Friction Force and Stresses Analysis for Contact of Assembled Details

2006 ◽  
Vol 113 ◽  
pp. 334-338
Author(s):  
Z. Dreija ◽  
O. Liniņš ◽  
Fr. Sudnieks ◽  
N. Mozga
Keyword(s):  
Mechanical Properties ◽  
Surface Roughness ◽  
Plastic Deformation ◽  
Friction Force ◽  
Sliding Friction ◽  
Friction Model ◽  
Contact Interface ◽  
Finite Element Program ◽  
Elastic Plastic ◽  
Element Program

The present work deals with the computation of surface stresses and deformation in the presence of friction. The evaluation of the elastic-plastic contact is analyzed revealing three distinct stages that range from fully elastic through elastic-plastic to fully plastic contact interface. Several factors of sliding friction model are discussed: surface roughness, mechanical properties and contact load and areas that have strong effect on the friction force. The critical interference that marks the transition from elastic to elastic- plastic and plastic deformation is found out and its connection with plasticity index. A finite element program for determination contact analysis of the assembled details and due to details of deformation that arose a normal and tangencial stress is used.

scholarly journals Calculation and AFM Experimental Research on Slip Friction for Unlubricated Spherical Contact with Roughness Effect

Micromachines ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1428
Author(s):  
Shengguang Zhu ◽  
Liyong Ni
Keyword(s):  
Friction Force ◽  
Sliding Friction ◽  
Static Friction ◽  
Friction Model ◽  
Rigid Sphere ◽  
Roughness Effect ◽  
Force Microscopy ◽  
Comparison Results ◽  
Experimental Values ◽  
Calculation Models

Previous research on friction calculation models has mainly focused on static friction, whereas sliding friction calculation models are rarely reported. In this paper, a novel sliding friction model for realizing a dry spherical flat contact with a roughness effect at the micro/nano scale is proposed. This model yields the sliding friction by the change in the periodic substrate potential, adopts the basic assumptions of the Greenwood–Williamson random contact model about asperities, and assumes that the contact area between a rigid sphere and a nominal rough flat satisfies the condition of interfacial friction. It subsequently employs a statistical method to determine the total sliding friction force, and finally, the feasibility of this model presented is verified by atomic force microscopy friction experiments. The comparison results show that the deviations of the sliding friction force and coefficient between the theoretical calculated values and the experimental values are in a relatively acceptable range for the samples with a small plasticity index (Ψ ≤ 1).

Energy-Dissipation Mechanisms and Seismic Design Recommendation of Eccentrically Braced Steel Frames

2011 ◽  
Vol 71-78 ◽  
pp. 3662-3665
Author(s):  
Bao Cheng Zhao ◽  
Qiang Gu
Keyword(s):  
Plastic Deformation ◽  
Energy Dissipation ◽  
Seismic Design ◽  
Steel Frames ◽  
Shell Element ◽  
Elastic Stiffness ◽  
Collapse Mechanism ◽  
Finite Element Program ◽  
Earthquake Load ◽  
Element Program

Eccentrically braced steel frames are a lateral load-resisting system which apply high intensity area and it can provide the high elastic stiffness that met higher steel building drift requirement. This paper first provides an introduction of Forces in links and Energy dissipation mechanisms of eccentrically braced steel frames. In that Eccentrically braced steel frames will collapse after the link beams go into plastic deformation under earthquake load, A new analytical model which include shell element apply to link beams with large deformation and plastic deformation and beams element apply to other parts of structure is presented in this paper for analyzing eccentrically braced steel frames energy-dissipation behavior and collapse mechanism. Computer program is complied. After this paper applies nonlinear finite element program to analyze the behaviors of eccentrically braced steel frames under cyclic load, the seismic design recommendations of eccentrically brace are presented.

