GLARE Hydro-Mechanical Deep Drawing Analysis Based on the Forming Depth

The Fiber metal laminates (FMLs) combine the advantages of fiber-reinforced polymer properties, like stiffness and strength, with metallic alloys, like toughness and durability. These hybrid materials can unravel some problems in the industrial sector, particularly in aerospace, and advanced automotive industry. Still, there are significant challenges in the GLARE sheets forming process even for small drawing ratios, notably smaller and complex-shaped fiber metal laminate with low thickness. As a case study, a cylindrical GLARE cup was chosen. This shape with sharp bends and vertical geometrical features, still face many challenges and difficulties in the forming process. Numerical simulations have been used utilizing ABAQUS and compared with the experimental results in the Hydro-mechanical deep drawing to achieve good forming quality with higher depth. An extensive investigation of the effect of process variables has been done such as cavity pressure, blank holding force, and blank diameter. Also, their roles in wrinkles formation, tearing and thinning, and formability has been performed. Furthermore, the friction in two cases; cured, and semi-cured condition, has been considered. The results show that the application of cavity pressure within specified limits has a positive effect on the quality of the formed cup and leads to higher depths. The same conclusion for the blank holder, which has a positive impact on wrinkling elimination and friction reducing between the aluminum layers and the fiberglass. The result shows that the semi-cured condition of the GLARE has a good effect on wrinkling reduction, due to the uniform movement of the fiberglass inside the aluminum layers. Understanding these parameters and the GLARE forming behavior and have a good selection of these parameters can give the advantage to achieve smaller and more complex shapes with higher depth, particularly for mass production. Finally, this study can extend the industrial application areas of FMLs and GLARE parts.

The Effect of Elevated Temperature on the Drawability of a Circular Deep Drawn Metal Cup

Product quality is one of the important aspects in deep drawing practice and the variation in process temperature was claimed to improve the quality. Therefore, in this research, the effect of the heating temperature on the drawability of a circular metal cup has been investigated. Firstly, circular metal cups of aluminium, mild steel and stainless steel were drawn from the blank diameters of 60 mm, 65 mm, and 70 mm. The experiment was conducted at room temperature followed by at 100 °C, 150 °C and 200 °C. The Taguchi method was selected as the design of experiment approach, and L9 (34) array design methodology was adopted in this experimental research. The drawability was measured based on the punching force needed to deform the sheet metal blanks. The deep drawing process was conducted at room, and elevated temperature conditions and the response factor was analysed and compared through the analysis of variance (ANOVA) statistical approach. The results obtained from ANOVA indicate that the blank material has a significant influence on the deep drawing process followed by the blank size, heating temperature and heating technique. The optimal parameter combinations are blank diameter of 60 mm, heating temperature of 200 °C and the die and punch heating technique. Out of the three materials investigated, aluminium has a better drawability compared to mild steel and stainless steel.

The importance of forming parameters on rolling process and the performances of component in forming long threads

The axial self-infeed rolling process is an advanced and efficient process to form long threads such as lead screw and thread shaft. The experiments of axial self-infeed rolling process for the stainless steel were conducted with three blank diameters, forming speeds and two lubrication conditions. The effects of forming speed, blank diameter and lubrication condition on forming torque, microhardness and tooth height of forming threads were analyzed by the design of experiment and analysis of variance. And the characteristics of forming torque, microhardness distribution and tooth height were investigated. The results revealed the forming torque was more influenced by the blank diameter and the forming speed than the lubrication condition. The tooth height was sensitive to all these factors and the microhardness only was affected by the blank diameter.

Experimental Evaluation and Finite Element Simulation to Produce Square Cup by Deep Drawing Process

Deep drawing process to produce square cup is very complex process due to a lot of process parameters which control on this process, therefore associated with it many of defects such as earing, wrinkling and fracture. Study of the effect of some process parameters to determine the values of these parameters which give the best result, the distributions for the thickness and depths of the cup were used to estimate the effect of the parameters on the cup numerically, in addition to experimental verification just to the conditions which give the best numerical predictions in order to reduce the time, efforts and costs for producing square cup with less defects experimentally is the aim of this study. The numerical analysis is used to study the effect of some parameters such as die profile radius, radial clearance between die and punch, blank diameter on the length and thickness distributions on the cup, dynamic-explicit (ANSYS11) code based on finite element method is utilized to simulate the square deep drawing operation. Experiments were done for comparison and verification the numerical predictions. effective square cup with less defects and acceptable thickness distributions were produced in this study. It is concluded the most thinning appear in the corner cup due to excessive stretching occur in this region and also it is found the cup thickness and height prediction by numerical analysis and in general in harmony with experimental analysis.

