Numerical Study of the Flow Forming Process of AISI 630 Stainless Steel

Flow forming is one of the cold forming process which is used for hollow symmetrical shapes. In this paper, the forward flow forming process is simulated using the finite element method and its results are compared with the experimental process. The variation of thickness of the sample is examined by the ultrasonic tests for the five locations of the tubes. To simulate the process, the ABAQUS explicit is used. The effects of flow forming variables such as the angle of rollers and rate of feeding of rollers, on the external variables such as internal diameter, thickness of tube and roller forces are considered. The study showed that the roller force and surface defects were reduced with low feeding rate and low rollers attack angles. Moreover, the sample internal diameter increased at low feeding rate and low rollers attack angles. The optimum variables for flow forming process were also obtained.

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Development of ANFIS Model for Flow Forming of Solution Annealed H30 Aluminium Tubes

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.261.378 ◽

2017 ◽

Vol 261 ◽

pp. 378-385

Author(s):

Bikramjit Podder ◽

Prabas Banerjee ◽

K. Ramesh Kumar ◽

Nirmal Baran Hui

Keyword(s):

Fuzzy Inference ◽

Speed Ratio ◽

Internal Diameter ◽

Feed Speed ◽

Forming Process ◽

Flow Forming ◽

Inference System ◽

Cold Flow ◽

Additional Process ◽

Very High

Modeling of the cold flow forming process for manufacturing of tube shaped solution annealed H30 Aluminum alloy has been considered in this present study. Three inputs (feed-speed ratio, roller in-feed and roller axial stagger) and three outputs viz. spring back, ovality and internal diameter have been considered for the present study.. Adaptive network-based fuzzy inference system (ANFIS) in Matlab platform has used for modeling purposes and its performance is compared with regression model. ANFIS has completely outperformed the regression models. Percentage accuracy in predicting all the three responses are found to be very high with ANFIS models. Prediction of ovality against the test data using regression analysis is found to be extremely erroneous. It indicates that additional process parameters are involved in predicting ovality which are not captured during the experimentation.

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Diametral Growth and Hardness Variation in Al6101 T6 during Flow Forming

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.b7833.129219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 4370-4374

Keyword(s):

Experimental Data ◽

Linear Relation ◽

Mechanical Response ◽

Aerospace Industry ◽

Thickness Reduction ◽

Internal Diameter ◽

Forming Process ◽

Flow Forming ◽

Hardness Variation ◽

Increase With Increase

Flow forming is an emerging process being widely used for manufacturing axisymmetric components that are used in the aerospace industry and automobile industries. In the present investigation, the mechanical response of the Al6101 T6 workpiece to the flow forming process has been studied. The study showed that the microhardness of the preform increased by 20.2% higher at 60% thickness reduction as compared to hardness value at 10% thickness reduction. A linear relation between the hardness variation and thickness reduction has been proposed based on experimental data. The internal diameter was found to increase with increase in the thickness reduction. In the present investigation, a 3mm increase in diameter was seen in the 120mm length.

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Experimental and Numerical Study of Cold Helical Rolling of Small-Diameter Steel Balls

10.21203/rs.3.rs-447338/v1 ◽

2021 ◽

Author(s):

Shengqiang Liu ◽

Jinping Liu ◽

Hao Xu ◽

Zhipeng Wang ◽

Jinxia Shen ◽

...

Keyword(s):

Work Hardening ◽

Fe Simulation ◽

Numerical Study ◽

Rolling Force ◽

Effective Strain ◽

Small Diameter ◽

Helical Rolling ◽

Forming Process ◽

Cold Forming ◽

Steel Balls

Abstract Cold helical rolling (CHR) is one of the most effective ways to produce small-diameter steel balls. In this study, one kind of work hardening model was established and implemented into Simufact 15.0 to investigate the work hardening phenomenon in the cold forming process. Firstly, based on the helical rolling theory, a set of finite element (FE) simulations was developed. The influence of CHR parameters, including the starting height of convex rib, forming area length, and rolling inclination angle, on the forming process was studied via simulation. Furtherly, the CHR process experiments and FE simulation were carried out , the results showed that the FE simulation was in good agreement with the experimental results, and consistent with the predicted value of the theoretical calculation. Finally, the evolution of effective strain, effective stress, rolling force, work hardening and microstructure during the cold helical rolling of Φ 5.12 mm steel balls was investigated via FE. As result, the evolution trend of hardness was consistent with that of dislocation density, indicating that the model is credible. Besides, the microstructure of the steel ball at different positions further verified this.

