The importance of manufacturing of hydrogen fuel tanks due to the application of hydrogen fuels in clean and recyclable energy is one of the most important issues of substituting the petroleum fuels. They consist of two main parts: Plastic liner, as a barrier escape of hydrogen and Carbon Fiber Reinforced Polymer (CFRP) layer to strengthen tanks. The liner plastic could be manufactured by rotational

Friction Stir Welding (FSW) is one of the most used solid-state welding processes in the aeronautical, aerospace, ground transportation and naval fields. Stationary Shoulder Friction Stir Welding (SSFSW) is a recently introduced variant of the process allowing lower heat input into the joints, with beneficial effects in terms of joint mechanical properties, microstructure and top surface finish. In

The present paper deals with preform deformation and resin flow coupled to cure kinetics and chemo-rheology for the VARTM process. By monitoring the coupled resin infusion and curing steps through temperature control, our primary aim is to reduce the cycle time of the process. The analysis is based on the two-phase porous media flow and the preform deformation extended with cure kinetics and heat transfer

Laser-assisted tape winding (LATW) is a highly automated process for manufacturing tubular-like fiber-reinforced thermoplastic composites such as flywheels and pipes. One of the crucial parameters in the LATW process is the temperature of the nip point at which the incoming prepreg tape is bonded with the substrate by a compaction roller. Therefore, the temperature evolution of the nip point plays

A tailored tempering process, whereby the cooling rate for the sheet is controlled to form regions with very high strength and regions of reduced strength but increased ductility. In order to obtain the optimal mechanical properties for CSC-15B22 steel sheets that undergo tailored tempering, experimental and simulation method are used to examine the tempering process. The heated die section is heated

The original publication of this article unfortunately contains error. The word “extrusion” was spelled incorrectly as “extrussion” in the article title.

The predictability of strain distributions and the related prediction of hardening and failure plays a central role in tool and process design for any metal forming process. Studying yielding behaviour, it was discovered that for various well established yield loci no satisfying agreement between DIC (digital image correlation) measurement of strain distribution and simulation result could be obtained

Microwave (MW) technology relies on volumetric heating, where thermal energy is induced from an electromagnetic field. Nowadays, the main drawback of this technology is that the complex physics involved in the conversion of electromagnetic energy into thermal energy is not entirely understood and controlled. The main objective of this work is to model, simulate and validate the interactions of microwaves

Non-intrusive approaches for the construction of computational vademecums face different challenges, especially when a parameter variation affects the physics of the problem considerably. In these situations, classical interpolation becomes inaccurate. Therefore, classical approaches for the construction of an offline computational vademecum, typically by using model reduction techniques, are no longer

During the stretch blow moulding (SBM) process of polyethylene terephthalate (PET) bottle, high viscous dissipation generates self heating phenomena. Since the influence of temperature on polymer’s behavior is important, it is necessary to evaluate the self heating values in order to manage accurately the simulation of the process. An anisotropic visco-hyperelastic model has been developed to manage

The simultaneous hot/cold forging is an innovative production process, taking advantage of the high accuracy for cold forming and low forces for hot forming. However, the choice of a suitable material model for such a large temperature range is a difficult issue and insufficiently regarded. Hence, the aim of this contribution is a critical review and assessment of the prediction capability and accuracy

During the extrusion of thermoplastic particulates, the major problem is to adjust and optimize the experimental conditions of temperature and rotational speed of the screw, to decrease porosity defects, resulting from the coalescence of the polymer grains. In this work, a study of high-density polyethylene (HDPE) coalescence as a function of temperature and shear rate is conducted, with modeling of

Continuous Glass Fiber-Reinforced Thermoplastic Composites (GFRTC) were successfully prepared using two different routes: a reactive laboratory-created approach as well as a compression molding method. Two kinds of high-performance polyphtalamides (PPA) were studied: PPA from a chain extension reaction of its parent prepolymer (named R-PPA) in comparison with a virgin non-reactive PPA (NR-PPA). For

Unsaturated-polyester/glass-fiber composites are worldwide more and more used. Actually, their thermochemical and mechanical recycling paths are quite well-known. But, due to the relatively low value of the end products, these two paths are hardly economically viable. Thus, a third way will be proposed as a thermomechanical path. In order to recycle these composites, a study of their thermo-mechanical

A novel differential lubrication method is proposed to improve the deformation behavior of L-shaped thin-walled with relative bending radius of 1 in push-bending process. The optimized tube blank is divided into four zones: inner deformation zone, inner guide zone, outer deformation zone and outer guide zone, which are lubricated with different lubricants. The differential lubrication and uniform lubrication

