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Articles 121 - 150 of 394
Full-Text Articles in Materials Science and Engineering
Investigation Of Outlife Time On The Environmental Durability Of P2-Etched, Adhesively-Bonded Aluminum Alloys Using The Astm Wedge Test, Daniel Gross, Corey Sutton
Investigation Of Outlife Time On The Environmental Durability Of P2-Etched, Adhesively-Bonded Aluminum Alloys Using The Astm Wedge Test, Daniel Gross, Corey Sutton
Materials Engineering
P2 etchant is an environmentally-friendly aluminum etchant which has the potential to replace the Forest Products Laboratory (FPL) etchant as the industry standard. Environmental durability of adhesively-bonded aluminum surfaces etched using a paste version of the P2 etchant were tested using the Boeing-developed wedge test (ASTM D3762 - 03(2010)). This project specifically aimed to examine the relationship between outlife time (the time between etching and adhering) and the ability of bonded aluminum samples to pass the wedge test. Two aluminum alloys, 2024-T3 and 7075-T6, were wedge tested and the etched surfaces examined with an atomic force microscope (AFM) and a …
Improving Surface Roughness Of Optically Telegraphed Composite Laminations, Michael Smith
Improving Surface Roughness Of Optically Telegraphed Composite Laminations, Michael Smith
Materials Engineering
In collaboration with Watson Furniture, this project seeks to identify the cause of surface roughness on composite panels processed into commercial furnishings. The surface roughness was examined and measured using an optical microscope, a scanning electron microscope (SEM), and a profilometer. The SEM and optical microscope provided qualitative data on the surface roughness as well as the film build of each layer. After an initial characterization of the manufactured samples provided by Watson Furniture, additional samples were fabricated for testing using different manufacturing processes than those used by Watson Furniture. These samples were constructed in-house using raw materials provided by …
Effect Of Hydrogen Pick-Up And Release Behavior On The Tensile Properties Of Electroplated 4340m High-Strength Steel, Blake Daylor, Joshua Fisher, Alan Michelen Ruiz
Effect Of Hydrogen Pick-Up And Release Behavior On The Tensile Properties Of Electroplated 4340m High-Strength Steel, Blake Daylor, Joshua Fisher, Alan Michelen Ruiz
Materials Engineering
Hydrogen embrittlement of high-strength steel (4340M) was quantified through tensile testing and fractography (SEM). Three types of samples were obtained: rotating beam fatigue specimens, round (notched) tensile specimens, and flat panel specimens. In addition, three different plating types were analyzed (Ni, Cr, Cd-Ti) with a set of samples that was shot peened and a set that was not. Since some of the samples went through a hydrogen relief bake, another factor in our experiment was the amount of time it took for the samples to reach the baking process after they were electroplated (bake delay). There were three levels of …
Controlling Grain Size In Cold Worked And Annealed 1100 Aluminum To Optimize Ductility In Rocket Diaphragm Systems, Ryan Lewis, Bryce Simmons, Jessica Williams
Controlling Grain Size In Cold Worked And Annealed 1100 Aluminum To Optimize Ductility In Rocket Diaphragm Systems, Ryan Lewis, Bryce Simmons, Jessica Williams
Materials Engineering
Liquid propellant rocket diaphragms require extreme ductility. 1100 Aluminum is used for its high ductility, but the post-processing cold work and subsequent anneal result in excessively large grains. The effect of heat treatment and cold work on grain size in 1100 aluminum was explored. The samples were cold worked to 0, 5, 10, 15 and 30% using tensile elongation. The samples were then heat treated per AMS 2770 with either a "Steel Conduction" (1000 – 1150°F/min) or a "Production" (16 – 18°F/min) heating rate. The grain size of the samples were measured using the mean lineal intercept method. The grain …
Grain Orientation Effects On The Rotating-Bending Fatigue Properties Of Forged 7050-T7452 Aluminum Alloy, Matt Cristler, Jonas Zhang
Grain Orientation Effects On The Rotating-Bending Fatigue Properties Of Forged 7050-T7452 Aluminum Alloy, Matt Cristler, Jonas Zhang
Materials Engineering
