DEFORM-3D Software Research Articles

Three-dimensional finite element model of friction drilling process in hot forming processes

Friction drilling processes are used commonly in hot forming operations. This process is similar to drilling processes but without using chip. This process is used especially for joining thin-walled metal components. In this study, the drilling process using centerdrill is investigated both experimentally and numerically. The finite element analyses (FEA) were conducted using deform-3D software based on finite element method (FEM). In this study, an analytic model is developed, which calculate the process parameters as torque and axial power, heat transfer coefficient. A comparison was also made for temperature, torque and axial force obtained from experimental and numerical analyses. At the end of the study, while the torque and axial force values decrease with increasing of spindle speed, temperature values of centerdrill and workpiece increase with increasing of spindle speed. A good consistency between both experimental and FEA simulations was found during the centerdrill process.

Study of Static Recrystallization Behavior of a Nitrogen-Alloyed Ultralow Carbon Austenitic Stainless Steel by Experiment and Simulation

Static recrystallization (SRX) behavior of a nitrogen-alloyed ultralow carbon austenitic stainless steel was studied on a Gleeble-1500D thermal-simulator by two-step hot compression tests. Deformation temperatures of 1173-1473 K, deformation strains of 0.051-0.105, strain rates of 0.01-1 s−1, and inter-step times of 1-100 s were selected as the deformation conditions to investigate the effects of deformation parameters on SRX behavior. Besides, the influences of initial grain size on SRX behavior were studied. The results show that deformation temperature and strain have greater influences on SRX behavior than strain rate and initial grain size. Based on true stress-true strain data obtained from the experiments, SRX kinetics equation was determined. In addition, the established SRX kinetics equation was introduced into finite element simulation software DEFORM-3D to perform the two-step compression deformation. Furthermore, SRX kinetics equation was modified for improving the accuracy of finite element simulation, and the modified SRX kinetics equation was verified.

Finite Element Analysis of Equal Channel Angular Pressing on Densification and Deformation Behaviour of Al-1100 Processed by Powder Metallurgy Route

Background/Objectives: Pressed and sintered Al-1100 powder is subjected to Equal Channel Angular Pressing (ECAP) process to study densification and deformation behaviour under different initial relative density and shear friction conditions. Methods/Statistical Analysis: Commercially pure Aluminium (Al 1100) powder containing 99% Al, 0.05-0.2% Cu, 0.05% Mn, remainder of Si, Fe and Zn is processed through normal powder metallurgy route followed by ECAP process. Finite Element Analysis through simulations are carried out using DEFORM 2D software for different initial relative densities of 0.700, 0.750 and 0.800 under three friction coefficients of 0.05, 0.075 and 0.15. Effective stresses, strains and loads are plotted. Findings: Full densification is achieved near the inner corner of the die channel compared to the outer corner at the end of the process. Uniform densification (relative almost greater than 0.980) is achieved in the middle portion of the specimen. As the friction is increased load required also increases. Formation of dead zone near the inner corner of the die channel reduces as the initial relative density is increased from 0.700 to 0.800. With higher initial relative density, complete densification occurs in the lower friction conditions like close to 0.05 shear friction coefficient. Effective stress is higher in the plane of intersection of the die channels where the actual deformation occurs. With the increase in initial relative density, effective strain also increases along the length of the specimen whose value is higher near the top portion of the die channel as compared to the bottom portion. Application/Improvements: ECAP eliminates residual porosity. Ultra fine grained structures are produced, even finer (better mechanical properties) than that by ECAP of cast products. Best suited for aerospace, defence and biomedical applications.

New Optimum Extrusion Parameters of 9% Cr Ferritic Steel Tubes

The mechanism of austenite grain growth prior to forging of 9% Cr ferritic steels was analyzed. Pre-forging heating temperature and holding time had an obvious effect on austenite grain size and delta ferrite morphology. Hot compression experiments were conducted by using a Gleeble 1500D thermal–mechanical simulator. A hot upsetting test was performed on an HP01-500 oil press to verify the geometric dynamic recrystallization mechanism. New extrusion technology parameters of steel tubes were optimized by the Deform 2D software, and practical tests were conducted. Results indicated that the grains grew slowly at low temperatures (i.e., 1000°C and 1050°C). The kinetic curve of grain growth was close to the “S” type at 1100°C. The grains exhibited abnormal grain growth at high temperatures (i.e., 1150°C and 1200°C). The quantity of delta ferrites markedly increased at 1250°C. In addition, grains were refined by geometric dynamic recrystallization during the formation process. Mechanical properties of 9% Cr tube met standard requirements.

