Numerical Modeling of the Hot Forming Process of Composite Materials

2019 ◽  
Author(s):  
Hao Wang ◽  
Bo Li ◽  
Zongyue Fan ◽  
Xiaobai Li
Keyword(s):  
Composite Materials ◽  
Orientation Distribution ◽  
Processing Parameters ◽  
Raw Material ◽  
Hot Forming ◽  
Forming Process ◽  
Mesh Free ◽  
Thermomechanical Simulation ◽  
Simulation Results ◽  
Strengthening Particles

Abstract We present a fully coupled thermomechanical simulation of the hot forming process of composite materials. The raw material is a mixture of resin powders, strengthening particles and reinforcing fibers. Complex material responses in the process, such as phase change (melting and polymerization) and reorientation of the fibers, determine the microstructure and the performance of the final product. A phase-aware incremental mesh-free Lagrangian method is presented to overcome the challenges, which combines the Optimal Transportation Meshfree (OTM) method and the variational thermomechanical constitutive updates, and simulation results including the compression ratio, material properties of the final product and orientation distribution of fibers are recorded. By comparing the simulation results with the experimental measurements, the computational framework is validated, which enables robust and efficient analysis of the sensitivity of the performance of composite materials on their processing parameters.

Effect of Dies Temperature on Mechanical Properties of Hot Stamping Square-Cup Part for Ultra High Strength Steel

2010 ◽  
Vol 129-131 ◽  
pp. 390-394
Author(s):  
Cheng Xi Lei ◽  
Zhong Wen Xing ◽  
Hong Ya Fu
Keyword(s):  
Mechanical Properties ◽  
Numerical Simulation ◽  
Hot Stamping ◽  
High Strength ◽  
Hot Forming ◽  
Forming Process ◽  
Stamping Process ◽  
Ultra High Strength Steel ◽  
Mechanical Properties Testing ◽  
Simulation Results

The numerical simulation of hot-stamping process was carried out for UHSS square-cup parts, and the influence of dies temperature on the hot-stamping process was anlysised. Besides, through the microstructure analysis and mechanical properties testing of the formed parts, effects of dies temperature on microstructures and mechanical properties of hot-stamping square-cup parts were obtained. The experiment and simulation results showed that the mechanical properties of the UHSS are strongly dependent on the temperature, so the dies temperature is one of the most important parameters that have to be taken into account in designing the hot-forming dies and the hot-forming process.

Numerical Simulation of Cold Extrusion Process of the ZA Alloy Car Sleeve Based on LS-DYNA

2013 ◽  
Vol 411-414 ◽  
pp. 3056-3059
Author(s):  
Zhi Qiang Li ◽  
Han Xun Lv ◽  
Bing Dong Liu ◽  
Zhang Yi Yu
Keyword(s):  
Equivalent Stress ◽  
Equivalent Plastic Strain ◽  
Processing Parameters ◽  
Extrusion Process ◽  
Raw Material ◽  
Cold Extrusion ◽  
Forming Process ◽  
Contrastive Study ◽  
Finite Element Technology ◽  
Extrusion Technology

In order to increase the useful life of sleeve, improve the organizational structure and reduce costs, ZA alloy materials can be used as a raw material using cold extrusion technology for production. The main content of this paper is simulating the change rules of the equivalent plastic strain, the equivalent stress and the flow in the forming process of ZA alloy in different extrusion speed and friction coefficient condition by finite element technology, making a contrastive study with the extrusion theory, and finding out the most appropriate extrusion processing parameters. The results not only provide sufficient theatrical support for the cold extrusion process of sleeve of ZA alloy, but also offer some new thoughts for the design of extrusion mold.

A Mathmatical Approach for Modeling Real Hot Forming Process Using Physical Simulation Results

2008 ◽  
Vol 575-578 ◽  
pp. 502-507
Author(s):  
Shi Hong Zhang ◽  
Hong Wu Song ◽  
Ming Cheng ◽  
Zhong Tang Wang
Keyword(s):  
Material Flow ◽  
Physical Simulation ◽  
Differential Forms ◽  
Hot Forming ◽  
Deformation History ◽  
Forming Process ◽  
Dynamical Recrystallization ◽  
Simulation Results ◽  
Incremental Step ◽  
Simulation Condition

Recently, physical simulation has played a more and more important role in modeling hot forming process. However, difficulty still existed in simulating real hot forming process using physical simulation results directly for obvious difference in deformation history between physical simulation condition and real hot forming process. In this work, difference between physical simulation and real hot forming process was discussed and a mathmatical approach was proposed to model real hot forming process using physical simulation results. The main consideration of the method was to put physical simulation results into differential forms in order to take count in the contribution of deformation history (temperature and strain rate) at each incremental step. For the application of the approach, modeling of material flow stress, dynamical recrystallization including critical condition and recrystallziaton fraction, damage evolution and fracture criteria during real hot forming process were presented as examples, although experimental support was still needed for validation and further application.

