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Articles 1 - 19 of 19
Full-Text Articles in Engineering
Investigation Into Oxygen Diffusion As It Relates To Alpha Case Formation In Ti-6al-4v Based On Different Forging Thermal Cycles, Tyler J. Meador, Jon Leduc, Francesca Hope
Investigation Into Oxygen Diffusion As It Relates To Alpha Case Formation In Ti-6al-4v Based On Different Forging Thermal Cycles, Tyler J. Meador, Jon Leduc, Francesca Hope
Materials Engineering
An investigation into the growth kinetics of alpha case in Ti-6Al-4V in the presence of oxygen was conducted for different forging thermal cycles. This was done to determine whether the alpha case should be removed after each thermal cycle or as the final step after forging. The thermal cycles consisted of four hours at 1750 °F. Samples were subjected to this treatment one, two, three, and four times along with a continuous sixteen hour hold. Four cycle and Hold samples were subjected to an additional thermal cycle above the beta transus at 1925 °F. These then went through a final …
Strengthening Of 7175 Aluminum Alloy Through Multi-Step Aging Process, Colin E. Masterson, Ryland W. Jolliffe
Strengthening Of 7175 Aluminum Alloy Through Multi-Step Aging Process, Colin E. Masterson, Ryland W. Jolliffe
Materials Engineering
7175 is a heat-treatable aluminum alloy commonly used in aerospace forgings. This alloy is aged with a multi-step heat treatment. This treatment must balance strength with stress corrosion cracking resistance through a degree of overaging. The team was tasked by Weber Metals to increase the strength of this treatment without sacrificing stress corrosion cracking resistance. Both two-step and retrogression and reaging treatments were tested in experiments to find a heat treatment that could increase the yield and tensile strength by 1-2 ksi while maintaining a minimum electrochemical conductivity equivalence of 38% relative to copper. Two-step aging is the more conventional …
Process-Structure-Property Relationship In Magnesium-Based Biodegradable Alloy For Biomedical Applications, Pramanshu Trivedi
Process-Structure-Property Relationship In Magnesium-Based Biodegradable Alloy For Biomedical Applications, Pramanshu Trivedi
Open Access Theses & Dissertations
Magnesium alloys are considered to be the next generation of biomaterials because of their ability to degrade in the physiological environment. We elucidate here the impact of multiaxial forging of Mg-2Zn-2Gd alloy on grain refinement to sub-micron regime and relate the structure to mechanical properties and biological functionality. As-cast and annealed samples were multiaxial forged (MAF) for a total number of two passes with a true strain of ~2/pass. Considering that the microstructure governs the biological response of materials, we studied the constituents of the microstructure in conjunction with the mechanical behavior. The antimicrobial behavior in a Mg-2Zn-2Gd alloy with …
Characterization Of Thermal Deformation Behavior Of A Novel Tial Alloy, Xiaopeng Wang, Fantao Kong, Qin Su, Yu Zhang, Yuyong Chen
Characterization Of Thermal Deformation Behavior Of A Novel Tial Alloy, Xiaopeng Wang, Fantao Kong, Qin Su, Yu Zhang, Yuyong Chen
The 8th International Conference on Physical and Numerical Simulation of Materials Processing
No abstract provided.
