Deformable 3D Research Articles

Study about the chip formation in the turning process using the finite element analysis

At this time, there is a significant interest in the chip shape and formation at the international level, an issue studied based on mathematical calculations, experiments, and finite element analysis. The analysis of the chip formation process showed that the thickness of the undetached chip also varies according to the rake angle of the cutting tool, and using 3D models to analyze the chip formation process demonstrates this fact. Following the research, a study was conducted in which an analysis of the chip morphology is presented. Using Deform 2D application, a finite element simulation - a comparative analysis of the chip formation was performed when the value of the clearance angle varies. The increasing variety of cutting radius values has an influence on the way the chips are formed in terms of thickness, which generate differences in its shape. Following the study, a series of conclusions and own findings emerged that with the increase of the cutting-edge radius, the stress distribution is radial over a greater area of the part, reason for which the deformation of the chip is smaller. Arguments have also been made on distribution of the temperature, which is directly influenced by the shape of the tool, influencing the temperature of the generated chip. The results also show that with the increase of the cutting-edge radius of the tool, there is a tendency for the detached chip to settle.

Development and implementation of crater and flank tool wear model for hard turning simulations

This paper concerns the tool wear in hard turning of AISI 52100 hardened steel by means of PCBN tools. The purposes of this work are the development of a tool wear model and its implementation in a FEM-based procedure for predicting crater and flank wear progression during machining operations for studying the influence of tool wear on the process in terms of tool geometry modifications and stress variation on the tool. The developed tool wear model, able to update the geometry of the worn tool as a function of the wear rate, has been implemented in the utilized Deform 2D FEM software. This new analytical model differs from the already proposed methods of existing research, since it concerns both crater and flank wear evaluation. The validation of the model has been achieved by the comparison between experimental and simulated wear parameters. For doing this, an extended experimental campaign has been accomplished. The comparison results have shown good agreement. Once validated, the FEM strategy has been utilized for examining the influence of tool wear on the effective rake angle and the related tool stresses, individuating the excessive positive rake angle value as the final tool breakage mechanism.

AN INVESTIGATION OF SURFACE ROUGHNESS ON AISI 1045 STEEL USING DEFORM 3-D AND ITS COMPARISION WITH THE EXPERIMENT

Conventional processes such as turning, and milling are often accompanied by defects such as tool marks and scratches on the final machined surface. This leads to tool wear and loss of energy which is quite undesired. This leads to poor product quality and a lowered tool life. Further, processes like honing and lapping can be used to improve the surface finish but the major drawback is the dependence on the skill of the workers involved. To overcome these issues, the burnishing operation is used for an adequate surface finish on the machined surface. The process is not only simple in operation but also chip less. In the current research work, turning operation is carried out on the ferrous material using an insert tipped tool in a CNC lathe machine. The operations are carried out at different machining parameters like speed, feed and depth of cut etc. Roughness patterns at various machining conditions are obtained and analysis was done to get the adequate machining parameters. The metal cutting process is analyzed with the FEM model for 3D simulation of the operation undertaken with a solid SPCT (single point cutting tool). This tool is modelled with CATIAV5, and exported STL files and imported in DEFORM 3D.

Assessment of stress-strain constitutive models and failure models on the shock tube based impact forming of AA 5052-H32 sheet