Continuous Cooling Transformation Diagram and Properties of Hot Forming Steel

2012 ◽  
Vol 152-154 ◽  
pp. 585-588 ◽  
Author(s):  
Mei Zhang ◽  
Qing Shan Li ◽  
Kun Han ◽  
Chao Bin Huang ◽  
Ru Yi Wu ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Heating Temperature ◽  
Tensile Tests ◽  
Processing Parameters ◽  
Total Elongation ◽  
Hot Forming ◽  
Forming Process ◽  
Continuous Cooling Transformation ◽  
Continuous Cooling ◽  
Metallographic Observation

Continuous cooling transformation (CCT) diagram of steel 22MnB5 was studied using dilatometer method. The influence of the hot forming process parameters, such as the heating temperature and holding time on the mechanical properties and microstructure of stamped parts was analyzed by tensile tests and the metallographic observation on the parts with various processing parameters. The microstructural evolution obtained from the dilatometer samples reveals that the cooling rates not smaller than 20K/s induced fully martensitic microstructure. As the cooling rate decreasing, more ferrite and pearlite or more bainitic microstructure forms. Tensile tests results show an excellent tensile strength and ductility combination of 22MnB5. The tensile strength and yield strength reach 1500MPa and 1200MPa respectively, with total elongation of around 10%.

Investigation of the mechanical and forming behaviour of 3D warp interlock carbon woven fabrics for complex shape of composite material

2021 ◽  
pp. 152808372098410
Author(s):  
Mehmet Korkmaz ◽  
Ayşe Okur ◽  
Ahmad Rashed Labanieh ◽  
François Boussu
Keyword(s):  
Composite Materials ◽  
Complex Shape ◽  
Impact Damage ◽  
Woven Fabrics ◽  
Forming Process ◽  
Warp Yarn ◽  
Delamination Resistance ◽  
Fabric Architecture ◽  
Weave Pattern ◽  
Carbon Fabrics

Composite materials which are reinforced with 3D warp interlock fabrics have outstanding mechanical properties such as higher delamination resistance, ballistic damage resistance and impact damage tolerance by means of their improved structural properties. Textile reinforcements are exposed to large deformations in the production stage of composite materials which have complex shape. Although good formability properties of 3D warp interlock fabrics in forming process were already proven by recent studies, further information is needed to elucidate forming behaviours of multi-layer fabrics which is produced with high stiffness yarns like carbon. In this study, 3D warp interlock carbon fabrics were produced on a prototype weaving loom and the same carbon yarn was used in two fabric directions with equal number of yarn densities. Fabrics were differentiated with regard to the presence of stuffer warp yarn, weave pattern and parameters of binding warp yarn which are angle and depth. Therefore, the effect of fabric architecture on the mechanical and formability properties of 3D warp interlock carbon fabrics could be clarified. Three different breaking behaviours of fabrics were detected and they were correlated with crimp percentages of yarn groups. In addition, the bending and shear deformations were analysed in view of parameters of fabric architectures. Two distinct forming behaviours of fabrics were determined according to the distribution of deformation areas on fabrics. Moreover, the optimal structure was identified for forming process considering the fabric architecture.

scholarly journals Factors Affecting the Metal Recovery Yield during Induction Melting of Aluminium Swarf

2012 ◽  
Vol 730-732 ◽  
pp. 781-786
Author(s):  
Hélder Puga ◽  
Joaquim Barbosa ◽  
Carlos Silva Ribeiro
Keyword(s):  
Processing Parameters ◽  
High Energy ◽  
Metal Recovery ◽  
Raw Material ◽  
Protective Atmosphere ◽  
Induction Melting ◽  
Recovery Rates ◽  
Recovery Yield ◽  
High Efficient ◽  
Machining Operations

Machining operations of cast parts usually generate considerable amounts of waste in the form of chips (usually 3–5% of the casting weight). Traditionally, swarf is sold to scrapers and remelters, but this option is quite expensive because the selling price is roughly 30% of the acquisition price of the commercial 2nd melt raw material. For most aluminium foundries that incorporate machining operations in their products, reusing aluminium chips as raw material for the melting stocks is perhaps the best option as waste management policy in what concerns to economical and technical aspects. Nevertheless, aluminium swarf is a low density product (0.25 kg/dm3) and is usually covered by a thin film of aluminium oxide and machining fluid. Melting such a product without suitable previous preparation leads to very low metal recovery rates, high energy consumption, gases and smoke generation and very low quality of the final product. During the last years, the authors have developed a high efficient and environmentally friend aluminium swarf recycling technique, using direct incorporation in aluminium melts. The influence of processing parameters, namely melt temperature and holding time, melting atmosphere, swarf briquetting pressure and melting charge composition in the metal recovery yield and dross generation was studied and characterized, and the optimal processing parameters were established. The microstructure of the final product obtained in those conditions was evaluated and is also presented. It is shown that the recycling efficiency depends on the swarf conditioning, the melting technique and the melt treatment methodology. Swarf moisture reduction, induction melting under protective atmosphere and a specially developed degassing technique were found the most important factors influencing the recycling process. By using the developed technique, cast ingots with microstructure and sanity similar to commercially available AlSi12Cu1 2nd melt raw material were successfully obtained with minimal dross formation and metal recovery rates around 90%, without using traditional salts and fluxes.

