Application of nonlocal friction in several kinds of plastic forming problems

2005 ◽  
Vol 26 (11) ◽  
pp. 1420-1426
Author(s):  
Xiao-qing Yan ◽  
Hai-bao Luo ◽  
Ming-fu Fu ◽  
Wu-gui Jiang
Keyword(s):  
Nonlocal Friction ◽  
Plastic Forming

INCONEL ALLOY 718SPF

Alloy Digest ◽  
1994 ◽  
Vol 43 (11) ◽  
Keyword(s):  
Base Alloy ◽  
Low Flow ◽  
Inconel Alloy ◽  
Gamma Prime ◽  
Size Stability ◽  
Super Plastic ◽  
Plastic Forming ◽  
Super Plastic Forming ◽  
Grain Size Stability ◽  
Prime Phase

Abstract INCONEL alloy 718SPF is an age-hardenable austenitic material whose strength is largely dependent on the precipitation of a gamma prime phase following heat treatment. The base alloy, however, possesses two-essential characteristics for super-plastic forming; grain size stability over time and temperature; and a combination of low flow stress and significant ductility. This datasheet provides information on composition, physical properties, microstructure, hardness, elasticity, and tensile properties as well as creep and fatigue. It also includes information on low and high temperature performance. Filing Code: Ni-471. Producer or source: Inco Alloys International Inc.

A Study on the Flow Behavior of 42CrMo Steel under Hot Compression by Thermal Physical Simulations

2010 ◽  
Vol 108-111 ◽  
pp. 494-499
Author(s):  
Ying Tong ◽  
Guo Zheng Quan ◽  
Gang Luo ◽  
Jie Zhou
Keyword(s):  
Strain Rate ◽  
Flow Behavior ◽  
Rate Sensitivity ◽  
Strain Hardening Exponent ◽  
Forming Process ◽  
Material Parameters ◽  
Basic Model ◽  
42Crmo Steel ◽  
Plastic Forming ◽  
Physical Simulations

This work was focused on the compressive deformation behavior of 42CrMo steel at temperatures from 1123K to 1348K and strain rates from 0.01s-1 to 10s-1 on a Gleeble-1500 thermo-simulation machine. The true stress-strain curves tested exhibit peak stresses at small strains, after them the flow stresses decrease monotonically until high strains, showing a dynamic flow softening. And the stress level decreases with increasing deformation temperature and decreasing strain rate. The values of strain hardening exponent n, and the strain rate sensitivity exponent m were calculated the method of multiple linear regression, the results show that the two material parameters are not constants, but changes with temperature and strain rate. Then the two variable material parameters were introduced into Fields-Backofen equation amended. Thus the constitutive mechanical discription of 42CrMo steel which can accurately describe the relationships among flow stress, temperature, strain rate, strain offers the basic model for plastic forming process simulation.

scholarly journals Plastic forming processes of transverse non-homogeneous composite metallic sheets

2021 ◽  
Vol 11 (1) ◽  
pp. 294-302
Author(s):  
Gal Davidi
Keyword(s):  
Inner Core ◽  
Plastic Material ◽  
Radial Solution ◽  
Algebraic Differential Equation ◽  
Forming Process ◽  
Perfectly Plastic ◽  
Plastic Forming ◽  
Validity Limit ◽  
Significant Achievement

Abstract In this work an analysis of the radial stress and velocity fields is performed according to the J 2 flow theory for a rigid/perfectly plastic material. The flow field is used to simulate the forming processes of sheets. The significant achievement of this paper is the generalization of the work by Nadai & Hill for homogenous material in the sense of its yield stress, to a material with general transverse non-homogeneity. In Addition, a special un-coupled form of the system of equations is obtained where the task of solving it reduces to the solution of a single non-linear algebraic differential equation for the shear stress. A semi-analytical solution is attained solving numerically this equation and the rest of the stresses term together with the velocity field is calculated analytically. As a case study a tri-layered symmetrical sheet is chosen for two configurations: soft inner core and hard coating, hard inner core and soft coating. The main practical outcome of this work is the derivation of the validity limit for radial solution by mapping the “state space” that encompasses all possible configurations of the forming process. This configuration mapping defines the “safe” range of configurations parameters in which flawless processes can be achieved. Several aspects are researched: the ratio of material's properties of two adjacent layers, the location of layers interface and friction coefficient with the walls of the dies.

scholarly journals Introduction to the Mechanics of Plastic Forming of Metals

1980 ◽  
Vol 47 (2) ◽  
pp. 459-460
Author(s):  
W. Szczepinski ◽  
S. Kobayashi
Keyword(s):  
Plastic Forming

Coupled Thermo-Mechanical FEA of Three-Roll Cross Rolling Process for Rings with Small-Hole and Deep Groove

