Method for Calculating of Cross-Sectional Dimensions of Sheet Blank at Intermediate Stages of Roller Forming Process

2018 ◽  
Author(s):  
Sergey Povorov ◽  
Ivan Semenov
Keyword(s):  
Forming Process ◽  
Cross Sectional ◽  
Sheet Blank

Identification of the Location of Conductive Filaments Formed in Pt/NiO/Pt Resistive Switching Cells and Investigation on Their Properties

2012 ◽  
Vol 1430 ◽  
Author(s):  
Tatsuya Iwata ◽  
Yusuke Nishi ◽  
Tsunenobu Kimoto
Keyword(s):  
Resistive Switching ◽  
Chemical Properties ◽  
Cell Resistance ◽  
Forming Process ◽  
Tem Analysis ◽  
Cross Sectional ◽  
Size And Shape

ABSTRACTExact locations of conductive filaments formed in NiO-based resistive switching (RS) cells were detected by C-AFM, and their electrical as well as chemical properties were investigated. After a forming process, a part of top electrodes of Pt/NiO/Pt RS cells is deformed. NiO layers are also deformed, and conductive spots, i.e. filaments have been found preferentially along the edges of deformations. Detailed C-AFM investigation has revealed that variation of cell resistances originates from differences in size and shape of filaments, not their resistivity. Furthermore, cross-sectional TEM analysis has demonstrated that filaments determining cell resistance consist of reduced NiO with an inclusion of Pt.

Hot Spline Forming of Ultra-High Strength Steel Gear Drum Using Resistance Heating

2014 ◽  
Vol 622-623 ◽  
pp. 201-206 ◽  
Author(s):  
Kenichiro Mori ◽  
Tomoyoshi Maeno ◽  
Shohei Nakamoto
Keyword(s):  
Deep Drawing ◽  
High Strength Steel ◽  
Side Wall ◽  
High Strength ◽  
Axial Direction ◽  
Resistance Heating ◽  
Sectional Area ◽  
Forming Process ◽  
Cross Sectional ◽  
Ultra High Strength Steel

A hot spline forming process of die-quenched gear drums using resistance heating of a side wall of a cup formed by cold deep drawing and ironing was developed. The side wall having uniform cross-sectional area is resistance-heated by passage of the current in the axial direction, the heated side wall of the drawn cup is ironed and is finally die-quenched. The gear drum was successfully formed and the hardness was between 400 and 500 HV. Not only the formability was improved but also the formed dram was hardly oxidised because of rapid resistance heating.

Springback Evaluation of 304 Stainless Steel in an Electrically Assisted Air Bending Operation

2016 ◽  
Author(s):  
Abdelrahim Khal ◽  
Brandt J. Ruszkiewicz ◽  
Laine Mears
Keyword(s):  
Electric Current ◽  
General Term ◽  
Bending Test ◽  
304 Stainless Steel ◽  
Forming Process ◽  
Cross Sectional ◽  
Air Bending ◽  
Research Fields ◽  
Electrically Assisted ◽  
Microstructural Evaluation

Driven by the automotive industry’s drive towards lightweighting, electrically assisted forming (EAF) is one of the most rapidly growing research fields in bulk deformation, and is classified under the general term “Electrically-Assisted Manufacturing (EAM)”. In EAF electric current (continuous or intermittent) is applied to a metallic sheet during the forming process, leading to numerous advantageous effects that have been studied and proven by several research groups and for different structural metals, such as reduced forming load and flow stress, increased formability, and reduction (or even elimination) of springback. Electrically-assisted bending (EAB) is a recent evolution of EAF technique, with the aim of capitalizing on the aforementioned advantages of EAF technique. In this work the effects of the EAB process on the final springback in an air bending test are identified, with the metal sheet being bent under different electrical field conditions. In addition, a comparison between the effects of applying the current during forming versus post forming are investigated. It was found that in general, higher current density (amount of current through cross sectional area of specimen (A/mm2), more frequent pulse period, and longer pulse duration all resulted in a greater degree of springback reduction. A microstructural evaluation showed no change in grain size in the presence of electric current.