Three-dimensional finite element model of the drilling process used for fixation of Salter–Harris type-3 fractures by using a K-wire

Abstract. In this study, the drilling process was performed with Kirschner wire (K-wire) for stabilization after reduction of Salter–Harris (SH) type-3 epiphyseal fractures of distal femur. The study was investigated both experimentally and numerically. The numerical analyses were performed with finite element method (FEM), using DEFORM-3D software. Some conditions such as friction, material model and load and boundary must be identified exactly while using FEM. At the same time, an analytic model and software were developed, which calculate the process parameters such as drilling power and thrust power, heat transfer coefficients and friction coefficient between tool–chip interface in order to identify the temperature distributions occurring in the K-wire and bone model (Keklikoǧlu Plastik San.) material during the drilling process. Experimental results and analysis results have been found as consistent with each other. The main cutting force, thrust force, bone model temperature and K-wire temperature were measured as 80° N, 120° N, 69 °C and 61 °C for 400 rpm in experimental studies. The main cutting force, thrust force, bone model temperature and K-wire temperature were measured as 65° N, 87° N, 91 °C and 82 °C for 800 rpm in experimental studies. The main cutting force, thrust force, bone model temperature and K-wire temperature were measured as 85° N, 127° N, 72 °C and 67 °C for 400 rpm in analysis studies. The main cutting force, thrust force, bone model temperature and K-wire temperature were measured as 69° N, 98° N, 83 °C and 76 °C for 800 rpm in analysis studies. A good consistency was obtained between experimental results and finite element analysis (FEA) results. This proved the validity of the software and finite element model. Thus, this model can be used reliably in such drilling processes.

Microstructural simulation of friction stir welding using a cellular automaton method: a microstructure prediction of AZ91 magnesium alloy

Recently, some researchers have simulated FSW using FEM and studied the influence of process parameters and tool geometry on material flow, welding force, and temperature and strain distributions during friction stir processing. Additionally, in terms of microstructure modeling, various approaches such as the Cellular Automaton (CA) model have been developed to simulate microstructural evolution during plastic deformation processes. In this work, a finite element model (FEM) is established to study the microstructure evolution during friction stir welding (FSW) of AZ91 magnesium alloy. To this aim, first, the hot compression tests at different temperatures and strain rates were carried out to achieve the flow stress curves. Then, the hardening parameter, the recovery parameter and the strain rate sensitivity were calculated according to flow stress results and using the Kocks−Mecking model. Next, a continuum based thermo-mechanically coupled rigid-viscoplastic FEM model was proposed in Deform-3D software to simulate the FSW of AZ91 magnesium alloy. To evaluate microstructure of the weld zone a model is proposed based on the combination of Cellular Automaton and Laasraoui-Jonas models. Temperature history, strain distribution and welding force are achieved through thermomechanical model and microstructure and grain size distribution are achieved by microstructure evolution model. The effects of rotational and traverse speeds on the grain size and microstructure of weld zone are considered. There is a good agreement between results of numerical models and experiments in the aspects of welding forces, temperature history and grain size. Additionally, the proposed microstructure evolution model can simulate accurately the dynamic recrystallization (DRX) process during FSW and its resulted microstructure.

Upper-bound and finite element analyses of multi-row sprocket during cold semi-precision forging process

The cold semi-precision forging of a multi-row sprocket was investigated using upper-bound (UB) and finite element methods combined with experiments. Based on the design of a new tooth profile for the sprocket, a cold semi-precision forging process and a kinematically admissible velocity field for filling the die cavity were proposed. Using the UB method, the velocity fields of the sprocket billet in the forming process were divided theoretically and calculated. The process of forging a multi-row sprocket was simulated using the FEM package Deform-3D V6.1 to obtain the distributions of the velocity field and the effective stress field in filling the die cavity. Similar to the simulated results, the experiment on cold forging a 5052 aluminum alloy sprocket was successfully performed. By comparing the calculated (UB method), experimental and simulated load-stroke curves, the calculated and simulated results were basically in accordance with the experimental results. The study provides a theoretical foundation for the development of the precision forging of multi-row sprockets.

