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Articles 31 - 60 of 83
Full-Text Articles in Engineering
Effect Of Composition And Build Direction On Additively Manufactured Hastelloy X Alloys, Justin A. Spitzer, Jeffrey T. Schloetter, Sarah Zerga
Effect Of Composition And Build Direction On Additively Manufactured Hastelloy X Alloys, Justin A. Spitzer, Jeffrey T. Schloetter, Sarah Zerga
Materials Engineering
Microcracking has caused premature failure and reduction in properties in additively manufactured (AM) Hastelloy X. The purpose of this research is to meet or exceed the mechanical properties of wrought Hastelloy X by modifying the composition and build direction of Hastelloy X manufactured using Direct Metal Deposition (DMD). Tensile testing, scanning electron microscopy (SEM), and metallography were performed on the samples. ANOVA was used to analyze the dependence that the properties had on build direction and composition. The nominal composition wrought samples had a yield strength of 310.1 MPa and a 60.79% Elongation. Alloy P60-X18 in a horizontal build had …
Tensile Properties Of High-Strength Connecting Rod Bolts, Leland K. Lam
Tensile Properties Of High-Strength Connecting Rod Bolts, Leland K. Lam
Materials Engineering
Oliver Racing Parts (ORP) is looking to optimize the manufacturing process for high-strength connecting rod bolts. A high yield strength is desired for the bolts because deformation would result in a loss of engine performance. A high tensile strength is also necessary to prevent catastrophic failure if deformation occurs. A high ductility as a proxy for toughness is attractive for resisting crack nucleation and growth during cyclic loading. Bolts were made of MP35N, a nickel-cobalt multiphase alloy; MLX-17, a precipitation hardenable stainless steel; 8740, a low alloy steel; and H11, a chromium hot-work tool steel. The temperature of the most …
Characterization Of Slm Printed 316l Stainless Steel And Investigation Of Microlattice Geometry, Finley H. Marbury
Characterization Of Slm Printed 316l Stainless Steel And Investigation Of Microlattice Geometry, Finley H. Marbury
Materials Engineering
The goal of this project was firstly to characterize Cal Poly’s SLM printed 316L stainless steel. SEM analysis showed Cal Poly’s as-printed 316L material to have a cellular dendritic microstructure containing mostly austenite and a small amount of δ-ferrite. After being heat treated to eliminate warp, its yeild and ultimate tensile strength were on par with the literature, however higher modulus and lower elongation were observed. XRD analysis confirmed residual stresses in the material, and that grains are preferentially oriented in both heat treated and non heat treated samples. The amount of porosity in the material was found to be …
Straightening Of Investment Casting Ni-Based Superalloys, Silvia Squillaci, Janessa Cabrera
Straightening Of Investment Casting Ni-Based Superalloys, Silvia Squillaci, Janessa Cabrera
Materials Engineering
Samples belonging to four different designs of afterburner flaps, available in the as-cast, solutionized and aged conditions, underwent 4-point bend testing to fracture to investigate straightening. The average maximum load values of the second design samples in the as-cast, solutionized and aged conditions were respectively 33 kN, 29 kN and 27 kN. Regarding the fourth design samples, the average maximum load for the as-cast, solutionized and aged conditions were respectively 23 kN, 28 kN, and 25 kN. The other parameter measured during testing was the maximum extension at fracture. All as-cast samples belonging to the second design fractured at values …
Kinked Tensile Behavior Of Cold Worked Nitinol, Grant R. Caraway, Samuel J. Canovas
Kinked Tensile Behavior Of Cold Worked Nitinol, Grant R. Caraway, Samuel J. Canovas
Materials Engineering
To characterize the decrease in ductility caused by an induced stress concentration as a function of various levels of cold work and heat treatment, Nitinol medical guide wires with a .004″ diameter were tested using both a standard, straight tensile test and a modified, bent tensile test. The ratio of the two break loads (bent:straight) for identically processed samples was used as a proxy for measuring the ductility of the guide wires: the higher the ratio, the more ductile the sample. The average break load ratio as a function of increased cold work, decreased from 1.27 to 0.91 for the …
Characterization Of The 15-5 Stainless Steel Electric Discharge Machining Recast Layer, Julian R. Lohser, Rhys W. Gilmore
Characterization Of The 15-5 Stainless Steel Electric Discharge Machining Recast Layer, Julian R. Lohser, Rhys W. Gilmore
Materials Engineering
Electric discharge machining (EDM) is a non-conventional machining process that is used for tough, hard materials or materials that require no tool force. Wire EDM produces a recast layer and heat-affected zone as a result of rapid melting and quenching at the surface of the cut. A secondary machining operation has been required to remove this layer. Previous estimates of the depth of the recast layer are likely too conservative due to improvements in the technology; therefore, the goal of this study is to characterize and more accurately investigate the size of the layer. Two EDM machine parameters, voltage and …