Evaluation of Limiting Drawing Ratio (LDR) in deep drawing process

Part production by deep drawing technology brings important economic advantages. Cupping test is used to determine material suitability for deep drawing. The main principle of the test is redrawing of cylinder metal test piece to the cup. The result of the test is calculation of limiting drawing ratio (LDR) whichstates the ratio betweenthe largest blank diameter and final cup diameter. Many cupping tests for various materials were performedin order to determine maximal value of LDRthatwould still allow deep drawing without failure of material integrity. Limiting drawing ratio (LDR)converges to Euler’s number (e) for high test piece depth and final cup diameter ratio values. Theoretical analysis of the cupping on drawing die with tractrix curve shows that maximal value of LDR may achieve value LDR>e. This is possible at lower values of test piece depth to final cup diameter ratio.Evaluated values of LDR published in reference literature do not include description ofstrict test conditions. Coefficient of friction has determining influence on LDR value. The theory of limiting drawing ratio(LDR)evaluation described in this paper regards the influence of coefficient of friction between drawing die and drawing cup.

Determination of the Optimal Blank Diameter in the Case of Mini Deep Drawing by Applying the Fuzzy Logic and Taguchi Methods

An important problem in obtaining mini drawn parts with high precision is represented by the blank geometry. Utilization of a blank with optimal shape and dimensions leads to the following benefits: improves the accuracy of the drawn parts and determine the costs reduction due to reduced material consumption and cost, lower number of technologic operations, shorter manufacturing times etc. An adequate blank prevents the following effects on drawn part: avoids the part fracture, conducts to a uniform distribution of the material thickness in drawn part and reduces the blank holder force required by the drawing process. The present paper analyses the results of investigations made by simulation and experiment concerning the establishment of the optimal blank diameter in the case of mini cylindrical drawn parts made from aluminium sheets. The optimal blank diameter was determined by applying the Fuzzy Logic and Taguchi methods.

Research on Flange State during Spinning of AZ31 Magnesium Alloy Rotators

The stress-strain condition and flange state during spinning of magnesium alloy rotators was researched. The preliminary conclusion is obtained: There are three states during spinning of rotators, which appropriate "forward" and "straight" is conducive to forming, but the "backward" should be avoided. Based on ABAQUS/Explicit platform to analyze flange state and forming quality of these rotators under various load conditions. FE analysis shows: blank diameter, roller structure and feed ratio are key factors of formability. Most favorable process parameters are blank diameter 160mm, feed ratio 0.8r/mm, while using combination roller. Finally, the role of the main process parameters on flange state was verified by experiment method.

A Study on DOE Methods for Hydromechanical Deep Drawing Process Parameters

Formability of sheet metals can be increased by Hydromechanical Deep Drawing (HDD) process. Formability of the deep drawn cups is generally assessed by Limiting Drawing Ratio (LDR) which is the ratio of the blank diameter to punch diameter. In order to increase LDR by HDD, process parameters of the HDD should be arranged properly. Arranging of the process parameters requires a great knowledge about the effects of the process parameters to certain performance criteria of the process. Determining of the effects of the process parameters by full factorial experiments is a hard duty. Hence certain statistical methods that decrease the number and the cost of the experiments and reduce the time should be used to find effective parameters and their appropriate levels. In this study orthogonal experimental array was applied and effective process parameters were determined by analyzing predicted data with Taguchi's robust parameter design method and ANOVA method. Then the results were compared with each other to evaluate differences between the methods. By using the appropriate levels of the parameters the LDR of AA 5754 aluminum alloy which uses in automotive industry intensely was determined.

Formability of Magnesium-Lithium Alloy Sheet by Multi-Stage Deep Drawing

The formability of the magnesium-lithium alloy was examined by multi-stage deep drawing. Long cups of magnesium alloy were formed at ambient temperatures by multi-stage deep drawing processes. In multi-stage deep drawing, the magnesium-lithium alloy sheets were employed and a flat sheet blank is formed into a cylindrical by a punch. Various cups were drawn by exchanging the punch and ringed die. The die was flat in the first stage, and was taper without a blankholder in the subsequent stages. The effects of the ratio of blank diameter to punch diameter and blank thickness on the deep drawability were examined. It was confirmed that the Mg-Li alloy long-cups were successfully formed by a multi-stage deep drawing operation in cold.