In order to investigate the effects of grain orientation on the high cycle fatigue properties of 7050-T7452 aerospace grade aluminum, rotating-bending fatigue tests were performed on longitudinal (LG) and short transverse (ST) specimens taken from two sample sets (Method A and Method B) of open die forged 7050 aluminum. The fatigue specimens were machined to a 0.2" gage diameter and 4" length and subsequently hand polished to a mirror finish to minimize potential crack initiation sites. The tests were conducted on a Fatigue Dynamics RBF-300 HT tester in the fully reversed loading condition, with stress levels varying from 20 ksi …
Life Cycle Assessment Of Paper Versus Electronic Assignment Submission In Cal Poly's Materials Engineering, Patrick Mcdonnal
Life Cycle Assessment Of Paper Versus Electronic Assignment Submission In Cal Poly's Materials Engineering, Patrick Mcdonnal
Materials Engineering
Both hard and soft copy submission of assignments make an impact on the environment to produce the final product in terms of energy consumption and carbon emissions; an investigation was conducted as to which method is less environmentally impactful. Student disposition towards each assignment submission method was also investigated because it is associated with learning efficacy. A survey was conducted in Cal Poly’s Materials Engineering Department to determine the contributing components to the environmental impact of paper and electronic assignments, as well as the students’ disposition towards each of them. Contributing components are man-made products used by a student to …
Life Cycle Assessment And Comparison Of Magnesium Oxide Nanoparticles Prepared By Aqueous And Microwave Synthesis Methods, Jesse Cartland
Life Cycle Assessment And Comparison Of Magnesium Oxide Nanoparticles Prepared By Aqueous And Microwave Synthesis Methods, Jesse Cartland
Materials Engineering
Abstract: Magnesium oxide nanoparticles are being used increasingly as catalysts for organic synthesis, fuel oil additives, and CO2 adsorbents. There are many ways to produce magnesium oxide nanoparticles, but there is little information available regarding the environmental costs of production. As demand for environmentally friendly materials increases, it is important to understand environmental impact differences between various production methods. This study will compare the differences in embodied energy and global warming potential (GWP) between two synthesis methods: microwave combustion synthesis (microwave synthesis) and oxidation of magnesium hydroxide (aqueous synthesis). The resulting nanoparticles were characterized using scanning electron microscopy (SEM), …
Manufacturing And Characterization Of Poly (Lactic Acid)/Carbon Black Conductive Composites For Fdm Feedstock: An Exploratory Study, Dylan Fitz-Gerald, Justin Boothe
Manufacturing And Characterization Of Poly (Lactic Acid)/Carbon Black Conductive Composites For Fdm Feedstock: An Exploratory Study, Dylan Fitz-Gerald, Justin Boothe
Materials Engineering
This exploratory study developed methods of manufacturing and characterizing the electrical properties of small batches of conductive composite feedstock for the Fused Deposition Modeling (FDM) manufacturing process, commonly known as 3D printing. We utilized a solution casting process of Poly(lactic acid) (PLA) (Grade 4043D, NatureWorks, LLC.) and Carbon Black (CB) (Vulcan® XC72, Cabot Corp.) in chloroform. The resulting composite precursor was cryogenically treated with liquid nitrogen and milled in a coffee grinder in order to achieve particles that could be fed into the extruder. Composite precursors were dried in a vacuum oven at an elevated temperature of 38°C. Filaments were …
An Investigation Of Incipient Melting During Solution Heat Treatment Of 7050 Aluminum Forgings And Its Effect On Corrosion Properties, Thomas Kilkenny
An Investigation Of Incipient Melting During Solution Heat Treatment Of 7050 Aluminum Forgings And Its Effect On Corrosion Properties, Thomas Kilkenny
Materials Engineering
7050 alloy (6.2Zn-2.3Mg-2.3Cu-0.12Zr) is a structural aluminum alloy commonly used in the aerospace industry. Its rich chemistry makes it susceptible to incipient melting. Incipient melting is a phenomenon where areas with high local alloy content melt before the rest of the material. This can cause a degradation of mechanical and corrosion properties. A six by four factor solution heat treatment trial was conducted. Six solution heat treatment temperatures, 890- 940°F in 10°F increments, and four times, 1, 2, 4, and 6 hours, were used. Incipient melting was observed in the 910°F, 6 hour solution heat treatment and all 920-940°F solution …