Predicting Service Life Of 347 Stainless Steel Pipes By Carburization Rate Measurement, Tyler L. Sura
Predicting Service Life Of 347 Stainless Steel Pipes By Carburization Rate Measurement, Tyler L. Sura
Materials Engineering
Chevron Corporation and other refiners face challenges predicting the service life of piping in coker furnaces. This is largely due to a build up coke on a single surface of the piping. This coke build up results in carbon penetration into the surface of the 347 stainless steel used for the pipes. Carbon penetration can lead to degradation of the surface and ultimately, the failure of the pipe. Current modeling software has difficulty predicting the influence of sulfur on the carbon penetration rate. This study aims to provide a baseline for further study into the subject. The carbon penetration rate …
Development Of Low Cost Braze Alloys For Aerospace Applications, Alyssa M. Elliott, Sandy Babich, Blake Whitmee
Development Of Low Cost Braze Alloys For Aerospace Applications, Alyssa M. Elliott, Sandy Babich, Blake Whitmee
Materials Engineering
Non-precious metal braze alloys can help lower the cost of brazing, which is a commonly-used joining process in the aerospace industry. A-286, a stainless steel superalloy, and Inconel© 718, a nickel-based superalloy, are both commonly used alloys at Aerojet Rocketdyne. Both alloys were brazed into butt joints using nickel-based braze alloys: AMS 4776, 4777, and 4778. The brazed samples were machined into a modified version of the ASTM E8 subsize specimen samples and tensile tested to compare the strength and calculated elongation of the brazed samples to the base metals’ properties. All of the brazed samples fractured at the joint, …
Comparison Study Of Tensile Strength , Ductility, And Fracture Mode Of H11, Arp 2000, And Mp35n Connecting Rod Bolts For Use In High Performance Racing Engines, Megan Mccabe, Samuel Randall
Comparison Study Of Tensile Strength , Ductility, And Fracture Mode Of H11, Arp 2000, And Mp35n Connecting Rod Bolts For Use In High Performance Racing Engines, Megan Mccabe, Samuel Randall
Materials Engineering
Oliver Racing Parts (ORP) has historically purchased connecting rod bolts made of high strength, high cost, nickel-cobalt alloy, MP35N, and a medium strength, low cost, proprietary tool steel called ARP 2000. ORP has recently acquired capabilities to manufacture their own bolts. To determine the quality of their product as it compares to their previous supplier, ORP produced three different types of ⅜” diameter bolts: one set of bolts made of MP35N, and two sets of H11 bolts, designated H11A and H11B for their respective processing. The H11, ARP 2000, and MP35N bolts were tensile tested using a custom designed test …
Effect Of Thermal Exposure On Tensile Strength And Microhardness Of Welded And Precipitation Hardened Rx82 Aluminum Alloy Extrusions In The T4 And T6 Conditions, Lucien Miller
Materials Engineering
This investigation is focused on the effect paint-bake cycles have on the tensile strength and microhardness of GMAW welded RX82 aluminum extrusions in T4 and T6 base conditions. To simulate the paint-bake cycle, T4 and T6 RX82 aluminum samples were GMAW welded and heat treated at 350°F, 390°F, and 425°F for durations of 30 minutes, 1.0 hour, and 2.0 hours, with five replicates for each treatment. Microhardness profiles of T4 samples treated at 350°F for 30 minutes and 1.0 hour display weld/HAZ HV values of 86.04 and 82.51 respectively, followed by maximums of 123.21 and 121.10. Average ultimate tensile strength …
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 …
Welding Procedure Qualification Of A36 Steel Plates Using The Gtaw And Gmaw Processes, Brecken Deoilers, Neri Lupian, Regan Rumph
Welding Procedure Qualification Of A36 Steel Plates Using The Gtaw And Gmaw Processes, Brecken Deoilers, Neri Lupian, Regan Rumph
Materials Engineering
The purpose of this project was to qualify welding procedure specifications for the Las Positas College welding program using A36 steel in accordance with American Welding Society (AWS) D1.1, B4.0, and B2.1. Qualification was to be performed using both 1G (flat) and 3G (vertical) positions for Gas Tungsten Arc Welding (GTAW) and Gas Metal Arc Welding (GMAW) processes. Required qualification procedures included two face and two root bend tests coupled with a visual inspection for cracks within the weld region greater than ⅛” long, along with two reduced section tensile tests to ensure the tensile strength exceeded 58 ksi if …
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 …
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 …
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 …
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 …
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 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 …