The hot deformation behavior of a multi-direction forged (MDFed) T2 copper was investigated by the isothermal compression test at deformation temperatures between 673 and 1173 K and strain rates between 0.001 and 10 s− 1. The results reveal that the deformation characteristics of the flow stress are sensitive to the hot deformation parameters. The deformation activation energy of the MDFed copper under

In this study, the effects of the single and multiple productions of samples by additive manufacturing on residual stress and displacement (distortions) were investigated. The samples were manufactured by Selective Laser Melting (SLM) machine using Ti6Al4V powders. Each time a different number (1, 5 and 13 samples) of cubic shaped samples were produced on the building platform. During the process,

This paper presents an experimental and numerical investigation into the effect of pre-heat temperature on stretch forming of a fibre metal laminate (FML) comprised of alternating layers of steel and woven (0/90) glass-fibre polypropylene in a 2:1 configuration. Hourglass sample geometries were formed in an open die and real-time photogrammetry was used to measure the evolution of strain fields over

The Forming Limit Diagram (FLD) is an essential tool to assess sheet metal formability in sheet metal deep drawing. In FLDs/FLC (Forming Limit Curve) is representation of material formability limits at which material is not able to withstand higher deformation. In this work, different methodologies for FLC determination of mild steel DC01 are investigated. The Nakajima test is a well-known experiment

Nowadays, polyamide 12 (PA-12) is considered as an interesting polymer in the rotomolding process to manufacture different pieces like the liner part in the storage hydrogen tank (type IV). In this study, the pure polyamide-12 and PA12 pieces, incorporated with 0.5%, 1% and 3% wt Nano Carbon Black (NCB), were manufactured by the rotomolding process. Different rotomolding parameters such as heating

Production efficiency in metal forming processes can be improved by implementing robust optimization. In a robust optimization method, the material and process scatter are taken into account to predict and to minimize the product variability around the target mean. For this purpose, the scatter of input parameters are propagated to predict the product variability. Consequently, a design setting is

For conventional material models like Yld2000-2d or BBC05 the equi-biaxial yield strength is required for the parameter identification. In this context, a commonly used test setup is the hydraulic bulge test. However, an inaccuracy in the characterization of the initial yield strength is present in the hydraulic bulge test. Due to the evaluation of the resulting curvature of the specimen, that is nearly

The objective of the research is to determine the effect of friction stir processing (FSP) parameters and vibration on the machining behavior of AZ91 alloy. The article displays the state of the art of AZ91 alloy machinability including chip formation, chip morphology, and cutting forces. In this method, the vibration was applied to the process line through the fixture under the workpiece during the

In this paper, specimens were first pre-stretched to different pre-strain coefficients (0, 0.4 and 0.8) under quasi-static tensile for AA6061-O aluminum alloy. Then, the specimens with different pre-strain coefficients were stretched by a high-speed tensile machine (HTM) at different strain rates (200 s− 1, 400 s− 1 and 600 s− 1). Digital image correlation (DIC) technique was employed to measure the

Aeronautical companies are manufacturing many components of small (less than 200 mm) and medium (between 200 mm and 1000 mm) sizes by flexforming. In order to diversify the production facilities of these components, these companies are interested in evaluating the ability of electromagnetic forming processes to produce small parts. This paper describes the design of a set of experiments of electromagnetic

This paper proposes an innovative electromagnetic forming process for the manufacturing of aluminum alloy tubes, namely electromagnetic impacting medium forming (EIMF) process using flat spiral coil. The proposed EIMF process was implemented and characterized by numerical and experimental methods. Based on medium height and discharge energy, deformation region of tube was analytically determined and

Recent advances in mechanical and civil engineering are noticed in many innovative designs that frequently employ cold-formed High Strength Steels (HSS). Typical mobile cranes benefit from the advanced properties of these steel grades in a bent configuration. Here, the majority of load-carrying members are produced through cold-bending and subsequent welding procedures. These cold-foring processes

The quality of thin strip products is determined by the flow and heat transfer in a molten pool of twin-roll casting, thus it is of great significance to study the structure parameters of the delivery system, including the angle and height of end face nozzle, the angle and height of side nozzle as well as the taper angle of side nozzle. A methodology for simulation of twin-roll thin strips continuous

Reliable sheet metal forming simulations depend on accurate descriptions of real process conditions. These conditions include material behavior, lubrication systems, tool deformations, press dynamics, and more. Research on material models is the most mature area for describing these conditions in a reliable way. Several advanced and flexible models exists. This study focuses on two versions of yield

The hot deformation behaviour of one 7XXX series aluminium alloy, 7A04, has been studied by conducting isothermal hot compression tests with degree of compression up to 55% at the temperature ranging from 350 °C to 480 °C and strain rates ranging from 0.002 s−1 to 20s−1. Based on characteristic of the flow stress obtained from those tests, an extended Voce equation, which constant parameters were modified

