Engineering Commons^™

Failure Simulations At Multiple Length Scales In High Temperature Structural Alloys, Chao Pu

Doctoral Dissertations

A number of computational methodologies have been developed to investigate the deformation and damage mechanism of various structural materials at different length scale and under extreme loading conditions, and also to provide insights in the development of high-performance materials.

In microscopic material behavior and failure modes, polycrystalline metals of interest include heterogeneous deformation field due to crystalline anisotropy, inter/intra grain or phase and grain boundary interactions. Crystal plasticity model is utilized to simulate microstructure based polycrystalline materials, and micro-deformation information, such as lattice strain evolution, can be captured based on crystal plasticity finite element modeling (CPFEM) in ABAQUS. The comparison …

Spare Parts On Demand Using Additive Manufacturing : A Simulation Model For Cost Evaluation., Stefan Jedeck

Electronic Theses and Dissertations

Little is known about the impact of additive manufacturing in the spare part supply chain. A few studies are available, but they focus on specific parts and their applications only. A general model, which can be adapted to different applications, is nonexistent. This dissertation proposes a decision making framework that enables an interested practitioner/manager to decide whether using additive manufacturing to make spare parts on demand is economical when compared to conventional warehousing strategy. The framework consists of two major components: a general discrete event simulation model and a process of designing a wide range of simulation scenarios. The goal …

Numerical Simulations Of Twin Formation And Extension In Thin Face-Centred Cubic Metallic Films, Romuald Bejaud, Sandrine Brochard, Julien Durick

Nanomechanical Testing in Materials Research and Development V

The basic mechanisms of plasticity in face-centred cubic materials are now well known in bulk materials. However, several experimental studies have shown that at the nanoscale, some of its mechanisms can induce surprising mechanical properties when compared to bulk behaviour. The formation and extension of twins in metallic nanowire can, for example, generate super-plasticity [1] or the presence of growth nano-twins within a material can lead to strengthening effects [2]. Atomic simulations are particularly adapted for studying the plasticity mechanisms at play, since they allow their visualization at the atomic scale.

While many atomistic simulations studies have been focused on …

Thermal And Mechanical Properties Of Polymers Using Molecular Dynamics, Daniel Glass, Alejandro Strachan, Lorena Alzate-Vargas, Chunyu Li, Benjamin Haley

The Summer Undergraduate Research Fellowship (SURF) Symposium

Polymer systems have gained attention during the past years because of their technological and industrial applications. Simulations, particularly molecular dynamics, are very useful for exploring properties of amorphous polymers, without using experiments. Our goal is to create a readily-available tool that will perform MD simulations in order to get thermal and mechanical properties (Glass transition temperature, Young Modulus) of the polymers. The work that has been done will be part of a tool to help people to learn about polymer properties including Glass Transition Temperature. We model some polymers at a scale of 10,000 atoms. The tool uses LAMMPS to …

Thermodynamic And Kinetic Simulation Of Transient Liquid-Phase Bonding, Brad Allen Lindner

Theses and Dissertations

ABSTRACT

THERMODYNAMIC AND KINETIC SIMULATION OF TRANSIENT LIQUID-PHASE BONDING

by

Brad Lindner

The University of Wisconsin-Milwaukee, 2015

Under the Supervision of Professor Benjamin C. Church

The use of numeric computational methods for the simulation of materials systems is becoming more prevalent and an understanding of these tools may soon be a necessity for Materials Engineers and Scientists. The applicability of numerical simulation methods to transient liquid-phase (TLP) bonding is evaluated using a type 316L/MBF-51 material system. The comparisons involve the calculation of bulk diffusivities, tracking of interface positions during dissolution, widening, and isothermal solidification stages, as well as comparison of …

Fundamental Problems In Porous Materials: Experiments & Computer Simulation, Zhanping Xu

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Porous materials have attracted massive scientific and technological interest because of their extremely high surface-to-volume ratio, molecular tunability in construction, and surface-based applications. Through my PhD work, porous materials were engineered to meet the design in selective binding, self-healing, and energy damping. For example, crystalline MOFs with pore size spanning from a few angstroms to a couple of nanometers were chemically engineered to show 120 times more efficiency in binding of large molecules. In addition, we found building blocks released from those crystals can be further patched back through a healing process at ambient and low temperatures down to -56 …

Nanohub.Org: A Gateway To Undergraduate Simulation-Based Research In Materials Science And Related Fields, Tanya A. Faltens, Peter A. Bermel, Amanda Buckles, K Anna Douglas, Alejandro H. Strachan, Lynn K. Zentner, Gerhard Klimeck

Birck and NCN Publications

Our future engineers and scientists will likely be required to use advanced simulations to solve many of tomorrow's challenges in nanotechnology. To prepare students to meet this need, the Network for Computational Nanotechnology (NCN) provides simulation-focused research experiences for undergraduates at an early point in their educational path, to increase the likelihood that they will ultimately complete a doctoral program. The NCN summer research program currently serves over 20 undergraduate students per year who are recruited nationwide, and selected by NCN and the faculty for aptitude in their chosen field within STEM, as well as complementary skills such as coding …