The present study focuses on the numerical and experimental investigation of the shock tube based forming of AA 5052-H32 sheet using a rigid nylon striker. During the shock tube impact forming, the pressure developed and the velocity of the striker are modelled in two stages, i.e., incorporating pressure in the first stage and striker displacement in the second stage during finite element simulation using DEFORM 3D. The main aim of this study is to understand the effect of different flow stress models and failure models on the forming outputs such as dome height, velocity of the sheet, effective strain distribution, and failure modes. A new strategy is followed to evaluate the rate-dependent mechanical properties by the tensile test of the sheet deformed using the shock tube. The forming outputs predicted by incorporating these properties have an acceptable agreement with the experimental data. Out of all flow stress models, modified Johnson-Cook model shows better flow stress predictability because of the inclusion of nonlinear strain rate sensitivity terms. The failure pattern analysis shows both Johnson-Cook model and Modified Johnson-Cook model have a fair agreement with experimental results. Failure strain and petal formation predicted by Brozzo failure model and Freudenthal failure model match acceptably with the experimental results. SEM images confirm deeper and larger parabolic dimples on the fracture surface of shock tube-based deformed sheet, indicating enhanced formability as compared to the sheet formed by quasi-static deformation.

Predication of temperature distribution and strain during FSW of dissimilar Aluminum alloys using Deform 3D

Dissimilar aluminium alloy plates AA6061 and AA5052 were subjected to friction stir welding (FSW) in order to examine the effect of heat generation on the welding process. Thermocouples were used to measure the temperature distribution on the workpiece during welding and it was found that the advancing side had higher temperatures than the receding side. The FSW process was simulated at tool speeds of 1000, 1200, and 1400 rpm, as well as feed rates of 20, 40, and 60 mm/min. The tests were designed using the Taguchi OA. AA6061 identical welds show a small reduction in grain size at the HAZ, but AA5052 and AA6061 dissimilar welds show much larger grain sizes at the weldment than the base metal. While keeping a consistent feed rate, the tool speed was found to boost weld zone heat generation. It is possible to reduce the amount of heat generated in weld zones by increasing the feed rate while maintaining consistent tool rotation rates. Analysis of variance (ANOVA) demonstrated that the advancing side, retreating side as D1F3S1, and total heat generation is D1F3S3 (i.e., distance from the welded zone is 20 mm, feed rate at 60 mm/min, and tool speed at 1000 rpm) is the ideal temperature distribution and heat generation condition. For FSW, Deform-3D software was used to create a model of the workpiece and tool. Thermal analysis was performed to determine the temperature distribution throughout each part of the workpiece.

A review on Johnson Cook material model

To design and optimise process parameters in the metal forming industry, it is necessary to have a consistent and realistic representation of material behaviour where strain, strain rate, and temperature have an effect on the material flow stress. This paper examines various approaches that are employed in calculating the Johnson Cook material constants. Split Hopkinson-bar methodology and universal tensile tests were used to determine the material constants related to Johnson Cook material and failure models. These models were used in numerical simulations to facilitate design optimization and reduce experimentation costs. Johnson Cook material models were employed in various simulation software’s like ABAQUS, LS-DYNA, and DEFORM 3D to simulate metal turning, milling, and forming operations.

Wear Behavioral Study of Hexagonal Boron Nitride and Cubic Boron Nitride‐Reinforced Aluminum MMC with Sample Analysis

During the stir casting process, different percent weights of hexagonal boron nitride (HBN) and cubic boron nitride (CBN) were mixed with aluminum alloy 6061. The test specimens are then machined from the cast aluminum metal matrix composites. The tests are carried out utilizing an ASTM G99‐compliant pin‐on‐plate tribometer on a pivoting EN32 circle. Minitab 16 is used to plan the dry sliding wear trials, which are set up in an orthogonal array. The input parameters are percent HBN addition and CBN addition, sliding speed, and load, and the wear rate was considered to be the output parameter. The actual density of the cast specimens was found to be greater than 90% of their theoretical density. The accumulation of HBN and CBN greatly enhances the wear resistance of aluminum metal matrix composites, according to research. The technique of regression analysis is utilized to establish genuine links between the wear rate and input parameters. The morphology of the worn out surfaces was examined using a scanning electron microscope (SEM). After numerous iterations, the simulation source of DEFORM 3D forecasts the stress and velocity component of the frictional surface contact area.