Effect of micro-textured tools on machining of Ti–6Al–4V alloy: An experimental and numerical approach

In this work, an attempt is made to reduce the detrimental effects that occurred during machining of Ti–6Al–4V by employing surface textures on the rake faces of the cutting tools. Numerical simulation of machining of Ti–6Al–4V alloy with surface textured tools was employed, taking the work piece as elasto-plastic material and the tool as rigid body. Deform 3D software with updated Lagrangian formulation was used for numerical simulation of machining process. Coupled thermo-mechanical analysis was carried out using Johnson-cook material model to predict the temperature distribution, machining forces, tool wear and chip morphology during machining. Turning experiments on Ti–6Al–4V alloy were carried out using surface textured tungsten carbide tools with micro-scaled grooves in preferred orientation such as, parallel, perpendicular and cross pattern to that of chip flow. A mixture of molybdenum disulfide with SAE 40 oil (80:20) was used as semi-solid lubricant during machining process. Temperature distribution at tool–chip interface was measured using an infrared thermal imager camera. Feed, thrust and cutting forces were measured by a three component-dynamometer. Tool wear and chip morphology were captured and analyzed using optical microscopic images. Experimental results such as cutting temperature, machining forces and chip morphology were used for validating numerical simulation results. Cutting tools with surface textures produced in a direction perpendicular to that of chip flow exhibit a larger reduction in cutting force, temperature generation and reduced tool wear.

Simulation of dynamic recrystallization process during friction stir welding of AZ91 magnesium alloy

In the present research, a continuum-based thermo-mechanically coupled rigid-viscoplastic finite element model is proposed in Deform-3D software to simulate the friction stir welding (FSW) of AZ91 magnesium alloy. Then, to consider the microstructure evolution of the weld zone, a model is established based on the combination of cellular automaton and Laasraoui-Jonas models. The simulated microstructure of the weld zone is compared with the experiment one. Furthermore, the ability of presented model in demonstrating the nucleation and grain growth stages during dynamic recrystallization (DRX) is considered.

Investigation of extrusion limit of Incoloy028 alloy tube by combining numerical and analytical methods

Extrusion limit is an important evaluation criterion in extrusion process design as it determines the deformation degree in each operation. In this paper, a new method for establishment of extrusion limit diagram was proposed. To do so, the constitutive equation of Incoloy028 alloy (IN028) was established by hot compression test and the tube hot extrusion process was simulated by commercial Deform-2D software. In addition, the extrusion process is also analyzed by analytical method in which the billet heating temperature, extrusion speed and ratio were considered as influence factors. The analytical results of extrusion force and demoulding temperature were obtained. The maximum extrusion pressure of 60 MN and the eutectic melting temperature of IN028 (1,350 °C) was selected as the limit of extrusion force and the permissible maximum temperature. The limit diagram for IN028 tube in hot extrusion process were generated using the analytical and numerical methods simultaneously and the extrusion limit diagram of IN028 at different ratios is thus provided.

Numerical Simulation on the Die Filling Process of the Thixo-Forging of Al-7 wt pct Si/Al-22 wt pct Si Bimetal Composite

A bimetal semi-solid fluid has more complicated flow behaviors than a normal semi-solid fluid during thixo-forging. In order to clarify the detailed properties of the bimetal thixo-forging, the effects of billet temperatures and frictions on flow behaviors of the Al-7 wt pct Si/Al-22 wt pct Si bimetal thixo-forging were investigated by commercial software DEFORM-3D. The simulation results show that shear force was unable to be transferred from the upper billet on the drop die side to the bottom billet on the counter die side efficiently in the initial stage of die filling. Only when the upper billet severely deformed, did the shear force deform the bottom billet. A stiffer upper billet can enhance the efficiency of shear force transfer. The processing temperature, the relative stiffness between the upper billet and bottom billet, and frictions between dies and billets, as well as friction between billets, were important factors to control the interface outline of the bimetal parts. The experimental results are consistent with the simulation results.

