Formability Of Aluminum Research Articles

Investigation and optimization on the formability of aluminum 1050/stainless steel 304L bilayer sheets fabricated by cold roll bonding considering the Box-Behnken method

Composite metal sheets have found extensive applications thanks to their high corrosion and wear resistance, as well as greater strength, stiffness, and formability relative to the base sheets. Stainless steel composite sheets account for over 80% of the metallic composite sheets. Their higher performance and lower costs have increased their applications in the food and automotive industries. This study experimentally addressed the formability of the Al 1050/Stainless Steel 304 L bilayer sheets prepared through the cold rolling process. After designing the experiment using the response surface method, considering the layer thickness and reduction ratio of the rolling process, the bilayer sheets were prepared using the cold roll bonding process. Formability included the forming limit diagram, the magnitude of FLD0, and elongation, which were derived by Nakazima and tensile tests. Then, the formability was optimized as a function of input parameters considering the Box-Behnken method. To this end, a new criterion was presented to compare the formability of the sheets. This criterion can be used to assess the formability of a sheet considering various loading modes. Microstructural observations justified the variations in the formability of the bilayer sheets against the input parameters, i.e., thickness ratio and reduction ratio. The results indicated that the formability of the Al 1050/Stainless Steel 304 L bilayer sheet (i.e., safe forming region) reached its maximum value at tAl=4mm;tSS=0.8mm;andr=45%.

Experimental study on drawability of aluminium-copper composite in micro deep drawing

To meet the increasing demand of multifunctional applications of microcomponents, metal composites have been gradually noted in micromanufacturing. In this paper, the formability of aluminium (Al)-copper (Cu) composite foils in micro deep drawing (MDD) was studied, and the mechanism involved was discussed. A two-layered Al-Cu composite with the thickness of 235 µm was selected and first rolled to 50 µm, and then annealed at 200, 300, 400 and 500 °C for 5 min prior to the MDD experiments. The results show that Al-Cu composite foil possesses the best combination of strength and ductility after annealing at 400 °C. With the increase in annealing temperature, the grains of both Al and Cu layers are refined, and in the meantime, the thickness of intermetallic layer also increases. The results from MDD tests indicate that the existence of intermetallic layer has a greater influence on the formability of the composite foil compared to the finer distribution of grains. On the basis of the obtained results, the optimised heat treatment method with the annealing temperature of 300 °C for 1 h was proposed, which was then proved to significantly improve the performance of the Al-Cu composite foil in MDD.

Formability of Aluminum in Incremental Sheet Forming

Single point incremental forming (SPIF) process is used to deform complex shapes. Through SPIF process metallic sheet is formed. The formability of a AA5052 is evaluated using SPIF method for industry level product. The utility of SPIF is broad in industries because of the simple operating system of manufacturing and designing metal substances throughout computer design combined with the CNC machine. While forming Mantellic sheet there are many benefits. This process is extensively adopted in automobile, aeronautical, and medical industries for engineering complex parts. In this paper, the main objective is to examine the formability of AA5052 aluminum alloy raw material with various wall angles and operating boundaries using the modified computer numerical control (CNC) milling machine. Here, the shape correctness and the surface roughness are focused for computing the forming depth, wall angle, and spring-back for obtaining improved parts with a proper material with finish surface. For verifying the real-time experiments and evaluating the existence of stress, strain, and thickness variations.

A Measure of Optimization of Technological Parameters to Improve the Formability of Aluminum Sheet a 1050 H14 by SPIF Technology

The objective of this paper is to select a set of technological forming parameters including vertical feed Δz, feeding rate of Vxy of the tool (a kind of pestle but no-cutting edges), the diameter of tool D and the revolutions per minute of tool n to achieve the highest forming ability of aluminum sheet A1050 H14 (according to JIS G3101Japanese standard) when forming metal sheet by Single Point Incremental Forming Technology-SPIF. The content of the article consists of 3 processes: Pre-design of experiment (Pre-DOE) to select of a set of reasonable limited parameters when forming aluminum sheet A1050 H14 models when forming on the existent specialized SPIF machine in the National Key Laboratory of Digital Control and System Engineering laboratory (DCSELAB); Performing aluminum sheet A1050 H14 models on the Pre-DOE to obtain the forming angle values; Evaluating the experimental results by analysis of variance; Setting up the regression equation of the angle of deformability with influence parameters; Optimization the regression equation to select an optimal set of forming parameters to gain the highest deformability of aluminum sheet A1050 H14.

Improvement in forming process using Magnetorheological Fluid Assisted Cushion in Hydraulic Press

The role of cushion pressure in hydraulic press plays a vital role in forming the component. In the present work, an attempt was made to analyse the influence of Magnetorheological cushion in addition to the existing cushion system, in forming small cup shaped component. The innovative Magnetorheological assisted hydraulic press of 1 ton capacity is designed and fabricated. The formability of Aluminium and Galvanised Iron sheet of different thickness was analyzed. The Magnetorheological cushion improves the formability of components with the reduced number of wrinkles in it. The forming process with the Magnetorheological fluid assisted cushion hydraulic press was more efficient than ordinary hydraulic presses.