2012 ◽  
Vol 560-561 ◽  
pp. 846-852 ◽  
Author(s):  
Qi Ma ◽  
Lin Hua ◽  
Dong Sheng Qian
Keyword(s):  
Rolling Process ◽  
Small Hole ◽  
Fe Model ◽  
Forming Process ◽  
Software Environment ◽  
Cross Rolling ◽  
Design And Optimization ◽  
Forming Technology ◽  
Deep Groove ◽  
Plastic Forming

Ring parts with small-hole and deep groove such as duplicate gear and double-side flange, are widely used in various engineering machineries. Three-roll cross rolling (TRCR) is a new advanced plastic forming technology for the processing of rings with small-hole and deep groove. In this paper, a 3D coupled thermo-mechanical FE model for TRCR of ring with small-hole and deep groove is established under ABAQUS software environment. By simulation and analysis, the evolution and distribution laws of strain and temperature in the forming process are revealed, and the effects of the key process parameters on the deformation uniformity are explored. The results provide valuable guideline for the technological parameter design and optimization.

Plastic Forming Processes Through Rotating Conical Dies1

2001 ◽  
Vol 68 (6) ◽  
pp. 894-902 ◽  
Author(s):  
D. Durban ◽  
G. Davidi ◽  
D. Lior
Keyword(s):  
Single Phase ◽  
Large Strain ◽  
Single Layer ◽  
Wall Friction ◽  
Nonlinear Ordinary Differential Equations ◽  
Tube Forming ◽  
Perfectly Plastic ◽  
Governing System ◽  
Plastic Forming ◽  
Exact Relations

Drawing and extrusion of single-phase and multilayered tubes through rotating conical dies is investigated within the framework of continuum plasticity. Large strain perfectly plastic J2 flow theory models constitutive behavior along with a radial-helical flow pattern. The governing system for a single-layer process is reduced to three coupled nonlinear ordinary differential equations. An approximate solution is developed for long and tapered working zones with low wall friction. That solution is used to simulate the field within each layer in composite tube forming. Exact relations are derived for the n-layered tube and it is shown that wall rotation can considerably reduce the required working loads. Dedicated to Professor Dietmar Gross on the occasion of his 60th birthday

scholarly journals Simulation of plastic forming process of shells with minimal thickness fluctuations

2017 ◽  
Vol 201 ◽  
pp. 489-494
Author(s):  
E.G. Demyanenko ◽  
I.P. Popov ◽  
A.N. Epifanov
Keyword(s):  
Forming Process ◽  
Minimal Thickness ◽  
Plastic Forming

Drawing of Square Blanks in a Cylindrical Die with Controlled Movement of the Edges

2021 ◽  
Vol 1037 ◽  
pp. 281-286
Author(s):  
Sergey Nikolaevich Larin ◽  
Nikita A. Samsonov
Keyword(s):  
Computer Modeling ◽  
Experimental Work ◽  
Metal Loss ◽  
Additional Increase ◽  
Plastic Forming ◽  
Reduce Metal Loss ◽  
Main Operation

Plastic forming, in many cases, includes the drawing of hollow cylindrical products as the main operation. For the manufacture of such products, round blanks are used as semi-finished products. However, during the blank production from strips or tapes, their geometry causes a very significant metal loss. A very effective way to reduce metal loss is to replace round billets with square ones. The use of square blanks gives an additional increase in the height of the products. In this regard, the article investigates the drawing of a square blank into a cylindrical die. The research was carried out on the basis of the analysis of experimental work and computer modeling. According to the results of the research the rational ratios of the geometric dimensions of the tool and workpieces are found.

Elastic-Plastic FEM Analysis of Deformations of a Cylinder Subjected to Severe Uniaxial and Bilateral Compression by Flat Plates

1991 ◽  
Author(s):  
M. Gotoh ◽  
Y. Shibata
Keyword(s):  
Compressive Force ◽  
Fem Analysis ◽  
Plane Stress State ◽  
Deformation Pattern ◽  
Lateral Compression ◽  
The Finite Element Method ◽  
Ring Plane ◽  
Flat Plates ◽  
Elastic Plastic ◽  
Plastic Forming

Abstract Uni-lateral and bi-lateral elastic-plastic compressions of a circular cylinder with three different wall thicknesses by flat plates are numerically analysed by the Finite Element Method (FEM). J2-flow theory (J2F), and J2-Gotoh’s corner theory (J2G) which was previously proposed by one of the authors are used as the constitutive equations. In the case of uni-lateral compression, the cylinder is compressed up to a completely flattened shape, which is considered a kind of plastic forming processes. The deformed shapes and the compressive force are predicted better by J2G than by J2F. The spring-back behaviours are also analysed by imposing unloading process during deformation. The deformation process in the compression of a ring (plane stress state) and a spherical shell (axi-symmetric state) is also analysed. In the case of bi-lateral compression, the process is considered a kind of square-tube forming. In its final stage, the cylinder deforms into a completely unexpected shape which could be thought of as a square tube reinforced with ribs. The J2G allows the process to proceed at a lower compressive force than that for J2F. The effect of n-value (the strain-hardedning exponent) on the deformation pattern is also discussed.

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