Improvement of deep drawability by using punch surfaces with microridges

Because of product miniaturization, demand for cups created by deep drawing has increased. However, because thin sheet materials exhibit poor deep drawing formability, using deep drawing on micro/meso cups is rather difficult. In this study, punch surfaces with microridges were used to enhance deep drawing formability. The concept was based on the observation that punch surfaces with microridges near the punch nose could disperse the drawing force of punches on sheet materials and delay the cracking of sheet materials. In this study, cylindrical cups composed of copper alloy were used. First, punch surfaces with microridges were designed and the Deform 2D software was used for analyzing the formability of deep drawing by using punch surfaces with and without microridges. Second, drawing dies were designed and produced, and an experiment was conducted to verify the results of the analysis. The study results indicated that commercial forming analysis software can be used to simulate the effect of microridges on deep drawability accurately. A comparison between the two punch surface types revealed that punch surfaces with microridges exhibited a slightly increased drawing force (3%) compared with those without microridges. Concurrently, the effect of punch surfaces with microridges increased forming height by at least 100%.

Unequal thickness billet design for large-scale titanium alloy rib-web components under isothermal closed-die forging

The under-filling defect is prone to occur in the forging of large-scale titanium alloy rib-web components (LTRC). A rigorous preform design with accurate volume distribution is required for a desirable LTRC. The unequal thickness billet (UTB) design divides the preform into multiple regions of varying thickness and can not only adjust the volume distribution effectively but also control forming defects with low cost and high efficiency. The purpose of this paper is to attain LTRC without any under-filling defects using the UTB methodology. Firstly, cross sections are extracted from a desirable LTRC so as to create the initial UTB according to the calculated neutral layer of material flow between ribs. Then a finite element (FE) model is established, using the Deform-3D software for the isothermal closed-die forging to study the material flow and die cavity filling. Finally, three schemes to modify the initial UTB are proposed for those areas where there is under-filling: (I) increase the number of regions in affected areas, (II) adjust the size parameters of the regions around affected areas, and (III) increase the thickness of the regions in affected areas. In conclusion, it is found that scheme I and scheme II are based on the constancy of volume principle and can be adopted if the distribution of the ribs on those affected areas is quite simple. However, scheme I increases the complexity of the UTB, so scheme II is preferred. Alternatively, if the distribution of ribs on those regions is more complicated, scheme III can be adopted. Although the volume of the UTB is increased slightly, all ribs can be completely filled, allowing the most accurate LTRC to be produced.

Finite element simulation based plate edging model for plan view pattern control during wide and heavy plate rolling

From a new viewpoint to improve plate plan view pattern during hot rolling, a plate edging process was proposed to roll back only the plate width spread of conventional rolling in this paper. Using commercial finite element (FE) analysis software DEFORM-3D, a three-dimensional rigid plastic FE model for vertical–horizontal (V–H) hot rolling was developed on the basis of a 5 m wide and heavy plate mill. Three hundred and twenty kinds of different V–H rolling processes were simulated by the FE model. Basing on the simulation results, the formation laws of dog bone shape during the vertical rolling and the width spread behaviours during the horizontal rolling were clarified. A plate edging model predicting the plate edging efficiency was established with the aid of an artificial neural network. The plate edging efficiency predicted by this plate edging model agreed well with those predicted by the existing strip edging models when the slab width/thickness ratio was small, which confirmed the validity of the plate edging model. The plate edging model expanded its application scope into the wide and heavy plate hot rolling.

Research on technology of twin rollers rotary forging of spiral bevel gears

To investigate the technology of twin rollers rotary forging of spiral bevel gears, three different models, which are the open die, the closed die and the floating die model, were designed to rotary forge a big spiral bevel gear whose external diameter is 246 mm. The effects of the spiral bevel gears that formed in the three models were analysed by three-dimensional finite element method under the commercial software DEFORM 3D. Finally, experiments have been carried out on a 20CrMnTi gear billet to compare the numerical results. The simulation results are in good agreement with the experimental ones and demonstrate that the floating die is the optimal model to rotary forge the spiral bevel gear, the microstructure of the gear that formed by rotary forging is refined well, and the microhardness reaches 457.8 HV (an increase of 110.0 HV) compared with the gear that formed by machining. These results provided a scientific basis for actual production of the spiral bevel gear.