Analysis Of Shear Strength Variance Of Ph 15-7 Mo Blind Rivet Stems For Aerospace Applications, Miles Macarthur, Kent C. Majewski
Analysis Of Shear Strength Variance Of Ph 15-7 Mo Blind Rivet Stems For Aerospace Applications, Miles Macarthur, Kent C. Majewski
Materials Engineering
This project attempts to reduce manufacturing costs incurred to Cherry Aerospace by variance in material properties. To track and predict the shear strength of PH 15-7 Mo stainless steel rivet stems throughout the heat treatment process, samples were taken from several steps in the manufacturing process and experimental heat treatments were performed across a range of temperatures. The supplied rivet stems were heat treated for four hours at temperatures from 520°C to 560°C, in increments of 10°C. Double shear testing in accordance with ASTM 1312-13A revealed that there is no apparent correlation between the strength of the supplied wire and …
Effect Of Heat Treatment On The Mechanical Properties In Natural Bamboo, Austin Levy, Mackenzie Kirkpatrick
Effect Of Heat Treatment On The Mechanical Properties In Natural Bamboo, Austin Levy, Mackenzie Kirkpatrick
Materials Engineering
Previous studies have shown that heat treatments have the ability to improve mechanical strength and stiffness in hardwood species. Compared to structural hardwoods, bamboo is a more sustainable and globally viable renewable resource. Therefore, Bambusoides vivax (timber bamboo) culms were fabricated into flat, rectangular cross-section samples with varying cellulose content to be heat treated and tested for mechanical properties. All samples were heat treated (HT) twice. The first HT was a normalization of all samples at 103 +/- 3 °C. The second HT was performed at various times and temperatures ranging from 130°C to 170°C for 0.5 to 3 hours. …
Minimizing Sheet Resistance Of Organic Photovoltaic Cell Top Contact Electrode Layer: Silver Nanowire Concentration Vs. Conductive Polymer Doping Concentration, Caitlyn Cook
Materials Engineering
The top contact electrode layers of nine organic photovoltaic cells were prepared with two varying factors: three Silver nanowire (AgNW) densities deposited on a conductive polymer doped with three concentrations. Silver’s low sheet resistance of 20-Ω/sq is hypothesized to lower the sheet resistance of the anode layer and thus enhance the overall efficiency of the cell. Four-point probe measurements indicated that increasing AgNW density in the top contact electrode layer of an organic photovoltaic cell significantly reduces sheet resistance from 52.2k-Ω/sq to 18.0 Ω/sq. Although an increase in doping concentration of the conductive polymer reduced sheet resistance in low AgNW …
Tensile Test Design To Measure Interlayer Adhesion In Investment Casting Shells For Spalling Mitigation, Shelby Boyd, Alex Miller, Jameson Senger
Tensile Test Design To Measure Interlayer Adhesion In Investment Casting Shells For Spalling Mitigation, Shelby Boyd, Alex Miller, Jameson Senger
Materials Engineering
We designed a tensile test fixture for a 112 lbf capacity Instron load frame that imparts a normal force on the face of a button epoxied to an investment casting shell sample, delaminating the shell area attached to the button. Using a green standard shell (Group 1), a partially fired standard shell (Group 2), and a green shell with a different third coat (Group 3), we verified that the fixture can measure differences in strength between sample groups. We attached steel buttons to leveled samples with 0.05 mL of Hysol-Loctite 9340 epoxy, let it cure for 48 hours, and tested …
Effect Of Time Delay Between Etching And Adhesive Bonding (“Outlife” Time) On Lap-Shear Strength Of Aluminum Alloys Using Environmentally-Friendly P2 Etch, Josh Barkhimer, Matthew Erich, Gokul Nair
Effect Of Time Delay Between Etching And Adhesive Bonding (“Outlife” Time) On Lap-Shear Strength Of Aluminum Alloys Using Environmentally-Friendly P2 Etch, Josh Barkhimer, Matthew Erich, Gokul Nair
Materials Engineering
Raytheon Company currently uses a Forest Products Laboratory (FPL) paste etchant for preparing aluminum surfaces for adhesive bonding, and FPL is a source of hazardous hexavalent chromium. The goal of this study was to evaluate a less-toxic P2 paste etchant as a possible replacement. Coupons of 2024-T3, 6061-T6, and 7075-T6 grades of aluminum alloy were solvent-degreased, abrasively cleaned, and etched at room temperature using P2 paste following a strict protocol adopted from Raytheon. Coupons were then left exposed to air for assigned time intervals (or “outlife” times) of 0, 1, 4, 8, 16, and 63 or 72 hours. The aluminum …
