Consideration of Parameter Scattering in Thermo-Mechanical Characterization of Advanced Packages

1999 ◽  
Vol 121 (4) ◽  
pp. 282-285 ◽  
Author(s):  
T. Winkler ◽  
A. Schubert ◽  
E. Kaulfersch ◽  
B. Michel
Keyword(s):  
Finite Element ◽  
Life Time ◽  
Electronic Packages ◽  
Element Determination ◽  
Local Material ◽  
Element Simulation ◽  
Geometrical Imperfections ◽  
Element Approach ◽  
Partial Randomness ◽  
Local Material Properties

Much progress has been made in the simulation and verification of the thermo-mechanical behavior of plastic packages. On the other hand, until now there is a lack in the consideration of the scatter or uncertainty, respectively, of certain characteristics. A comparatively large scatter of local material properties or random geometrical imperfections can often be observed within the material compounds of electronic packages. The partial randomness of certain input parameters creates uncertainties in the finite element determination of mechanical quantities which are provided for thermo-mechanical reliability optimization and life time prediction. In the following the STOFEM stochastic finite element approach based on perturbation theory is applied as a part of the finite element simulation. It is used to find out some additional effects arising from uncertainties in the modeling, slightly varying parameters or probabilistic influences, respectively. In a second part of the paper, another approach to the consideration of random variations is discussed. It is based on the randomization of initially deterministic relations.

Thermo-Mechanical Reliability of 3D-integrated Microstructures in Stacked Silicon

2006 ◽  
Vol 970 ◽  
Author(s):  
Bernhard Wunderle ◽  
R. Mrossko ◽  
O. Wittler ◽  
E. Kaulfersch ◽  
P. Ramm ◽  
...  
Keyword(s):  
Finite Element ◽  
Thermal Loading ◽  
New Technology ◽  
Design Guidelines ◽  
Stress And Strain ◽  
Mechanical Reliability ◽  
Local Material ◽  
Element Simulation ◽  
3D Chip Stacking ◽  
Local Material Properties

ABSTRACTThis paper investigates the thermo-mechanical reliability of inter-chip-vias (ICV) for 3D chip stacking after processing and under external thermal loads relevant for the envisaged field of application (mobile, automotive) by Finite Element simulation. First the materials are characterised by nano-indentation to determine elasto-plastic data. Finite Element simulations are used to reproduce these data and to extract local material properties like E-modulus and yield stress. Accumulated plastic strain is used as failure indicator under periodic thermal loading of an ICV. Geometrical, material and process-related parameters are varied to obtain first design guidelines for this new technology. The locations of stress and strain accumulation are given.

A Combined Knowledge-Based and Finite Element Approach to Forging Die Design

1991 ◽  
Author(s):  
Imtiaz Haque ◽  
P. D. Dabke ◽  
Chesley Rowe ◽  
John Jackson
Keyword(s):  
Finite Element ◽  
Mesh Generation ◽  
Die Design ◽  
Knowledge Based System ◽  
Knowledge Based ◽  
Element Simulation ◽  
Regeneration Procedure ◽  
Element Approach ◽  
Forging Die ◽  
Simulation Package

Abstract This paper presents the use of a knowledge-based system to provide the link between computer-aided rule-of-thumb procedures and a finite element simulation package for the design of forging dies. The knowledge-based system automates the mesh generation and regeneration procedure that is traditionally the most cumbersome aspect of such a process. The system is programmed in Prolog, C, and Fortran. It is based on parametric mapping approach and generates 2-D quadrilateral meshes. Results are presented to show its effectiveness in reducing the effort and skill required for conducting forging simulations.

A methodology to consider local material properties in structural optimization

2016 ◽  
Vol 231 (15) ◽  
pp. 2822-2834 ◽  
Author(s):  
Riccardo Cenni ◽  
Matteo Cova ◽  
Giacomo Bertuzzi
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Cast Iron ◽  
Shape Optimization ◽  
Material Properties ◽  
Simulation Software ◽  
Optimization Techniques ◽  
Local Material ◽  
Local Strength ◽  
Local Material Properties

We propose a finite element methodology to consider local material properties for large cast iron components in shape optimization. We found that considering local strength instead of uniform strength within shape optimization brings to different results in terms of safety-cost balance for the same component. It is well known that local mechanical properties of large cast iron components are defined by their microstructure and defects, which locally affect the strength of the components. Considering or not local mechanical properties can dramatically change a component reliability evaluation during its design. Since a typical industrial aim for shape optimization is trying to get the optimal solution in terms of component quality and cost, considering local material properties is even more important than in traditional design process where no optimization techniques are used. We compute solidification process parameters via finite element solidification analysis, and then we exploit experimental correlation between these parameters and ultimate tensile strength to evaluate the local reliability of the finished component under its static loading conditions. We believe that this methodology represents an opportunity to better design casting components when mechanical properties are deeply affected by their production process as described in the provided examples. In these examples, we wanted to minimize casting cost constrained by a target reliability and we get component cost reduction by considering local material properties. Future research will address the problem of using dedicated casting simulation software instead of general purpose finite element analysis software to compute solidification analysis and then introducing fatigue analysis and correlation between fatigue material properties and casting process output variables.

