Mechanical Engineering Commons^™

An Investigation Of Composite Failure Analyses And Damage Evolution In Finite Element Models, Ann M. Frappier

Open Access Theses

This paper presents a composite conical structure used commonly in flight-qualification testing. This structure’s overall load-displacement behavioral response is characterized. Mixed-mode multidelamination in a layered composite specimen is considered in Abaqus/Explicit through both the Virtual Crack Closure Technique and Cohesive Elements. The Virtual Crack Closure Technique and Cohesive Elements are compared against experimental test results presented in literature. Further, a thorough comparison in which the effects of failure criteria type, through-thickness mesh density, and finite element type on the progressive failure response of this composite assembly is discussed. Lastly, Abaqus/Standard and Helius PFA are compared in order to gain confidence …

Compression Molded Composite Component, Greg Hermansen, Larsson Johnson, Joanne Medrano, Kyle Hammell

Mechanical Engineering

The following final design report outlines the design and fabrication of a carbon fiber compression molded sunglasses case. It intends to guide the development of a future lab activity for a composites undergraduate course at Cal Poly – San Luis Obispo. The activity aims to support an educational investigation in "out-of-autoclave" composites manufacturing methods, such as compression molding, which offer some key benefits over autoclave molding. The methodology behind the creation of a conceptual design, an initial prototype, and a final product is laid out in detail below.

Ultra-Light Bear Canister, Naveen Beasley, Eli Rogers, Cory Wilson, Donald Wood

Mechanical Engineering

A bear canister is the primary tool used by outdoor enthusiasts to protect their food from bears while camping or backpacking. There are many effective products currently on the market, however many are not designed with reduced weight in mind. Hardcore backpackers want to have the lightest gear possible to ease the strain of carrying a large pack for sometimes weeks at a time.

Current bear canisters exist that utilize carbon fiber for weight reduction, however they rely on stock carbon tubes and lack engineering analysis, and no competitor has a fully composite bear canister available. Our sponsor, Nick Hellewell, …

Investigating The Effect Of Carbon Nanotube Functionalization In A Polydimethylsiloxane Composite Through Use Of A Stepped Bar Apparatus, Matthew I. Ralphs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Thermal interface materials (TIMs) are used in transporting heat away from a circuit or electronic module. Composite materials are a popular research area for TIMs because they allow the desired properties to be joined in a composite to take advantage of the best properties from all the constituents involved. The composite selected for this study uses carbon nanotubes (CNT) as the filler and an elastomeric polymer for the matrix, specifically a multiwalled carbon nanotube (MWCNT) / polydimethylsiloxane (PDMS) composite. This study looks at chemical modification (functionalization) of the CNTin an effort to produce a better bond between the CNT and …

Anisotropic Electrical Response Of Carbon Fiber Reinforced Composite Materials, Mohammad Faisal Haider

Theses and Dissertations

Composites materials are often subjected to multi-physical conditions in different applications where, in addition to mechanical loads, they also need to sustain other types of loads such as electrical currents. The multi-physical behavior of composites needs to be understood and analyzed to facilitate new multi-functional material design. An essential first step towards this goal is to understand how multi-physics properties depend on local details (e.g. micro-structure). Composite materials have heterogeneous electrical properties (carbon/epoxy) at the local level that can be different at the global level. To conduct the multi-physics study, the electrical signal is employed to the composite sample for …