Study of the Strain Rate Effect on Cold-Reduced Carbon Steel and Aluminium Alloy with Numerical Simulations

2006 ◽  
Vol 532-533 ◽  
pp. 973-976
Author(s):  
Lin Wang ◽  
Tai Chiu Lee ◽  
Luen Chow Chan
Keyword(s):  
Carbon Steel ◽  
Strain Rate ◽  
Strain Path ◽  
Plastic Material ◽  
Strain Rate Effect ◽  
Rate Effect ◽  
Forming Process ◽  
Risk Area ◽  
Sensitive Material ◽  
Simulation Results

In this paper, the effect of strain rate has been considered in the simulation of forming process with a simple form combined into the material law. Quite a few researchers have proposed various hardening laws and strain rate functions to describe the material tensile curve. In this study, the strain rate model Cowper-Symonds is used with anisotropic elasto-plastic material law in the simulation process. The strain path evolution of certain elements, when the strain rate is considered and not, is compared. Two sheet materials, Cold-reduced Carbon Steel (SPCC) JIS G3141 and Aluminum alloy 6112 are used in this study. Two yield criteria, Hill 48 and Hill 90, are applied respectively to improve the accuracy of simulation result. They show different performance when strain rate effect is considered. Strain path of the elements in the fracture risk area of SPCC (JIS G3141) varies much when the strain rate material law is used. There is only little difference of the strain distribution of Al 6112 when the strain rate effect is included and excluded in the material law. The simulation results of material SPCC under two conditions indicate that the strain rate should be considered if the material is the rate-sensitive material, which provides more accurate simulation results.

Recycling Waste Wood of Construction

2016 ◽  
Vol 871 ◽  
pp. 126-131 ◽  
Author(s):  
Larisa Grigorieva ◽  
Pavel Oleinik
Keyword(s):  
Composite Materials ◽  
Polymer Composite ◽  
Wood Waste ◽  
Raw Material ◽  
Polymer Composite Materials ◽  
Comparative Characteristic ◽  
Complicated Shape ◽  
Waste Wood ◽  
Wood Polymer ◽  
Wood Polymer Composite

The article considers contemporary methods and especially recycling of wood waste. The volume of wood waste is constantly growing due to the increase in the number of buildings subject to demolition or dismantling, reconstruction and repair works. The article contains the main requirements to the raw material derived from waste. Advantages of products made from wood-polymer composite materials on physic mechanical parameters. The comparative characteristic of cost for the production of wood-polymer plastic. It is noted that production made from wood polymer composite materials has unlimited product range, including boards, various profiled molded and moulded details with complicated shape (the board for the floor, skirting board, baguette, etc).

Optimization of built-part distortion in laser powder bed fusion processing of Inconel 718

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
You-Cheng Chang ◽  
Hong-Chuong Tran ◽  
Yu-Lung Lo
Keyword(s):  
Cooling Rate ◽  
Cantilever Beam ◽  
Laser Power ◽  
Scanning Speed ◽  
Processing Parameters ◽  
Laser Powder Bed Fusion ◽  
Simulation Framework ◽  
Content Type ◽  
Powder Bed ◽  
Simulation Results

Purpose Laser powder bed fusion (LPBF) provides the means to produce unique components with almost no restriction on geometry in an extremely short time. However, the high-temperature gradient and high cooling rate produced during the fabrication process result in residual stress, which may prompt part warpage, cracks or even baseplate separation. Accordingly, an appropriate selection of the LPBF processing parameters is essential to ensure the quality of the built part. This study, thus, aims to develop an integrated simulation framework consisting of a single-track heat transfer model and a modified inherent shrinkage method model for predicting the curvature of an Inconel 718 cantilever beam produced using the LPBF process. Design/methodology/approach The simulation results for the curvature of the cantilever beam are calibrated via a comparison with the experimental observations. It is shown that the calibration factor required to drive the simulation results toward the experimental measurements has the same value for all settings of the laser power and scanning speed. Representative combinations of the laser power and scanning speed are, thus, chosen using the circle packing design method and supplied as inputs to the validated simulation framework to predict the corresponding cantilever beam curvature and density. The simulation results are then used to train artificial neural network models to predict the curvature and solid cooling rate of the cantilever beam for any combination of the laser power and scanning speed within the input design space. The resulting processing maps are screened in accordance with three quality criteria, namely, the part density, the radius of curvature and the solid cooling rate, to determine the optimal processing parameters for the LPBF process. Findings It is shown that the parameters lying within the optimal region of the processing map reduce the curvature of the cantilever beam by 17.9% and improve the density by as much as 99.97%. Originality/value The present study proposes a computational framework, which could find the parameters that not only yield the lowest distortion but also produce fully dense components in the LPBF process.

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