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Three Dimensional Finite Element Analysis of Staggered Backward Flow Forming Process

Volume 1: Processing ◽

10.1115/msec2013-1219 ◽

2013 ◽

Author(s):

Hemant Shinde ◽

Pushkar Mahajan ◽

Ramesh Singh ◽

K. Narasimhan

Keyword(s):

Finite Element ◽

Three Dimensional ◽

Process Conditions ◽

State Variables ◽

Forming Process ◽

Flow Forming ◽

Element Analysis ◽

Cold Forming ◽

Cylindrical Workpiece ◽

Backward Flow Forming

Flow forming is one of the cold forming processes which is mainly used to produce thin-walled high-precision tubular components. A three dimensional coupled-field thermo-mechanical finite element model for staggered three-roller backward flow forming of a cylindrical workpiece of MDN-250 maraging steel has been developed using Abaqus/Explicit. In this model, the effect of tip radius of the rollers and friction between the rollers and the workpiece has been considered. The bottom of the workpiece is fixed in the axial direction so that diametral reduction and the axial elongation can be studied. Simulations have been carried out at different process conditions to study the state variables, such as stresses and strains obtained during the deformation. The model has been benchmarked with the experimental results for thickness reduction and the error in the thickness prediction is limited to 4%. The roll forces have been benchmarked against analytical formulation and a difference of 13–20% has been observed. The effect of flow forming process variables, such as feed rate and reduction ratio on the stress/strain distribution and roll forces have been studied. The results show that the roll forces increase at higher feed rates and higher reduction ratios whereas the equivalent strains increase at lower feed rates and higher reduction ratios. In addition, a parametric study has been conducted to study ovality, diametral growth, roll forces, stresses and strains as a function of process parameters.

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Challenges in the Forging of Steel-Aluminum Bearing Bushings

Materials ◽

10.3390/ma14040803 ◽

2021 ◽

Vol 14 (4) ◽

pp. 803

Author(s):

Bernd-Arno Behrens ◽

Johanna Uhe ◽

Tom Petersen ◽

Christian Klose ◽

Susanne E. Thürer ◽

...

Keyword(s):

Intermetallic Layer ◽

Dissimilar Materials ◽

Intermetallic Phases ◽

Internal Diameter ◽

External Diameter ◽

Forming Process ◽

High Deformation ◽

Eds Analysis ◽

Steel Aisi ◽

Metallurgical Bond

The current study introduces a method for manufacturing steel–aluminum bearing bushings by compound forging. To study the process, cylindrical bimetal workpieces consisting of steel AISI 4820 (1.7147, 20MnCr5) in the internal diameter and aluminum 6082 (3.2315, AlSi1MgMn) in the external diameter were used. The forming of compounds consisting of dissimilar materials is challenging due to their different thermophysical and mechanical properties. The specific heating concept discussed in this article was developed in order to achieve sufficient formability for both materials simultaneously. By means of tailored heating, the bimetal workpieces were successfully formed to a bearing bushing geometry using two different strategies with different heating durations. A metallurgical bond without any forging defects, e.g., gaps and cracks, was observed in areas of high deformation. The steel–aluminum interface was subsequently examined by optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). It was found that the examined forming process, which utilized steel–aluminum workpieces having no metallurgical bond prior to forming, led to the formation of insular intermetallic phases along the joining zone with a maximum thickness of approximately 5–7 µm. The results of the EDS analysis indicated a prevailing FexAly phase in the resulting intermetallic layer.