Accounting for the effect of heterogeneous plastic deformation on the formability of aluminium and steel sheets

Forming limit curves characterise “mean” failure strains of sheet metals. Safety levels from the curves define the deterministic upper limit of the processing and part design window, which can be small for high strength, low formability materials. Effects of heterogeneity of plastic deformation, widely accepted to occur on the microscale, are neglected. Marciniak tests were carried out on aluminium alloys (AA6111-T4, NG5754-O), dual-phase steel (DP600) and mild steel (MS3). Digital image correlation was used to measure the effect of heterogeneity on failure. Heterogeneity, based on strain variance, was modelled with the 2-component Gaussian mixture model, and a framework was proposed to (1) identify the onset of necking and to (2) re-define formability as a probability to failure. The results were “forming maps” in major-minor strain space of contours of constant probability (from probability, P = 0 to P = 1), which showed how failure risk increased with major strain. The contour bands indicated the unique degree of heterogeneity in each material. NG5754-O had the greatest width (0.07 strain) in plane strain and MS3 the lowest (0.03 strain). This novel characterisation will allow engineers to balance a desired forming window for a component design with the risk to failure of the material.

Enhancement of the Forming Limits for Orbital Formed Tailored Blanks by Local Short-term Heat Treatment

Nowadays, the manufacturing industry faces opposing challenges like a reduction of carbon dioxide on the one hand and on the other hand an increasing weight due to higher safety standards and additional functions. Concepts like lightweight design and functional integration are essential to ensure a sustainable and individual mobility. Gear systems consist of multi-functional parts with a varying sheet thickness and different geometric elements. Since conventional manufacturing processes like shearing are reaching their limits due to complexity and a lack in efficiency, the application of Tailored Blanks is a promising approach to meet these requirements. Manufactured by orbital forming, these process-adapted blanks dispose a high material efficiency. A tumbling motion of the upper punch enables the material distribution, realizing functional components with different material thickenings. The substitution of steel by aluminum is a common approach to meet the demands of lightweight construction. However, the use of aluminum results in a decreased formability at a constant level of strength. In order to enhance the local forming limits, a short-term heat treatment can be applied, reducing the materials’ strength, whereas the untreated areas still offer the initial properties. To transfer the results of fundamental research in Sheet-Bulk Metal Forming with conventional steel to the use of lightweight material, the precipitation hardenable aluminum alloy EN AW 6016 is investigated in an orbital forming process. Since the formability of aluminum is limited and the material flow during the process is three-dimensional, different heat treatment strategies are applied to a rotational-symmetric Tailored Blank and the resulting components are investigated regarding their geometry and mechanical properties. To increase the geometric complexity with regard to an industrial application, the transferability to a cyclic-symmetric layout is analyzed. To evaluate the potential of the heat treatment, the treated components are compared to Tailored Blanks manufactured without heat treatment.

Investigation of EN AW 5754 Aluminum Alloy’s Formability at Elevated Temperatures

Nowadays, mass reduction is the most often used term in the automotive industry. Car manufacturers are continuously working on getting ever lighter models than the previous ones, because of the global competition and the rigorous emission rules. A light car has many advantages: lower consumption, better handling, longer operating distance, etc. The emission rules forced the car brands to start new researches to find new solutions for mass reduction. The formula is relatively simple, using lighter or less materials or both and the car will be lighter. In the recent solutions there are three different ways: application of high strength steels, aluminum alloys, and carbon-composite elements. Our investigations are focusing mainly on aluminum, because of its high mass reduction potential. The biggest problem with the aluminum is its low formability. The formability of aluminum is lower than the steel, and it causes problems for the manufacturers. To increase the formability of the aluminum is a hot topic in the research and development area. Forming at elevated temperatures is one of the best solutions to increase the formability of aluminum. The relation between the formability and the forming temperature is not linear, furthermore beyond the optimum forming temperature the formability decreases. We need dozens of investigations to describe the perfect relation, but sometimes a good approximation is enough to form sheet products safely. In our work we investigated the EN AW 5754 aluminum alloy sheet at room temperature, 130°C, 200°C and 260°C. From these tests we could obtain FLC curves of the alloy at different temperatures. Using these curves, the process engineers could find the optimum parameters of their forming process.

Formability Analysis of Aluminium Alloy by Erichsen Cupping Test Method

The forming behavior of aluminum sheet in selected samples with proper annealing and chemical composition for better formability was investigated by Erichsen Cupping test method. In this paper, the formability characteristics of aluminum alloys AA1200 sheet metals are studied. The results showed that the formability of aluminum having better forming property and ductility.