Optimizing Roll Forming Processes with the Aid of a New Numerical Algorithm

2012 ◽  
Vol 504-506 ◽  
pp. 857-862 ◽  
Author(s):  
Ahmad Abrass ◽  
Thomas Kessler ◽  
Peter Groche
Keyword(s):  
Numerical Algorithm ◽  
Numerical Algorithms ◽  
Roll Forming ◽  
Design Parameters ◽  
Fe Model ◽  
Forming Process ◽  
Cross Sectional ◽  
Cross Sectional Profile ◽  
Sectional Profile ◽  
Roll Forming Process

For the manufacturing of large quantities of profile-shaped products, the roll forming process represents one of the most effective metal forming technologies. During this process, the sheet metal will be formed into a desired cross-sectional profile using successive pairs of forming rolls. This process is well known as a very complex process in industry because of the multiplicity of the process and design parameters. For that reason, the optimization of roll forming processes using numerical methods like the finite element method is very complex and time-consuming. In this paper, a numerical method will be introduced to accelerate the simulation and to optimize the roll forming process. The newly developed algorithm will be illustrated and validated by analyzing the roll forming process. The details of the FE-model and the numerical algorithm will be described. Furthermore, the results of the numerical simulation with and without the application of the numerical algorithms will be compared. Finally, the process will be optimized using the newly developed method.

Strain Rules of Cross Wedge Rolling Asymmetric Shaft-Parts Based on the Parity Wedge

2012 ◽  
Vol 201-202 ◽  
pp. 1066-1070
Author(s):  
Zhan Li ◽  
Xue Dao Shu ◽  
Wen Fei Peng ◽  
Bao Shou Sun
Keyword(s):  
Theoretical Foundation ◽  
Longitudinal Section ◽  
Rolling Process ◽  
Field Analysis ◽  
Key Factors ◽  
Cross Wedge Rolling ◽  
Forming Process ◽  
Cross Sectional ◽  
Strain Fields ◽  
Forming Mechanism

The analysising of strain is the key factors to understand the forming mechanism of cross wedge rolling asymmetric shaft. due to the extrusion of dies and other external force, its interior,interactions can cause the relative position between the various parts. In order to study the deformation of workpiece at different degrees, pulling in the finite element strain field analysis, the strain of the analysis at deformation process is also a necessary precondition for forming and stress distribution. In this papre,By using Deform3D platform, the forming process of the cross wedge rolling on parity wedge asymmetric shaft is simulated. It is also to be analyzed the distribution and variation of the amount of strain in the rolling process, it shows that a cross-sectional and longitudinal section about the deformation characteristics of the strain fields, the results can achieve production of cross wedge rolling and provide important theoretical foundation to promote further cross-wedge rolling.

Cure kinetics of PF/PVAc hybrid adhesive for manufacturing profiled wood-strand composites

Holzforschung ◽  
2010 ◽  
Vol 64 (5) ◽  
Author(s):  
Yi Wang ◽  
Vikram Yadama ◽  
Marie-Pierre Laborie ◽  
Debes Bhattacharyya
Keyword(s):  
Hot Pressing ◽  
Phenol Formaldehyde ◽  
Cure Kinetics ◽  
Roll Forming ◽  
Good Prediction ◽  
Forming Process ◽  
Scanning Calorimetry ◽  
Cross Sectional ◽  
Kinetics Of ◽  
Wood Strand

Abstract In thermoforming of profiled wood-strand composites, an adhesive system is needed to provide a weak initial bond to maintain mat integrity and architecture during the forming process and eventually a durable bond when the final cross-sectional shape is achieved. A hybrid adhesive composed of phenol formaldehyde (PF) and poly(vinyl acetate) (PVAc) is proposed in this study. The cure kinetics of this hybrid adhesive and bond development in a multi-step hot-pressing is discussed. Cure kinetics studied by differential scanning calorimetry indicated that adding PVAc slowed down the curing reaction of PF resin; however, the full cure of PF was not inhibited. The nth-order Borchardt Daniels (nth-BD) model provided good prediction for the curing of adhesives with a PF/PVAc ratio lower than 1:1. To simulate roll forming of wood-strand mats, a hot-pressing schedule at low temperature combined with multi-stage closing and opening was developed. The nth-BD model was able to predict the actual bond development for composites made with neat PF resin. The results indicated that cure kinetics of a PF/PVAc hybrid adhesive would not significantly differ from neat PF resin for blend ratios of 1:1 or lower, thus potentially providing a resin system for roll forming or matched-die forming of wood-strand composites.

