GA steel sheets can be easily removed during comprehensive pretreatment, with no negative effect on the subsequent phosphating process. All the properties of the self-lubricated GA steel sheet meet the technical demand of automobile manufacturers.

The material most immediately available for further light weighting body and chassis structures of mass produced automobiles is aluminium alloy and currently this is being used in relatively small quantities, mainly for premium cars. The main barrier to its wider use is its lower room temperature formability compared with that of deep drawing steel and, if to alleviate this, hot/warm forming is attempted, the low resulting mechanical properties. To overcome these drawbacks, the ‘Hot Forming and cold die Quenching’, HFQ^® process was conceived and subsequent research and development has resulted in a technology that has been proven to enable considerable light weighting of chassis and body structures to be achieved, with productivity and cost acceptable for mass production. This paper is a description of the mechanics of the HFQ^® process which provides a means for manufacturing components from sheet aluminium alloy with equivalent shape complexity and significantly lighter weight than of those from steel. The use of a suitable temperature and forming speed to enhance formability and means for obtaining high mechanical properties from heat treatable alloys are described. A number of components designed for both road and air production vehicles have been made using HFQ^® and some of these are presented together with estimates of production costs.

The elongation of aluminum alloy 7075 at room temperature is extremely low. To overcome the defects in cold forming methods, aluminum hot stamping process was proposed. This process can effectively improve the stamping formability of aluminum. In this paper, heat treatment experiments and deep drawing tests were used to study the formability of aluminum alloy 7075 in hot stamping process. In the deep drawing tests, the effect of hot stamping process parameters on formability were also studied, which can be used to improve hot stamping formability and reduce forming defects.

Based on the process of solution heat treatment(SHT)–forming–quenching–aging treatment, some tests of 6061 aluminum alloy were carried out in this paper, in order to guide the hot stamping of 6061 aluminum alloy. To investigate the influence of different temperature and time of SHT on the LDR value of 6061 aluminum alloy, this paper employed the method of SHT-hot drawing and then compared the formability in different conditions. This paper also investigated the effect of different aging time and temperature in mechanical properties, including tensile strength and hardness, by using the uniaxial tensile test and Vickers hardness test after SHT-quenching-artificial aging treatment at certain SHT temperature and time.

In response to the increasingly strict automobile exhaust emission standards, automakers have been increasingly adopting hot-stamped components to improve fuel efficiency and crash behavior. In this paper, the hot stamping for a B-pillar reinforcement of a SUV in B1500HS steel was studied by numerical simulation and experiment. The formability analysis for the B-pillar is emphasized firstly to determine the appropriate hot stamping process. Then, a finite element model was established and simulated by Dynaform. According to numerical simulation analysis, a set of optimal parameters is determined. Additionally, stress-strain states of the deformation zone and FLD of hot stamping were studied. Finally, the accuracy of the results and validity of the simulation method were verified by experiment. The results of micro-structure observation show that the micro-structure of B-pillar after hot stamping is lath martensite, and the Vickers hardness of B-pillar is more than 466 HV. This study verifies the feasibility of hot stamping process based on numerical simulation by experiment and provides important guiding significance for hot stamping production.

To solve the poor ductility of AA7075 aluminium sheets and serious spring-back in cold stamping at room temperature, an advanced hot forming-quenching integrated process for aluminium alloys, i.e., solution heat treatment - cold die Forming-Quenching (HFQ) is proposed and applied to a B-pillar outer panel in the automotive industry. In this paper, the HFQ of AA7075 is investigated experimentally. Firstly, the chemical composition is optimized in order to reduce the quench sensitivity. Secondly, the low melting point eutectic phase can be effectively eliminated by graded-homogenization. Thirdly, tensile tests, metallographic analysis and DSC are performed to optimize the suitable solution temperature. Fourthly, a series of hot tensile tests are conducted to investigate deformation characteristics at elevated temperatures. Fifthly, the CCT curve is simulated by JMatPro to determine the quenching cooling rate of the AA7075. Finally, the forming process of the AA7075 aluminium sheets is simulated by CAE software. The results show that the B-pillar component demonstrated limited spring-back with a high level of dimensional accuracy after the forming/quenching operation at appropriate solution temperature and an artificial aging process.

The physical, mechanical properties and formability of sheet metal depend on preferred crystallographic orientations (texture). In this research work, we investigated texture development and formability of AA 3003 aluminum alloy sheets after asymmetry rolling and subsequent heat treatment. After asymmetry rolling, the specimens showed fine grain size. We also investigated the change of the plastic strain ratios after asymmetry rolling and subsequent heat-treating condition. The plastic strain ratios of asymmetrically rolled and subsequent heat treated samples are 1.5 times higher than the initial AA 3003 Al alloy sheets. These could be attributed to the formation of ND//<111> texture component through asymmetry rolling in Al sheet.

In this study, strong {0002} textured (or strong ND//<0002> textured) AZ31 Mg alloy sheets were prepared. These AZ31 Mg alloy sheets were cut along the angles of 0, 12.5, 25, 30 and 37.5 degrees to the rolling direction or {0002} texture. Prepared samples with different angles to the rolling direction were rolled at room temperature and after subsequent heat treatment, the bendability, ultimate tensile stress, elongation and texture are investigated using the 3-points bending tester, tensile tester and x-ray diffractometer, respectively. The specimen having along the angles of 0 degree to the rolling direction shows the highest load and 45 degrees specimen shows the highest displacement among any other specimens in the bending test. The specimen having along the angles of 12.5 and 25 degrees to the rolling direction shows highest elongation and of 0 degree specimen shows the highest ultimate tensile stress among any other specimens after cold rolling and subsequent heat treatment at 150°C for 30 minutes in bending test.

Formability is very important parameter of magnesium alloy sheets and it would be related to the texture of sheet metals. In this study, magnesium alloy sheets with strong {0002} texture were cut along the angles of 0, 12.5, 25 and 37.5 degrees to rolling direction (RD). Prepared samples were rolled at room temperature condition. Cold rolled AZ31 magnesium alloy sheets along the angles of 0, 12.5, 25, 37.5 and 45 degrees to rolling direction were investigated microstructure and texture with optical microscopy and x-ray diffractometer, respectively.