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 …
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 …
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 …
The Effects Of Austempering And Cryogenic Processing On The Mechanical Properties Of Forged E4340 Steel For Automotive Engine Connecting Rods, Aaron Taylor Ludlow
The Effects Of Austempering And Cryogenic Processing On The Mechanical Properties Of Forged E4340 Steel For Automotive Engine Connecting Rods, Aaron Taylor Ludlow
Materials Engineering
The components in top-fuel dragster and stock car engines undergo significantly more force than their production passenger vehicle counterparts do. Therefore, they must be manufactured and processed to withstand those forces so that they do not catastrophically fail while in service. In this project, the effects of austempering and adding a cryogenic processing step to the control quench and double temper heat treatment on the tensile and hardness properties of E4340 high-strength steel were examined. Tensile test samples were machined from raw connecting rod forgings and underwent either a quench-double temper heat treatment, an austempering heat treatment, or the quench-double …
The Effect Of Silicon On The Electrochemical Corrosion Resistance Of Carbon Steel, Loan Faget, Michael S. Rouse
The Effect Of Silicon On The Electrochemical Corrosion Resistance Of Carbon Steel, Loan Faget, Michael S. Rouse
Materials Engineering
The purpose of this study was to investigate how the silicon (Si) content of carbon steels affects their electrochemical corrosion resistance. Tests were conducted using concentrated HCl and carbonated water on three carbon steels with different levels of silicon: 0.02, 0,19, and 0.94 weight percent. Like H2S, the prime concern of Chevron, HCl and CO2 are corrosive components in oil refinery. Electrochemical properties were measured using a potentiodynamic test outlined in Standard ASTM G59-97: Test Method for Conducting Potentiodynamic Polarization Resistance Measurements. Previous studies have determined that adding silicon to steel increases the corrosion resistance; however, results show that corrosion …
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 …
An Intercritical Heat Treatment Study Of High Strength, Microalloyed Ferrous Open Die Forgings, Kelly Elizabeth Stewart
An Intercritical Heat Treatment Study Of High Strength, Microalloyed Ferrous Open Die Forgings, Kelly Elizabeth Stewart
Materials Engineering
High strength, low alloy steel is most commonly utilized in plate or sheet form-with a thickness under 4 in, one unconventional application however, is open die forging where cross-sectional area can be as large as 9.5 in by 11.5 in. When forging to larger section size than one would thermo-mechanically roll sheet steel, a new set of complications, such as variation in microstructure and mechanical properties, arise. This study investigates the heat treatment and processing options needed to negate the inherent microstructural irregularity and Charpy V-Notch (CVN) toughness variation. Intercritical heat treatment—normalizing and then quench and tempering above the A …
High Cycle Rotating Bending Fatigue Of 6061-T6 Friction Stir Welded Extrusions, John Chang, Travis Miller
High Cycle Rotating Bending Fatigue Of 6061-T6 Friction Stir Welded Extrusions, John Chang, Travis Miller
Materials Engineering
Fatigue testing was done on friction stir welded joints of 6061-T6 aluminum extrusions. Tests were run using a rotating bending fatigue machine at stresses from 111.5 to 138.7 MPa. Failures occurred on the order of 105 to 107 cycles, and an S-N curve was generated based off of the failure results. After the samples failed, the location of the failure and the number of cycles to failure were noted. Fatigue samples were designed in SolidWorks with a tapered 2 inch reduced section. The 2 inch reduced section will include the entire weld region as seen from the microhardness …
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 …
Relationship Between Bagging Methods And Pre-Weld Holding Times On Porosity Formation In 2219 Aluminum Ac-Tig Welds, Mariah Grace Head, Tyson Daniel Mobley
Relationship Between Bagging Methods And Pre-Weld Holding Times On Porosity Formation In 2219 Aluminum Ac-Tig Welds, Mariah Grace Head, Tyson Daniel Mobley
Materials Engineering
The purpose of this study was to determine relationships between bagging methods and pre-weld holding times on the formation of porosity when AC-TIG welding 2219 aluminum. Considering the strict guidelines and specifications required within the aerospace industry, maintaining quality welds is of paramount importance to control part integrity for aerospace applications. This project focused on two parameters involved in the preparation of aluminum parts for welding: bagging method and pre-weld holding time. Welding geometry was simplified to bead-on plate instead of the standard joint welds. Radiographic analysis of the samples showed that all levels of both parameters produced “passing welds.” …