Effects Of Composition And Solid Solution Strengthening On The Compression Strength Of Iron-Based Hardfacing Alloys, Tyler Wiggins, Samuel Garrison-Terry
Effects Of Composition And Solid Solution Strengthening On The Compression Strength Of Iron-Based Hardfacing Alloys, Tyler Wiggins, Samuel Garrison-Terry
Materials Engineering
Three iron-based hardfacing alloys were fabricated to have a tungsten strengthened matrix with varying compositions of 10-15, 20, and 30 wt% tungsten/chrome boride content. The fourth sample was fabricated to have a molybdenum solid solution strengthened matrix with 10-15 wt% W/Cr Boride content. This project focuses on the compressive strength of iron-based hardfacing alloys. Preliminary compression tests with Scoperta iron-based hardfacing alloys showed a need for sample dimension reduction due to compressive loads that could not be met by a 50 kN maximum capacity mechanical testing system. The preliminary tests showed compressive strengths exceeding 2340 MPa. Samples of the current …
Electrochemical Testing Of Aluminum-Lithium Alloys 2050, 2195, And The Current Aerospace Industry Standard 7075 To Measure The Galvanic Corrosion Behavior With Ti-6al-4v, Trent Duncan, Kevin Knight
Electrochemical Testing Of Aluminum-Lithium Alloys 2050, 2195, And The Current Aerospace Industry Standard 7075 To Measure The Galvanic Corrosion Behavior With Ti-6al-4v, Trent Duncan, Kevin Knight
Materials Engineering
This project aimed to characterize the electrochemical behavior of four different aluminum alloys, and determine how much galvanic corrosion would occur when each alloy was coupled to Ti-6Al-4V. The particular alloys tested were 2050-T3, 2050-T852, 2195-T852, and 7075-T7352. These alloys were tested to determine the effects of aging, and adding lithium, to the corrosion behavior of aluminum alloys. Potentiodynamic polarization curves were generated using the Parstat 2273 potentiostat in accordance with ASTM standard G5, and corrosion analysis software was used to produce Tafel fit lines, which determined the open circuit potential (Ecorr) of each sample. Nine tests were …
Measuring And Increasing The Suspension Time Of Lanthanide Oxysulfide Particles With Modifiers Via Fluorescence For Use In Anti-Counterfeiting Applications, Joe Dei Rossi, Tyler Dinslage, Tyler Schelling
Measuring And Increasing The Suspension Time Of Lanthanide Oxysulfide Particles With Modifiers Via Fluorescence For Use In Anti-Counterfeiting Applications, Joe Dei Rossi, Tyler Dinslage, Tyler Schelling
Materials Engineering
No abstract provided.
Mechanical Testing Of Multi-Construction Composite Tubes For Use In Fly Fishing Rods, Macormik Hopen
Mechanical Testing Of Multi-Construction Composite Tubes For Use In Fly Fishing Rods, Macormik Hopen
Materials Engineering
A testing protocol was established for measuring the flexure properties of thin-walled tubes constructed of a composite mixture of glass and carbon fibers and epoxy resin for use in Fly Fishing rods. Standard three point bend tests were conducted in accordance with ASTM standard D7329-13 with a span length of six inches. All samples were of the sample length and diameter, allowing direct comparison of the maximum loads reached before failure, which are directly indicative of the Modulus of Rupture (MOR). Two constructions were tested both containing the same unidirectional fiber but with different support structure. These tubes were tested …
Molecular Dynamics Investigation Of The Arabinan-Cellulose Interface For Cellulose Nanocomposite Applications, Luke Thornley
Molecular Dynamics Investigation Of The Arabinan-Cellulose Interface For Cellulose Nanocomposite Applications, Luke Thornley
Materials Engineering
Atom level computer simulations of the arabinan and cellulose interface were performed to better understand the mechanisms that give arabinan-cellulose composites (ArCCs) their strength with the goal to improve man-made ArCCs. The molecular dynamics (MD) software LAMMPS was used in conjunction with the ReaxFF/c force field to model the bond between cellulose and arabinan. A cellulose nanocrystal with dimensions 51 x 32 x 8 Å was minimized with various weight percent of water, 0%, 3%, 5%, 8%, 10%, and 12%. After the system was equilibrated for at least 100,000 femtoseconds, an arabinan molecule composed of 8 arabinose rings was added …