Grouped Spatio-Temporal Alignment Network for Video Super-Resolution

Video super-resolution based on CNNs has recently achieved significant progress. The existing popular super-resolution methods usually impose the optical flow between neighboring frames for temporal alignment. However, estimation of accurate optical flow is hard and expends greater computation. To address this problem, we propose a novel grouped spatio-temporal alignment network (GSTAN) that effectively incorporates spatio-temporal information in a hierarchical way. The input sequence is divided into several groups corresponding to different frame rates. These groups provide complementary information, which is helpful to restore missing textures for the reference frame. Specifically, each group employs deformable 3D convolution to incorporate spatio-temporal information, which avoids artifacts from explicit motion estimation. In addition, a Gated-Dconv information filter is proposed to control information flow to focus on the fine details. Finally, these groups provide complementary information, which is integrated with the inter-group fusion module. Extensive experiments have demonstrated our method achieves state-of-the-art SR performance on several benchmark datasets.

Research of temperature distribution in the process of thermo-frictional cutting of titanium alloy Ti-5553

This article presents the results of studying the temperature distribution in the process of thermo-frictional cutting of titanium alloy Ti-5553. The process was simulated using the Machining module of the DEFORM 3D software package based on the finite element method. It was found that when cutting off the titanium alloy Ti-5553, depending on the geometry of the circular saw, the temperature in the "disk-workpiece" contact zone reached T = 800 ÷ 1130 °C, and its propagation into the depth of the workpiece was 0.66 ÷ 0.96 mm. The optimal geometry of a circular saw for cutting off titanium alloy Ti-5553: L1 = 18 mm, L2 = 14 mm, v = 2 mm. The research was carried out within the framework of the grant № AP09562459.

MULTIPLE PROCESS PARAMETER OPTIMIZATION OF FORWARD EXTRUSION PROCESS ON AA 2024

Extrusion is a simple metal forming process in which a block of metal is forced through a die orifice with a certain shape under high pressure. This extrusion process is influenced by many process parameters such as die angle (DA), ram speed (RS), coefficient of friction (COF), Extrusion ratio, Die land height, work piece diameter and length, material properties etc. In extrusion process, extrusion force is crucial parameter, the flow of metal and hence the extrusion force is significantly influenced by the above parameters which results in quality of the product. The present study numerically investigates the influence of major process parameters such as die angle, ram speed, coefficient of friction on the extrusion process. The AA2024 material is chosen as work piece material and the extrusion force and damage is considered as the output responses. The input process parameters are varied in three levels (Level - 1: 10° DA, 1.6mm/min RS, 0.06 COF; Level - 2: 20° DA, 3.2mm/min RS, 0.08 COF; Level - 3: 30° DA, 4.8mm/min RS, 0.01 COF). Numerical simulations are performed by using DEFORM 3D software. The simulations are conducted as per L27 orthogonal array. From the results it is observed that Increase of die angle, ram speed and coefficient of friction increases the extrusion force. The die angle has highest (86.45%) influence on the extrusion force, then after ram speed (6.60%). The coefficient of friction has insignificant influence (0.55%). It is also noticed that the damage is considerable after the 20° die angle. A multi parameter optimization is also done by using the Grey relation analysis by considering the equal weightage of extrusion force and damage. The optimum levels of input process parameters for the minimum extrusion force and damage is DA level 1, RS level 1, and COF level 3.

Temperature and strain distribution during friction stir welding of AA6061 and AA5052 aluminum alloy using deform 3D