Effect of Friction Stir Forming Process Parameters on Mechanical Interlock between A5083Alloy and Ultra-Thin Stainless Steel Strands

2020 ◽  
Vol 858 ◽  
pp. 27-32
Author(s):  
Hamed Mofidi Tabatabaei ◽  
Keita Kobayashi ◽  
Takahiro Ohashi ◽  
Tadashi Nishihara
Keyword(s):  
Stainless Steel ◽  
Aluminium Alloy ◽  
Alloy Composite ◽  
Forming Process ◽  
Cross Sectional ◽  
Bending Tests ◽  
Friction Stir ◽  
Specific Strength ◽  
Eds Analysis ◽  
Grain Distribution

Fibre-reinforced materials have gathered attention because of their significant properties such as heat resistance, abrasion resistance and specific strength. The present study proposes a new method of joining stainless steel strands with an aluminium alloy using friction stir forming and analyses the formation of a fibre-reinforced aluminium alloy composite material. Mechanical interlocks between the strands and the aluminium alloy are evaluated based on cross-sectional microstructure observations and EDS analysis. The tensile test indicated an increasing tendency of strength by increasing the number of strands and bending tests showed that higher strength is achieved in rare bend because of inhomogeneous grain distribution after friction stir forming (FSF).

Forming Process of Wire and Arc Additive Manufacture

2021 ◽  
Vol 1035 ◽  
pp. 198-205
Author(s):  
Lei Zou ◽  
Lei Li ◽  
Jian Hua Cai ◽  
Hai Ying Yang ◽  
Jun Chen
Keyword(s):  
Cross Sections ◽  
Single Layer ◽  
Weld Bead ◽  
Additive Manufacture ◽  
Feed Speed ◽  
Forming Process ◽  
Cross Sectional ◽  
Weld Current ◽  
Wire Feed Speed ◽  
The Cross

The forming process of wire and arc additively manufacture (WAAM) was studied using the self-developed and designed WAAM system. The single-pass and single-layer weld bead samples were prepared with different process parameters, and the cross-sectional dimensions of the weld bead were measured. The influence rules of weld current, welding speed, wire feed speed and welding height on the weld bead size were obtained. In addition, the overlap experiment of the WAAM forming process was also carried out. The multiple and multilayer lap samples with different overlap rates were prepared, and the cross-sections of the lap samples were observed and analyzed. Finally, the overlap rate range of 35-45% with good forming effect was obtained.

scholarly journals Spatial Distribution Evolution of Residual Stress and Microstructure in Laser-Peen-Formed Plates

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3612
Author(s):  
Zheng Zhang ◽  
Wen Huang ◽  
Guoxin Lu ◽  
Yongkang Zhang
Keyword(s):  
Residual Stress ◽  
Compressive Stress ◽  
Compensation Effect ◽  
Large Deflection ◽  
X Ray Diffraction ◽  
Forming Process ◽  
Cross Sectional ◽  
Near Surface ◽  
Low Stiffness ◽  
Deformation Compatibility

Residual stress in structural components is crucial as it affects both service performance and safety. To investigate the evolution of residual stress in a laser-peen-formed panel, this study adopted two plate samples of thickness 3 and 9 mm instead of the conventional Almen strip. The two plates were peened with an identical energy density of 10.99 GW/cm2. The residual stress across the entire section was determined using a slitting method, and near-surface stress was then verified by X-ray diffraction. Furthermore, cross-sectional variation in hardness and microstructure were characterized to understand the residual stress evolution. The experimental results showed that different thicknesses resulted in distinct spatial distributions of residual stress. The 3-mm plate demonstrated a shallow (0.5 mm) and lower compressive stress magnitude (−270 MPa) compared with a deeper (1 mm) and higher compressive stress (−490 MPa) in the 9-mm plate. Further analysis revealed that the deformation compatibility during the forming process inevitably leads to a stress compensation effect on the peened side. The decrease in the depth and magnitude of the compressive residual stress in the thin plate was mainly attributed to low stiffness and large deflection.

Sign in / Sign up

Export Citation Format

Share Document