Characterization Of Laser Deposited Ti-6al-4v To Nb Gradient Alloys, Clincy Cheung
Characterization Of Laser Deposited Ti-6al-4v To Nb Gradient Alloys, Clincy Cheung
Materials Engineering
An alloy was fabricated with Ti-6Al-4V and Nb powder using laser deposition (LD) to form a compositional gradient. The gradient was deposited, starting with Ti-6Al-4V powder, onto a forged Ti-6Al-4V substrate in an Argon environment. Niobium (Nb) composition increased by 4-at.% with each layer deposited until the composition reached 100-at.% Nb. This process yielded steep thermal gradients and affected the microstructure and mechanical properties across the compositional gradient. To observe the microstructural changes in the alloy, an etched gradient was viewed with optical microscopy at 1000x, where the grain structure was observed to be an acicular α phase at 100-at.% …
Investigating The Cause Of Unique Mechanical Behavior In Platinum Alloy Guidewire Tips, Evan Borgeson, Alfred Rosen
Investigating The Cause Of Unique Mechanical Behavior In Platinum Alloy Guidewire Tips, Evan Borgeson, Alfred Rosen
Materials Engineering
The platinum alloy used by Abbott Vascular in guidewire tips exhibits a yielding behavior characterized by an abrupt transition from elastic to plastic zones and high ductility. This yielding behavior was hypothesized to be a result of one of three structural phenomena: ordering, solute strain aging, or interstitial strain aging. To test for these strengthening mechanisms in the wire, X-ray diffraction analysis, heat treatments, and tensile testing were completed. The wire has a diameter of 0.0025 inches and was supplied in two forms, the final stress relieved state, and as-drawn from the production line. Heat treatments were performed at 130 …
Analysis Of Compression Creep Deformation Of 7050 Aluminum Large Scale Open Die Forgings During The Solution Heat Treatment Process, Ashley Lopez, Elysha Cole
Analysis Of Compression Creep Deformation Of 7050 Aluminum Large Scale Open Die Forgings During The Solution Heat Treatment Process, Ashley Lopez, Elysha Cole
Materials Engineering
A stress, ranging from 104.17 to 166.67 psi, was applied to 0.5 in diameter cylindrical samples of 7050 aluminum using a manufactured fixture that applies stress using an indenter with a diameter of 0.127 in. The stress range used replicates the stresses produced on large scale forgings weighing up to 4000 lbs. We chose a maximum, medium and low stress as our stress parameters. The samples were placed into the fixture for stability then placed in a furnace heated to 890°F which is the solution heat treatment temperature for 7050 aluminum. The heat treatment times varied between 4 and 24 …
Effects Of Initial Forging Temperature, Cooling Rates, And Carbon Content On Primary Alpha Formation In Ti-6al-4v, James Tillman, Hui Wei
Effects Of Initial Forging Temperature, Cooling Rates, And Carbon Content On Primary Alpha Formation In Ti-6al-4v, James Tillman, Hui Wei
Materials Engineering
Ti-6Al-4V is an alpha-beta titanium alloy system, which contains both alpha and beta phases at room temperature. Both alpha and beta phases provide Ti-6Al-4V a range of different properties for a range of applications. In order to improve the energy efficiency and better satisfy customers’ requirements of less than 52% primary alpha phase, Weber Metals sponsored this project to study the effects of carbon content, forging temperature, and cooling rates on primary alpha formation in Ti-6Al-4V alloys. There has been a lot of discussion as to whether or not carbon, a known alpha stabilizer, will affect the microstructure in small …
Improving Product Design By Predicting Flexural Strength Of A Honeycomb Core Sandwich Panel Composite Using Ply Tensile Strength, Justin Lui, Javal Patel
Improving Product Design By Predicting Flexural Strength Of A Honeycomb Core Sandwich Panel Composite Using Ply Tensile Strength, Justin Lui, Javal Patel
Materials Engineering
The use of composite sandwich panels has increased in the aerospace industry. Prediction of a theoretical composite construction's flexural properties is important for efficient composite product designs. Utilizing the four point flexure geometry defined by Zodiac Aerospace, Santa Maria, CA, a mechanical model was derived to predict the flexural behavior of a theoretical honeycomb core sandwich composite using laminate tensile properties. The most common failure mode of Zodiac Aerospace’s four point bend test is a failure in tension of the bottom laminate. Given this information, ASTM D3039 (Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials) was chosen …