Predicting the Impact of Quenching on Mechanical Properties of Complex-Shaped Aluminum Alloy Parts

1995 ◽  
Vol 117 (2) ◽  
pp. 479-488 ◽  
Author(s):  
D. D. Hall ◽  
I. Mudawar
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Aluminum Alloy ◽  
Boundary Conditions ◽  
Finite Element Program ◽  
Part Geometry ◽  
Heat Treated ◽  
Element Program ◽  
Nozzle Configuration ◽  
The Impact

The mechanical properties of age-hardenable aluminum alloy extrusions are critically dependent on the rate at which the part is cooled (quenched) after the forming operation. The present study continues the development of an intelligent spray quenching system, which selects the optimal nozzle configuration based on part geometry and composition such that the magnitude and uniformity of hardness (or yield strength) is maximized while residual stresses are minimized. The quenching of a complex-shaped part with multiple, overlapping sprays was successfully modeled using spray heat transfer correlations as boundary conditions within a finite element program. The hardness distribution of the heat-treated part was accurately predicted using the quench factor technique; that is, the metallurgical transformations that occur within the part were linked to the cooling history predicted by the finite element program. This study represents the first successful attempt at systematically predicting the mechanical properties of a quenched metallic part from knowledge of only the spray boundary conditions.

Seismic Elastic-Plastic Analysis on Outer-Jacketing Mega Frame for Story-Adding by IDARC-2D

2011 ◽  
Vol 255-260 ◽  
pp. 209-214
Author(s):  
Xu Jie Sun ◽  
Jian Ping Cao ◽  
Wen Zhong Zheng
Keyword(s):  
Prestressed Concrete ◽  
Seismic Behavior ◽  
Engineering Application ◽  
Test Results ◽  
Loading Test ◽  
Restoring Force ◽  
Finite Element Program ◽  
Static Test ◽  
Elastic Plastic ◽  
Element Program

To make sure the seismic behavior of outer-jacketing mega frame for storey-adding, a low-cyclic loading test of prestressed concrete beam and a pseudo-static test of Mega frame were analyzed by elastic-plastic finite element program IDARC2D, compared with the test results, skeleton hysteretic curves and restoring force models of structural member were determined. They were used in IDARC2D to study the seismic behavior of mega frame for storey-adding. Some structures designed complied with the Code for Seismic Design of Buildings (GB50011-2001) and correlative literatures about collapse, these structures were reanalyzed after enhancing their seismic measures suitably, collapse were avoided. They are: the main frame of outer-jacketing mega frame in the zone of seismic fortification intensity 8 conforming to seismic grade 1-st, the height of mega frame under 50m conforming to seismic grade 2-nd and that over 50m conforming to seismic grade 1-st in zone of seismic fortification intensity 7. Research achievements will provide reference to engineering application of this structural system.

scholarly journals Mechanical Properties Of The Ceramic Open-Cell Foams Of Variable Cell Sizes

2015 ◽  
Vol 60 (3) ◽  
pp. 1957-1964 ◽  
Author(s):  
Z. Nowak ◽  
M. Nowak ◽  
R.B. Pęcherski ◽  
M. Potoczek ◽  
R.E. Śliwa
Keyword(s):  
Mechanical Properties ◽  
Numerical Model ◽  
Compression Test ◽  
Young Modulus ◽  
Vertical Displacement ◽  
Finite Element Program ◽  
Open Cell ◽  
Open Cell Foam ◽  
Element Program ◽  
Deformation Processes

AbstractThe mechanical properties and numerical model of ceramic alumina open-cell foam, which is produced by the chemical method of gelcasting with different cell sizes (porosities) are presented. Geometric characteristics of real foam samples were estimated from tomographic and scanning electron microscopy images. Using this information, numerical foam model was proposed. A good agreement between the numerical model and the results elaborated from microtomography was obtained. To simulate the deformation processes the finite element program ABAQUS was used. The main goal of this computation was to obtain macroscopic force as a function of applied vertical displacement in compression test.As a result of numerical simulation of compression test of alumina foam for different values of porosity, the Young modulus and the strength of such foams were estimated.

scholarly journals The force required for the creation of wood cuttings

2021 ◽  
Vol 1208 (1) ◽  
pp. 012024
Author(s):  
Hasan Talić
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Cutting Force ◽  
Friction Force ◽  
Rear Surface ◽  
Cutting Speed ◽  
Wood Moisture ◽  
Cutting Power ◽  
Number Of Factors ◽  
The Creation

Abstract Wood as a material has its own peculiar role during processing due to its characteristics which depend on a number of factors. Therefore, wood-based plate materials tend to encounter the same issues. The creation of the continuous cuttings is conditioned by the strength as it is being cut orthogonally. The cutting force is shown as the sum of the forces for plastic deformation, the force for overcoming the work of the friction force on the front and rear surface of the tool and the force for creating a new surface. Each of the forces is connected to appropriate mechanical features of wood. Examining the mechanical properties of wood, which can be used to calculate the required power to create a new surface, demonstrates the dependence of cutting power on the type of wood, cutting speed, and wood moisture.