Parametric Study on the Electromagnetic Force-Fit Joining of Carbon Fiber Reinforced Plastic and Aluminum Tubes

Abstract An electromagnetic force-fit joining of carbon fiber reinforced plastic (CFRP) and aluminum tubular parts is studied. In this process, by discharging the energy stored in the pulse power into a coil, the aluminum tube is compressed to the CFRP tube and a force-fit joint is created. CFRP as a high strength material is used as inner part and an aluminum tube is assembled to it as the outer part. The assembled tubes are placed in an EMF compression coil and the joint is created. Due to the high elastic recovery of CFRP as well as a high formability of aluminum, force-fit mechanism results in a proper joint of the CFRP and aluminum tubes. Influence of different process parameters including the discharge energy, gap between inner and outer parts, workpiece thickness and usage of a supportive mandrel is investigated by the tensile test of the joint samples. The Taguchi’s design of experiments is used in order to decrease the number of experimental tests and optimum process conditions are obtained. The results indicated that the force-fit joining method can be successfully used for joining the aluminum and CFRP frames.

Numerical and experimental investigation of pulsating blankholder effect on drawing of cylindrical part of aluminum alloy in deep drawing process

In this study, the effect of a new pulsating blankholder system has been investigated on improving the formability of aluminum 1050 alloy. By using this system, during each pulsating cycle, first, the metal was easily flowed into the die through removing the blankholder force, and then the blankholder force applied by springs was employed to prevent excessive metal flow and wrinkling. Deep drawing of cylindrical cup was simulated by ABAQUS6.7 software. Cup depth, tearing, and thickness distribution of the experimental and numerical analyses were then compared. The results indicated that by using the pulsating blankholder system coupled with proper frequency and gap, the cup depth can be increased and thickness distribution can be improved. Further, good agreement was observed between simulation and experimental results.

Formability of aluminium embossing sheets with controlled stamping machine for PEM fuel cell

The weight of bipolar plates is one of the important considerations in the process of improving the power density in proton exchange membrane fuel cell stacks. An aluminium alloy not only has good mechanical properties such as low density, low electrical resistivity and high thermal conductivity, but also has high corrosion resistance. Furthermore, when aluminium is used as a material for bipolar plates, the cost and weight of the bipolar plate can be reduced, and machining becomes easier. Therefore, in this study, an aluminium alloy is selected as the ideal material for a bipolar plate. In this paper, the results of feasibility experiments conducted with the aim of developing fuel cells in which Al bipolar plates with multiple channels are presented. This investigation involves determination of the effect of machine velocity and die temperatures on the formation of microchannels using thin metal sheets of Al5052. The experimental results demonstrate the feasibility of the proposed manufacturing technique for producing bipolar plates.

Effect of annealing on formability and crystallographic textures of aluminium 5052 alloy sheets

Abstract In this work, forming and fracture limit diagrams have been experimentally evaluated for aluminium 5052 alloy sheet annealed at four different temperatures namely 200°C, 250°C, 300°C and 350°C. With the help of these diagrams, the safe range which avoids necking and fracture during forming of aluminium 5052 alloy sheets was examined and the effect of annealing temperature on this range and other parameters namely microstructure, tensile properties and formability parameters were studied. The forming limit diagrams of aluminium 5052 alloy sheets annealed under different temperatures were also examined with respect to the crystallographic texture point of view. The crystallographic textures were then correlated with normal anisotropy of the sheet metal. It was found that the formability of aluminium 5052 alloy annealed at 350°C possessed good formability, optimal texture and high normal anisotropy value.

アルミニウムおよびマグネシウム合金板の温間成形性(機械材料・材料加工II)

アルミニウムおよびマグネシウム合金板の温間成形性(機械材料・材料加工II)

419 インクリメンタルフォーミングによる微小シェルパーツの成形(O.S.8. 微細精密加工と材料)

The forming process of millimeter or submillimeter shell parts using incremental sheet metal forming technique was tested. The formability of aluminium, copper and stainless steel foils into quadrangular pyramid-shaped shell parts were examined. In this process the pinhole defects were formed in the steeper wall and thin workpiece. In order to prevent the defect, new tool path in which the local strain concentration is controlled was proposed. By this tool path the steeper wall was formed successfully.

Formability of aluminium and steel sheets

The formability of soft aluminium, half-hard aluminium, and deep-drawing quality steel sheets was compared using the material parameters r, n, and m, and the forming-limit diagrams. Strain hardening in uniaxial and biaxial tension was found to be the the same, justifying the use of the uniaxial n valuefor the assessment of formability. The necking-limit strains of the soft aluminium and steel were quite similar, the inferior press behaviour of aluminium being a result of smaller r and m values

アルミニウム被覆鋼に関する研究（第2報）薄鋼板の成形性について

アルミニウム被覆鋼に関する研究（第2報）薄鋼板の成形性について