Elevated Temperature Effects On The Mechanical Properties Of Age Hardened 6xxx Series Aluminum Alloy Extrusions, Rachael Donovan, Rose Fortune, Robert Trout
Elevated Temperature Effects On The Mechanical Properties Of Age Hardened 6xxx Series Aluminum Alloy Extrusions, Rachael Donovan, Rose Fortune, Robert Trout
Materials Engineering
The purpose of this project is to determine if over-aging of aluminum causes the yield or tensile strength to fall below the minimum strength values set by the aluminum industry. Extruded aluminum alloys, 6061-T6, 6063-T6, and two proprietary alloys, HS6X-T6 and RX82-T6, were exposed to reheating treatments at extended times and temperatures. The three temperatures were 350°F, 390°F, and 425°F. The times of reheat increased logarithmically from 30 minutes to 64 hours. The samples were tensile tested to determine the tensile strength and yield strength. Statistical methods helped model the behavior of yield and tensile strength as a function of …
Measuring Performance Of Paint Coating Via Laboratory And Field Testing, Eugene Leung, Rocco Lattanzio
Measuring Performance Of Paint Coating Via Laboratory And Field Testing, Eugene Leung, Rocco Lattanzio
Materials Engineering
No abstract provided.
Second Generation Design Of An Operator Independent Teflon Coating Adhesion Tester For Coronary Guidewires, Garrett L. Wong
Second Generation Design Of An Operator Independent Teflon Coating Adhesion Tester For Coronary Guidewires, Garrett L. Wong
Materials Engineering
No abstract provided.
Electrochemical Characterization Of Precious Metal Braze Alloys Using Potentiodynamic Polarization, Maxwell Glen Martin, Mason Gregory Morgan, Matthew David Vance
Electrochemical Characterization Of Precious Metal Braze Alloys Using Potentiodynamic Polarization, Maxwell Glen Martin, Mason Gregory Morgan, Matthew David Vance
Materials Engineering
This study aimed to characterize the electrochemical behavior of six precious metal braze alloys by performing potentiodynamic polarization tests (ParStat 2273) based on ASTM Specifications G5 and G59. To determine the extent to which the alloys will contribute to galvanic corrosion in a marine environment (3.5 wt% NaCl), corrosion analysis software was used to produce fitted Tafel lines to determine the open circuit potential, Voc, for each alloy. The Voc values for the alloys were found to be -66.58 mV for Gold ABA, 13.01 mV for Nicoro®, -39.00 mV for Nioro®, 23.4 mV …
Fabrication And Testing Of Arabinan Cellulose Nanocomposites, Ross Johnson, Austin Rosso, Nick Semansky
Fabrication And Testing Of Arabinan Cellulose Nanocomposites, Ross Johnson, Austin Rosso, Nick Semansky
Materials Engineering
Inspired by the structure and composition of cactus spines found in nature, arabinan-cellulose nanocomposites were fabricated into thin films and tested for mechanical stiffness. The composites consisted of varying amounts of nanocrystalline cellulose reinforcement suspended in an arabinan matrix. Both materials are polysaccharides and are known to be biodegradable and food safe. The thin film samples were tensile tested using a dynamic mechanical analysis machine both as-cast and after a heat-treatment. The heat treatment of the arabinan itself resulted in an order of magnitude increase in stiffness, while the cellulose reinforced composites increased roughly six fold. The arabinan-50 wt% cellulose …
A Process Development Study On Reducing The Anisotropy While Maintaining The Strength Of Extruded Aluminum Alloy 2195 Through Heat Treatment, Theodore James Arehart
A Process Development Study On Reducing The Anisotropy While Maintaining The Strength Of Extruded Aluminum Alloy 2195 Through Heat Treatment, Theodore James Arehart
Materials Engineering
The purpose of this study was two-fold: develop an aging curve for extruded 2195 aluminum and test the magnitude of the anisotropy in the extrusion throughout the aging process. Two aging curves were developed, one at 290oF and the other at 320oF, through hardness tests of aged samples. The hardness was found to change, from approximately 72 HRB to 90 HRB, within the first 6 hours and not change more than 2 HRB in the 42 hours following. It was determined that the 320oF temperature was more promising due to faster aging time, and …