Hole flanges are commonly manufactured in mass production by conventional press-working. In an industrial context, the process limits are usually evaluated by means of the Limiting Forming Ratio (LFR), which defines the maximum attainable diameter of the flange related to the initial pre-cut hole. Nevertheless, the LFR does not provide enough information about material deformation, thickness distribution

Radial-Axial Ring Rolling (RARR) is an industrial forging process for making strong, seamless metal rings. Conventionally, rings are made circular with constant cross-section. In this work we demonstrate a sensing and control strategy to create rings with variable radial wall thickness and variable curvature using standard RARR hardware. This has a number of potentially useful applications but also

In this study, to eliminate the extrudate swell, melt fracture and extrudate distortion problems of polypropylene (PP) micro-tube, the experiments of gas-assisted extrusion forming was firstly carried out. Meanwhile, a set of modified gas-assisted extrusion system was set-up, and a kind of novel gas-assisted die was also designed and manufactured. Under the role of gas-assisted extrusion system, PP

To accurately model warm and hot forming operations, correct values for heat transfer coefficient (HTC) are required, among other parameters. In this work, an experimental methodology is proposed to obtain HTC data for a high strength steel alloys (Usibor® 1500 A-S), seven aluminum alloys (AA5182-O, AA5754-O, AA6013-T6, AA6063-T6, AA6061-T6, AA7075-T6 and a developmental AA7xxx-T76) and two magnesium

A new analytical method to determine the effective tool width in contact with the sheet workpiece in the plane strain compression test, which changes during the test if a tool with a radius is used, is proposed. A detailed description of this method and the corresponding procedure of the flow curve determination for high-strength sheet steels are presented. The underpinning assumptions of the method

The optimization of extrusion of energetic materials is a complex topic that requires the knowledge of the material behaviour in the processing conditions selected for this forming process. During the rheological characterization of multi-base colloidal propellants (nitrocellulose gels), certain mechanisms, such as apparent wall slip and loss of solvents, provoke a significant distortion on the rheological

This paper proposes a heuristic and genetic approach for cutting sheet metal parts that identify effective locations for micro-joints, thereby generating an optimized tool path. In the current industrial practice of Laser, Plasma and Abrasive Water Jet (AWJ) processes, one or more micro-joints (also known as a stitch) are used to link the cut parts with the sheet. These micro-joints are randomly given

In order to improve the roundness of continuously variable wall conical rotatory parts, this paper aims to achieve precision forming of such sheet-metal casing part. The true stress-strain equation of GH3030 superalloy at normal temperature is established by experimental methods. On this basis, a power spinning finite element model about GH3030 superalloy continuously variable wall conical rotatory

The mechanical behavior of zinc alloys drastically depends on strain rate and temperature, which are not constant during forming processes. During the production of zinc sheets, the slight variations of the industrial equipment parameters induce different local thermomechanical conditions. These variations could be stemming from a non-homogeneous cooling during rolling process, or local segregation

The present study helps in providing a systematic approach towards the investigation of deep drawing and stretch forming processes for Inconel 625 alloy. Firstly, the flow stress nature and material properties of Inconel 625 super-alloy have been investigated and it has been found that temperature and deformation rate significantly affects the flow stress behavior. By using experimental flow stress

Formability predictions of Ti6Al4V titanium alloy sheets deformed at room temperature and 600 °C, using D-Bressan’s shear stress rupture criterion and the critical strain gradient macroscopic modelling are presented and discussed in relation to limit strain results obtained experimentally. Ti6Al4V Forming Limit Strain Curves were predicted and compared with experimental curves at 25 °C and 600 °C and

Abstract Voids occurred after the manufacturing process are a common defect of composite materials. They appear to have a negative impact on the matrix-dominated material properties, the gravity of which depends upon the porosity content, the shape and the volume of pores. In the present work, the effects of porosity on the shear mechanical properties of unidirectional carbon fiber-reinforced plastic

Abstract Self-reinforced polypropylene (SRPP) is a composite in which the reinforcement and the matrix consist of the same polymer, namely polypropylene. The present work focuses on the development and experimental validation of an FE model for thermoforming of SRPP. The constitutive model of SRPP sheet is based on the Boisse – Charmetant hyperelastic law. Material properties required to fit the model

Abstract This paper investigates the manufacture of biaxial carbon fiber braids and the influence that different machine settings have on variability of the textile architecture produced. In parallel, numerical simulations of the braiding process with these different machine settings have been conducted. For these studies yarn tension and process speed are varied to generate cylindrical biaxial braids