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DESIGN AND ANALYSIS OF NEW STENT PATTERNS FOR ENHANCED PERFORMANCE

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519420500396 ◽

2020 ◽

Vol 20 (06) ◽

pp. 2050039

Author(s):

NISANTHKUMAR PANNEERSELVAM ◽

SREEKUMAR MUTHUSWAMY

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Blood Flow ◽

Coronary Artery ◽

Mechanical Behavior ◽

Internal Diameter ◽

Cell Design ◽

The Finite Element Method ◽

Stent Expansion ◽

Stenting Procedure

Deploying a stent to restore blood flow in the coronary artery is very complicated, as its internal diameter is smaller than 3[Formula: see text]mm. It has already been proven that mechanical stresses induced on stent and artery during deployment make the placement of stent very difficult, besides the development of complications due to artery damage. Various stent designs have already been developed, especially in the metallic category. Still, there are possibilities for developing new stent designs and patterns to overcome the complexities of the existing models. Also, the technology of metallic stents can be carried forward towards the development of bioresorbable polymeric stents. In this work, three new stent cell designs (curvature, diamond, and oval) have been proposed to obtain better performance and life. The finite element method is utilized to explore the mechanical behavior of stent expansion and determine the biomechanical stresses imposed on the stent and artery during the stenting procedure. The results obtained have been compared with the available literature and found that the curvature cell design develops lower stresses and, hence, be suitable for better performance and life.

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Grain Size Modification by Micro Rotary Swaging

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.651-653.627 ◽

2015 ◽

Vol 651-653 ◽

pp. 627-632 ◽

Cited By ~ 7

Author(s):

Svetlana Ishkina ◽

Bernd Kuhfuss ◽

Christian Schenck

Keyword(s):

Grain Size ◽

Longitudinal Section ◽

Forming Process ◽

Boundary Area ◽

Cold Forming ◽

Flat Surfaces ◽

Rotary Swaging ◽

2D Simulation ◽

Physical Tests ◽

Formed Part

Rotary swaging is a well established cold forming process e.g. in the automotive industry. In order to modify the material properties by swaging systematically, a new process of swaging with asymmetrical strokes of the forming dies is investigated. The newly developed tools feature flat surfaces and do not represent the geometry of the formed part as in conventional swaging. Numerical simulation and physical tests are carried out with special regard to the resulting geometry, mechanical properties and the microstructure. During these tests copper wires with diameter d0=1 mm are formed. Regarding the microstructure in the longitudinal section of formed specimens, elongation of grains in the central part and grain size reduction in the boundary area are observed. Furthermore, this approach opens up new possibilities to configure the geometry of wires. 2D-simulation is applied and discussed in the paper to investigate change of the processed geometry (cross-section) and shear strain distribution during the rotary swaging process.

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Machine Learning Acoustic Emission Based Monitoring of Cold Forging for Smart Manufacturing: A Review

10.51626/ijeti.2021.02.00017 ◽

2021 ◽

Vol 2 (3) ◽

Keyword(s):

Machine Learning ◽

Acoustic Emission ◽

Product Quality ◽

High Speed ◽

High Rate ◽

Cold Forging ◽

Smart Manufacturing ◽

Forming Process ◽

Cold Forming ◽

Effective Manner

Cold forging is a high-speed forming technique used to shape metals at near room temperature. and it allows high-rate production of high strength metal-based products in a consistent and cost-effective manner. However, cold forming processes are characterized by complex material deformation dynamics which makes product quality control difficult to achieve. There is no well defined mathematical model that governs the interactions between a cold forming process, material properties, and final product quality. The goal of this work is to provide a review for the state of research in the field of using acoustic emission (AE) technology in monitoring cold forging process. The integration of AE with machine learning (ML) algorithms to monitor the quality is also reviewed and discussed. It is realized that this promising technology didn’t receive the deserving attention for its implementation in cold forging and that more work is needed.

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