A BOUNDARY-LAYER APPROACH TO STRESS ANALYSIS IN THE SIMPLE SHEARING OF RUBBER BLOCKS

2012 ◽  
Vol 85 (1) ◽  
pp. 108-119 ◽  
Author(s):  
Cornelius O. Horgan ◽  
Jeremiah G. Murphy
Keyword(s):  
Finite Element ◽  
Normal Stress ◽  
Boundary Layers ◽  
Incompressible Material ◽  
Complex Stress ◽  
Element Simulation ◽  
The Face ◽  
Element Approach ◽  
Stress Boundary Condition ◽  
Stress Boundary

Abstract Rubbers are usually modeled as being perfectly incompressible. In the simple shear of rubber blocks, the normal stress components, therefore, contain an arbitrary constant pressure term to be determined from the boundary conditions. There is therefore a fundamental ambiguity in the determination of this pressure because the normal stresses are expected to be identically zero on different faces of the sheared block. It is proposed here that the stress distribution near a face should be determined by the normal stress boundary condition at that face and that this distribution is valid only within a short distance from the face, giving rise to boundary layers at the faces of the sheared block. At the intersection of these boundary layers it will be assumed that the stress is additive. It is further assumed that the stresses within the bulk of the material should be determined by treating the perfectly incompressible material as equivalent to a slightly compressible material. The form of slight compressibility adopted here is that usually assumed in the finite element simulation of rubbers. These reasonable assumptions give rise to a complex stress pattern within the block. The results are qualitatively similar to results obtained by other authors on using a finite element approach for a neo-Hookean material. The possible occurrence of cavitation at the corners of the block is also examined.

scholarly journals Finite Element Modeling of Micro-Particle Separation Using Ultrasonic Standing Waves

2014 ◽  
Author(s):  
Süleyman Büyükkoçak ◽  
Barbaros Çetin ◽  
Mehmet Bülent Özer
Keyword(s):  
Finite Element ◽  
Acoustic Waves ◽  
Real Life ◽  
The Finite Element Method ◽  
Channel Geometry ◽  
Micro Particles ◽  
Element Simulation ◽  
Element Approach ◽  
Fluid Channel ◽  
Starting Location

Acoustophoresis which means separation of particles and cells using acoustic waves is becoming an intensive research subject. The method is based on inducing an ultrasonic compression standing wave inside a microchannel. A finite element approach is used to model the acoustic and electro-mechanical behavior of the piezoelectric material, the micro-channel geometry as well as the fluid inside the channel. The choices of silicon and PDMS materials are investigated as the chip materials for the resonator. A separation channel geometry which is commonly used in the literature is implemented in this study and the fluid flow inside the microchannel geometry is simulated using computational fluid dynamics. The acoustic field inside the fluid channel is also be simulated using the finite element method. For the separation process to be successful micro-particles of different diameter groups should end up in different channels of the micro-separator. In order to simulate real life scenarios, each particle size group have a size distribution within themselves. For realistic simulation results the particles will be released into the micro separator from a different starting locations (starting location distribution). The results of this Monte-Carlo based finite element simulation approach will be compared with the reported experimental results.

Analysis of magnetic force and dynamic characteristic for non-contact permanent magnet linear drive device

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1337-1345
Author(s):  
Chuan Zhao ◽  
Feng Sun ◽  
Junjie Jin ◽  
Mingwei Bo ◽  
Fangchao Xu ◽  
...  
Keyword(s):  
Finite Element ◽  
Permanent Magnet ◽  
Dynamic Characteristic ◽  
Driving Force ◽  
Magnetic Circuit ◽  
Response Speed ◽  
Computation Method ◽  
Element Analysis ◽  
Element Simulation ◽  
The Relationship

This paper proposes a computation method using the equivalent magnetic circuit to analyze the driving force for the non-contact permanent magnet linear drive system. In this device, the magnetic driving force is related to the rotation angle of driving wheels. The relationship is verified by finite element analysis and measuring experiments. The result of finite element simulation is in good agreement with the model established by the equivalent magnetic circuit. Then experiments of displacement control are carried out to test the dynamic characteristic of this system. The controller of the system adopts the combination control of displacement and angle. The results indicate that the system has good performance in steady-state error and response speed, while the maximum overshoot needs to be reduced.

Sign in / Sign up

Export Citation Format

Share Document