Full range constant strain rate tests are required for accurately characterizing initial yield point, strength differential effect and direct identification of constitutive laws describing the plastic behavior of materials. These tests require the use of a closed-loop control in order to achieve the constant strain rate, however this feature is not available in many laboratories. A method for full

Abstract The limited capability to predict material failure in composite materials and specifically in wavy composite layers has led to high margins of safety for the design of composite structures. Thus, the full lightweight potential of this class of materials is left unused. To understand the complex failure behavior of composite materials containing out-of-plane fiber waviness under compressive

Abstract Finite element modeling of machining aims for guidance in the choice of the cutting parameters and for the comprehension of the involved phenomena. The modeling of the behavior of the machined material is a key parameter to develop a realistic model. It is nowadays still extremely difficult to acquire experimental data on the material flow stress due to the extreme conditions encountered during

Abstract The texture evolution of copper tube manufactured by floating plug drawing process was investigated by Electron Backscatter Diffraction techniques and Visco-Plastic Self-consistent (VPSC) modelling method. The results obtained from experimentation indicate that the initial textures of copper tube transformed sharply after the first pass of the drawing process, and the final textures in the

Processing tubes from poly (l-lactic acid) (PLLA) by stretch blow moulding (SBM) is used in the manufacture of bioresorbable vascular scaffolds (BVS) to improve their mechanical performance. To better understand this processing technique, a novel experimental setup by free stretch blow inside a water bath was developed to visualise the tube forming process and analyse the deformation behaviour. PLLA

Abstract Incremental sheet-bulk metal forming (iSBMF) enables the manufacture of functional lightweight components featuring a load-adapted shape with a high material efficiency. The flexibility of the incremental forming process allows for the modification of the strain path through the adjustment of the tool motion while maintaining the final product geometry. These modifications generate both a

The paper presents the analysis of hot deformation behavior of Ti-6Al-2Sn-4Zr-6Mo (Ti-6246) alloy using the theory of dynamic material modeling (DMM) based on hot compression tests performed to a total true strain of 1 at the strain rates from 0.01 to 100 s−1 and at the temperatures within the range between 800 and 1100 °C. The processing maps according to the Prasad’s criterion were developed. The

Abstract It is worthy to investigate how it will affect the parameters calibration using an average stress state variable before the practical application of a ductile fracture criterion. In order to study this problem, ten notch specimens of AA7075-T6 sheet were designed to implement the tension tests and a parallel simulation of each test was run to obtain the variation of related variables such

In the original publication of this paper, an incorrect image of Figure 3 was used in error.

Abstract Large components, for instance in the energy industry, mining and heavy machinery, are produced from high weight cast as ingots followed by open-die forging. Besides achieving a certain final geometry and microstructure, one of the main objectives during the forging process is the elimination of casting defects, like voids from the solidification shrinkage. This process is divided in the two

Additive manufacturing is the more and more considered in industry, however efficient simulation tools able to perform accurate predictions are still quite limited. The main difficulties for an efficient simulation are related to the multiple scales, the multiple and complex physics involved, as well as the strong dependency on the process trajectory. This paper aims at proposing a simplified parametric

Abstract A numerical methodology is proposed to predict void content and evolution during autoclave processing of thermoset prepregs. Starting with the initial prepreg void content, the void evolution model implements mechanisms for void compaction under the effect of the applied pressure, including Ideal Gas law compaction, and squeeze flow for single curvature geometries. Pressure variability in

Abstract In bubble assisted vacuum thermoforming, measuring pressure-induced mechanical strains through the stereo-digital image correlation (stereo-DIC) technique while shaping thermoplastic sheet requires consideration of an appropriate reference state of surface deformations. However, when the stereoscopic measurements can be only performed after the heating step, the correlation problem should

Abstract To simulate the behaviour of textiles, three major characteristics are important, kinematic fibre interaction, shear behaviour, and thickness changes of the fabric caused by shearing. Instead of anisotropic continuum mechanical models normally used, a macroscopic finite element coupled with an internal unit cell, made of beam elements is proposed here. The beam elements represent the yarns

Hemming is the main assembly process used for auto-body panels. Surface defects resulting from the hemming operation may significantly influence the appearance aesthetics of an automobile. The formation of surface defects can be forestalled, and the process can be optimized and compensated by the numerical simulation method during the process design stage. In this study, the hemming assembly of a fuel

Bioresorbable Vascular Scaffolds (BVS) manufactured from poly (l-lactic acid) (PLLA) offer an alternative to metal scaffolds for the treatment of coronary heart disease. One of the key steps in the manufacture of these scaffolds is the stretch blow moulding process where the PLLA is biaxially stretched above glass transition temperature (Tg), inducing biaxial orientation and thus increasing ductility