This study investigated the effect of heat generation during friction stir welding (FSW) on dissimilar aluminium alloy plates AA6061 and AA5052 using process variables such as tool rotational speed, feed rate and temperature distribution. Temperature distributions on the workpiece were recorded at advancing side and receding side during welding by using thermocouples and revealed that temperatures on the advancing side are greater than those on the receding side. The FSW process was simulated at the tool speed of 1000, 1200 and 1400 rpm, feed rate of 20, 40, 60 mm/min. A Taguchi OA has been used for designed the experiments. The findings of the micro hardness test at the welded zone analysed using Vickers’s tester. Microstructure analysis of AA6061 identical welds reveals that grains are slightly reduced at HAZ, while analysis of AA5052 and AA6061 dissimilar welds reveals that grain are significantly enlarged at weldment than base metal. It also found that, the tool speed increases while maintaining a steady feed rate, increased the amount of heat generated in weld zones. On the other hand, increasing feed rate while maintaining constant tool rotational speeds results in a decrease in the amount of heat created in weld zones. Analysis of variance (ANOVA) revealed, the optimal condition of temperature distribution and heat generation is T3F1 (i.e., tool speed of 1400 rpm and feed rate of 20 mm/min). A model of the workpiece and tool was developed using Deform-3D Software for friction stir welding, and thermal analysis was performed to analyse the temperature distribution.

Active yarn meshes for segmentation on X-ray computed tomography of textile composite materials at the mesoscopic scale

For the past decade, the composite material community has been struggling to bridge the gap between the X-ray tomography of fiber composites and the realistic modelling of their internal structure at the mesoscopic scale. This paper proposes a new yarn segmentation method relying on a variational approach with deformable 3D surfacic meshes representing the yarn envelopes. It requires the previous localisation of yarn centroids. We apply five forces directly applied on the mesh vertices to drive the mesh fitting towards the visible yarn edges on the tomographic volume. The five forces enable a compromise between the intrinsic aspect of the envelope and the attachment to the yarn contours and regions, while limiting inter-yarn overlap. Results are presented on a X-ray tomography of a non-crimp fabric composite with unidimensional fiber bundles and on a woven composite tomography.

FEM Analysis of Textile Reinforced Composite Materials Impact Behavior.

Composite materials reinforced with textile fabrics represent a complex subject. When explaining these materials, one must consider their mechanical behavior in general, and impact resistance in particular, as many applications are characterized by dynamic strains. Impact characteristics must be considered from the early stages of the design process in order to be controlled through structure, layer deposition and direction. Reinforcement materials are essential for the quality and behavior of composites, and textile reinforcements present a large range of advantages. It takes a good understanding of the requirements specific to an application to accurately design textile reinforcements. Currently, simulations of textile reinforcements and composites are efficient tools to forecast their behavior during both processing and use. The paper presents the steps that must be followed for modelling the impact behavior of composite materials, using finite element analysis (FEM). The FEM model built using Deform 3D software offers information concerning the behavior structure during impact. The behavior can be visualized for the structure as a whole and, for different sections, be considered significant. Furthermore, the structure’s strain can be visualized at any moment. In real impact tests, this is not possible due to the very short time interval and the impossibility to record inside the structure, as well as to record all significant stages using conventional means.

FEM analysis of manufacturing of a hollow product with an outer flange in a four-stage cold forming process

The paper presents the results of a FEM computer simulation of the cold forming process of a hollow sleeve forgings with an outer flange. Numerical simulations were carried out in DEFORM 2D / 3D. For the numerical calculations of the forming process the axisymmetric calculation module was used. As the test object, a tubular workpiece with an outer diameter of Ø50 mm and a wall thickness of 10 mm made of 42CrMo4 steel was used. The process of forming the rotary sleeve was conducted in four stages consisting of two technologies. The first stage of the research was the analysis and selection of parameters of the extrusion process, which was used for the first stage of forming. The processes of free extrusion and the use of a container were analysed. Furthermore different die angles and different wall thickness reductions were used. The products obtained in the extrusion process were upset in three conical blanks. The aim of the study was to analyse the numerical accuracy of the designed process of forming the hollow shaft with flange. The analysis of the results was based on the deformation intensity distribution maps, the Cockroft-Latham criterion distribution and the progress of the forming forces. On the basis of the conducted research, it was concluded that the presented process of forging a hollow product with a flange in four stages is possible to carry out correctly.