Numerical Simulation of Extrusion of Hollow Profiles from Mg-Li Alloy

Magnesium is the lightest metal used for construction elements. Due to their lightness and good mechanical properties magnesium alloys have been used in aviation industry since 50’s of the last century. Magnesium – Lithium alloys are the lightest of all magnesium alloys. Their density can be lower than 1,0 g/cm3. In this paper the results of numerical simulation of direct extrusion of Mg-Li alloy hollow profile are presented. The alloy has 12% addition of Lithium and has been extruded through porthole dies. The analysis of temperature distribution, metal flow and stress and strain with the use of Finite Element Method (FEM) have been calculated in Deform 3D software. The mathematical simulation have been performed for various ingot temperatures and the die’s geometry. Thanks to numerical simulation, the optimal temperature and die geometry have been determined and due to this fact the optimal stress conditions in a welding chamber have been obtained

Numerical and Experimental Approach of Cutting Temperatures to Green Turning of 42CrMo4 Steel

In the present contribution, experimental and numerical methods concerning orthogonal cutting are proposed in order to study the thermal phenomena accompanying the turning process of 42MoCr4 alloyed steel with respect to cutting parameters (depth of cut, feed rate, and cutting speed), such as cooling-lubrication method. Two environment-friendly cooling techniques (near dry cutting and dry cutting) and for comparison reasons conventional flood cooling have been considered. For experimental validation, series of tests are carried out concerning cutting temperature measurement close to the cutting zone. The influence of cutting conditions on the cutting temperature has been analyzed using Design Expert software. Additionally, for the dry cutting tests, numerical simulation of thermal phenomenon have been performed using DEFORM 2D software. Comparison of numerical results concerning cutting temperature to experimental ones shows a very good coincidence.

Analysis of Stress and Strain on Shaft Parts for Closed Type of Cross Wedge Rolling during Stretching Stage

To improve the quality of shafts parts end in cross wedge rolling, this paper applied closed type of cross wedge rolling technology to form shaft parts. By using finite element software DEFORM-3D, simulation of forming process for closed type of cross wedge rolling was carried out. The distribution of the stress field and strain field during stretching stage is characterized as the metallic flowing of the rolling forming process. These results have great theoretical significance and engineering application value in the study of the generated mechanism of the end concavity for the closed type of cross wedge rolling and the improvement of the quality of rolled piece end.

Influence Rules of Technological Parameters on End Quality in Closed Cross Wedge Rolling (CWR)

In order to raise the efficience of materials' utilization and realize the CWR without the stub bar, this paper will focus on the closed CWR forming shafts,applying finite element software DEFORM-3D to do numerical simulation calculation for the process and studying the end quality of shafts.This paper has obtained the influence rule of the forming angle α, broadening angle β, reduction of area ψ and billet diameter D four process parameters on the end quality of the closed type CWR .The research results has showed that the length of concavity goes up along with the forming angle decrease;the same as the broadening angle; while the length of concavity goes up along with the billet diameter increase.and the reduction of area ψ has made a vital influence on the end quality of shafts,this conclusion has made a solid theoretical foundation and referential value for closed CWR .

MATHEMATICAL MODELING OF THE STRESS-STRAIN STATE OF THE METAL ROLLING IN BAR CALIBERS

With the use of specialized software DEFORM 3D the stress-strain state of the metal rolling in a simple form of high-quality caliber has been investigated. As applied to rolling conditions in box, rhombus and oval calibers it has been found interconnection between the stress-strain state of the metal in the volume of the deformed workpiece and the passage of the surface layers of the metal. With the use of the data a new calibration of light-section mill rolls 250-2 of JCS “Evraz ZSMK” has been developed, the implementation of which has improved the quality of the surface of the rolled section.