Properties of Al-Si-Fe-Cu-Mg Alloy PM Composites Obtained by Closed - Die Forging and Heat Treatment

2010 ◽  
Vol 638-642 ◽  
pp. 1842-1847
Author(s):  
Stefan Szczepanik ◽  
Marek Wojtaszek
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Cross Section ◽  
Bend Strength ◽  
Powder Mixtures ◽  
Finite Element Program ◽  
Die Forging ◽  
Closed Die Forging ◽  
Element Program ◽  
Simulated Distribution

Aluminium RAl-1 and its alloy Al17Si5Fe3Cu1.1Mg0.6Zr composite materials were manufactured from powder mixtures by cold pressing, hot closed-die forging at 480oC and heat treatment. Powders ranging in composition in 20 wt.% steps of the alloy were mixed in a Turbula mixer for 1 h. The preforms with alloy concentrations of 80 and 100 % were hot consolidated at 480oC and closed-die forged at the same temperature. The effect of chemical composition on microstructure and mechanical properties in bending and compression was examined. Bend strength ranged from 400 to 540 MPa, compression strength from 415 to 744 MPa and hardness from 32 to 203 HB. Simulated distribution of component materials for a cross-section of the forging and shapes of the materials were analysed using LARSTRAN/Shape finite element program and are qualitatively comparable with the results obtained by forging.

Crack Separation Energy Rates in Elastic-Plastic Fracture Mechanics

1976 ◽  
Vol 190 (1) ◽  
pp. 571-584 ◽  
Author(s):  
A. P. Kfouri ◽  
K. J. Miller
Keyword(s):  
Fracture Mechanics ◽  
Biaxial Stress ◽  
Separation Energy ◽  
Brittle Crack ◽  
Finite Element Program ◽  
Elastic Plastic ◽  
Theoretical Predictions ◽  
Element Program ◽  
Dimensional Parameters ◽  
Independent Integral

SYNOPSIS The application of Griffith energy concepts to Elastic-Plastic Fracture Mechanics (EPFM) is investigated. An elastic-plastic finite element program is used to calculate the values of the Crack Separation Energy Rate, GΔ, corresponding to a variety of biaxial stress-strain states. The effect of the size of the crack tip plastic zone on the fracture stress is investigated and a relation is established between two non-dimensional parameters φ and ψ . The first parameter φ gives a measure of the ductility of the material while the second parameter ψ is related to the applied stress when brittle fracture occurs. The character of the φ, ψ dependence suggests that when a certain value of the ductility parameter φ is exceeded, brittle crack growth is no longer possible and the mode of crack extension must change to one of a ductile nature. The theoretical predictions of fracture toughness are favourably compared with the results of experiments. Calculated values of GΔ, the stress intensity factor, K, and Rice's path independent integral J are also compared and the applicability of these parameters to brittle, quasi-brittle and ductile fracture is critically discussed.

The Mechanical Properties Analysis of Heterotypic Spatial Plate and Shell Structure Model

2012 ◽  
Vol 256-259 ◽  
pp. 922-925
Author(s):  
Shao Wei Duan ◽  
Peng Zhou ◽  
Xi Bing Hu
Keyword(s):  
Mechanical Properties ◽  
Shell Structure ◽  
Concrete Strength ◽  
Influence Factors ◽  
Structure Model ◽  
Finite Element Program ◽  
Plate And Shell ◽  
Element Program ◽  
Deformation Coefficient ◽  
Elastic Stage

The shape of heterotypic spatial plate and shell structure is irregular, the performance of force is complex, so it is necessary to analyze the stress performance for this heterotypic spatial plate and shell structure, and understand the stress characteristics. By using the finite element program MIDAS to analyze its mechanical properties in elastic stage, and put forward the deformation coefficient of K to embody the deformation performance of spatial plate and shell structure. Through analyzing the influence factors, such as inclination of shell, concrete strength and thickness of shell, to effect mechanical properties of the heterotypic spatial plate and shell structure.

Sign in / Sign up

Export Citation Format

Share Document