Studies on friction behaviour of aluminium AA4032 alloy during forging using ring compression test

In metal forming, friction has a negative effect on the deformation load & energy requirements, homogeneity of metal flow, quality of formed surfaces, etc.; however, its effect can be reduced through the use of proper lubricants. Mostly, in industrial applications, selection of proper lubricant for specific material is challenging and quantification of magnitude of friction at diework piece interface is essential. Hence, for metallic alloys, a realistic friction factor is needed to be known and used at the diework piece interface for better control of deformation process. Thus, this research, generally, aims at experimental investigation of the friction behavior of aluminum AA4032 alloy and selection of suitable lubricant for its effective processing using ring compression test and finite element (FE) simulations. Meanwhile, the effect of metal surface conditions and different lubricants namely palm oil, grease, emulsion oil and dry conditions on the friction behaviour has been evaluated. A commercial FEM software, DEFORM 3D, is used to analyze the flow of metal, determine the geometry changes of the specimen and generate friction calibration curves. The results revealed that the nature of metal surface and lubricating conditions have significantly affected the metal flow pattern, deformation load requirement, induced effective stress and strain, and geometry of the metal. The friction factor at die-work piece is determined for different lubricating conditions. Among lubricants employed, palm oil is found to be suitable and effective for industrial processing of aluminium AA4032 alloy, specifically for forging. The FE simulation results are in a good agreement with the experimental one.

Anatomically constrained deformable 3D reconstruction of intraoperative uterus from preoperative MRI data on uterine fibroid treatment

ABSTRACT Detections of the uterus using preoperative magnetic resonance imaging (MRI) data are required for intraoperative navigation in High-Intensity Focused Ultrasound (HIFU) treatment of uterine fibroids. The modelling of the intraoperative uterus between empty and full bladder anatomy deems to be a crucial step to quantify uterus deformation caused by the bladder-and-rectum-filling (BRF) technique. In this paper, a novel two-stage conditional generative adversarial network (cGAN) is proposed to perform intraoperative uterus deformable reconstruction with anatomical constraints using only single preoperative MRI data, viz. ACDeformRec. The highly constrained anatomy properties are further captured by a novel attention network that formulates high-level uterus segmentation task by incorporating correlations of surrounding organs for more anatomically plausible reconstruction. The experimental result demonstrates the robustness of ACDeformRec by evaluating its performance on 181 clinical datasets and has achieved the lowest reconstruction error of 0.735 ± 0.045 mm with Dice Similarity Coefficient of 94.23% and Normalised Cross Correlation of 97.23%.

Application of Numerical Simulation and Physical Modeling for Verifying a Cold Forging Process for Rotary Sleeves

This paper presents the modeling of a cold forging process for a rotary sleeve. The process of forging a EN 42CrMo4 steel part was first modeled numerically by the finite element method using simulation software DEFORM 3D ver. 11.0. After that, the developed forging process was verified by experimental tests carried out in laboratory conditions with the use of 1:2 scale tools and a material model of aluminum alloy EN AW-6060. Finite element method (FEM) results demonstrated that rotary sleeves could be formed from tubes by cold forging. Results of the experimental tests showed, however, that the material inside the hole of the work piece might not adhere to the surface of the sizing pin. Distributions of strain and stress during the forging process are determined. Geometrical parameters of forged parts obtained in experimental tests are compliant with the dimensions of forged parts simulated by FEM. In addition, experimental forces of the forging process show a high agreement with the forces obtained in FEM simulations.

Multi-Response Optimization of cutting parameters in MQL assisted Turning of Haynes 25 alloy with Taguchi based Grey Relational Analysis

Haynes 25 is a cobalt based superalloy gaining its importance in aerospace, heat treatment applications, chemical handling equipment, commercial gas turbine engines, bearing material, etc. This alloy is featured with low thermal conductivity, wear and corrosion resistance, strength with good resistance to oxidation at high temperatures. In the present study, optimization of process parameters in turning Haynes 25 alloy with uncoated and coated carbide tools under the minimum quantity lubrication (MQL) using Taguchi based grey relational analysis (GRA) method is attempted. The influence of cutting parameters and nano-particle concentration on surface roughness, tool wear, cutting and thrust forces are analyzed to improve the alloy machinability. The work also compares the responses obtained with uncoated and coated tool inserts and analyzes the effect of nano-particle concentration. Further, the experimental cutting and thrust forces are computed and validated using FE based DEFORM 3D software. The results obtained through simulation are in good accordance with experimental data within an average relative error of about 12 %.

A stable node-based smoothed PFEM for solving geotechnical large deformation 2D problems

The strain smoothed nodal integration particle finite element method (NS-PFEM) has a high level of computational efficiency. However, it suffers from the ‘overly soft’ problem. This study presents the development of a stable nodal integration PFEM for solving geotechnical large deformation problems. A node-based strain smoothing (SNS) PFEM is developed by combining a 3-node triangular element-based PFEM and a stable nodal integration method with strain gradient in the smooth domain for single solid phase. Its performance is examined by simulating two benchmark tests on elastic material (i.e., cantilever beam and infinite plate with a circular hole) and three cases on elastoplastic material (i.e., cavity expansion, penetration of a rigid footing in soft soil and progressive failure of slope). Results show that the integration of stabilisation term gives the SNS-PFEM ‘close to exact’ stiffness, thereby resolving the ‘overly soft’ and temporal instability issues seen with the NS-PFEM. The proposed method is powerful and easily extensible for analysing large deformation problems in geotechnical engineering.

Deformable registration of lateral cephalogram and cone-beam computed tomography image.

This study aimed to design and evaluate a novel method for the registration of 2D lateral cephalograms and 3D craniofacial cone-beam computed tomography (CBCT) images, providing patient-specific 3D structures from a 2D lateral cephalogram without additional radiationexposure. We developed a cross-modal deformable registration model based on a deep convolutional neural network. Our approach took advantage of a low-dimensional deformation field encoding and an iterative feedback scheme to infer coarse-to-fine volumetric deformations. In particular, we constructed a statistical subspace of deformation fields and parameterized the nonlinear mapping function from an image pair, consisting of the target 2D lateral cephalogram and the reference volumetric CBCT, to a latent encoding of the deformation field. Instead of the one-shot registration by the learned mapping function, a feedback scheme was introduced to progressively update the reference volumetric image and to infer coarse-to-fine deformations fields, accounting for the shape variations of anatomical structures. A total of 220 clinically obtained CBCTs were used to train and validate the proposed model, among which 120 CBCTs were used to generate a training dataset with 24k paired synthetic lateral cephalograms and CBCTs. The proposed approach was evaluated on the deformable 2D-3D registration of clinically obtained lateral cephalograms and CBCTs from growing and adult orthodonticpatients. Strong structural consistencies were observed between the deformed CBCT and the target lateral cephalogram in all criteria. The proposed method achieved state-of-the-art performances with the mean contour deviation of 0.41 0.12 mm on the anterior cranial base, 0.48 0.17 mm on the mandible, and 0.35 0.08 mm on the maxilla, respectively. The mean surface mesh ranged from 0.78 to 0.97 mm on various craniofacial structures, and the LREs ranged from 0.83 to 1.24 mm on the growing datasets regarding 14 landmarks. The proposed iterative feedback scheme handled the structural details and improved the registration. The resultant deformed volumetric image was consistent with the target lateral cephalogram in both 2D projective planes and 3D volumetric space regarding the multicategory craniofacialstructures. The results suggest that the deep learning-based 2D-3D registration model enables the deformable alignment of 2D lateral cephalograms and CBCTs and estimates patient-specific 3D craniofacial structures.