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 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 …
Effect Of Carbon On Primary Alpha Percentage In Ti-6al-4v As Temperature Approaches The Beta Transus, Kyle Savage
Effect Of Carbon On Primary Alpha Percentage In Ti-6al-4v As Temperature Approaches The Beta Transus, Kyle Savage
Materials Engineering
Some Ti-6Al-4V forgings require a specific amount of α phase known as primary α in the finished product. The percentage of primary α is dependent on how close to the beta transus temperature forging is conducted. The beta transus temperature is affected by certain alloying elements. Carbon is one of the elements known to increase the beta transus temperature. Since each Ti-6Al-4V ingot contains varying amounts of carbon, testing on a variety of chemistries needs to be conducted. Cubes approximately 0.5 inches from low, medium, and high carbon chemistries were heat treated at temperatures below the beta transus in 18 …
Evaluation Of Forging Strain For Maximum Grain Size In Open-Die Forged 6061 Aluminum, Eric Strehl
Evaluation Of Forging Strain For Maximum Grain Size In Open-Die Forged 6061 Aluminum, Eric Strehl
Materials Engineering
In an effort to maximize grain growth of open-die forged 6061 aluminum alloy parts, samples from three of Weber Metals’s suppliers (Hidal Co-Almex USA Inc., TST Inc., and Vista Metals Corp.; to be called Supplier H, Supplier T, Supplier V respectively) were cut into cylinders with diameters of 0.75˝ and heights of 2˝, and put through a simulated forging process and heat treatment. It is possible that additional alloying elements may be promoting or inhibiting grain growth in the final part. Maximizing grain growth for aluminum alloy parts results in improved resistance to intergranular corrosion. Samples from each vendor had …
Hybrid Position And Impedance Control Of A Forging Process, Derek Stake
Hybrid Position And Impedance Control Of A Forging Process, Derek Stake
ETD Archive
"Pick and place" robotic material handling has been a key to increase piece rates and reduced variability in forging processes. One of the drawbacks to current "pick and place" robotic material handling methods is the inability to locate the part after a forging operation and move it to the next position in a timely manner. If the billet changes position during the forging process, the manipulator will take longer to find the part and transfer it to the next station or the manipulator will be unable to move the part to the next position correctly which may cause scrap. Another …
Enhancing Impact Fracture Toughness And Tensile Properties Of A Microalloyed Cast Steel By Hot Forging And Post-Forging Heat Treatment Processes, Jingwei Zhao, Zhengyi Jiang, Chong Soo Lee
Enhancing Impact Fracture Toughness And Tensile Properties Of A Microalloyed Cast Steel By Hot Forging And Post-Forging Heat Treatment Processes, Jingwei Zhao, Zhengyi Jiang, Chong Soo Lee
Faculty of Engineering and Information Sciences - Papers: Part A
In the present work, the effects of hot forging and post-forging heat treatment on the impact fracture toughness and tensile properties of a microalloyed cast steel were investigated. Mechanical tests were used to evaluate the room temperature impact fracture toughness and tensile properties of the steel. The resulting microstructures were analysed by optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The extraction replica technology was used to investigate the characterisation of complex precipitates formed during heat treatment. The obtained results showed that the coarse-grained microstructure of the forged specimen was significantly refined after post-forging heat treatment. …
Effects Of Tungsten Addition And Heat Treatment Conditions On Microstructure And Mechanical Properties Of Microalloyed Forging Steels, Jingwei Zhao, Zhengyi Jiang, Chong Soo Lee
Effects Of Tungsten Addition And Heat Treatment Conditions On Microstructure And Mechanical Properties Of Microalloyed Forging Steels, Jingwei Zhao, Zhengyi Jiang, Chong Soo Lee
Faculty of Engineering and Information Sciences - Papers: Part A
In the present work, the effects of tungsten (W) addition and heat treatment conditions on the microstructure, impact toughness and tensile properties of microalloyed forging steels were studied. Four kinds of microalloyed forging steels were produced by varying W additions (0, 0.5, 1 and 2 wt%). Heat treatment was carried out at temperatures ranging from 840 to 950 °C followed by air and furnace cooling. Mechanical tests were used to evaluate the room temperature Charpy impact and tensile properties. The resulting microstructures were analysed via optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results show …
Effects Of Tungsten Addition On The Microstructure And Mechanical Properties Of Microalloyed Forging Steels, Jingwei Zhao, Taekyung Lee, Jeong Hun Lee, Zhengyi Jiang, Chong Soo Lee
Effects Of Tungsten Addition On The Microstructure And Mechanical Properties Of Microalloyed Forging Steels, Jingwei Zhao, Taekyung Lee, Jeong Hun Lee, Zhengyi Jiang, Chong Soo Lee
Faculty of Engineering and Information Sciences - Papers: Part A
In the current study, the effects of tungsten (W) addition on the microstructure, hardness, and room/low [223 K and 173 K (-50 C and -100 C)] temperature tensile properties of microalloyed forging steels were systematically investigated. Four kinds of steel specimens were produced by varying the W additions (0, 0.1, 0.5, and 1 wt pct). The microstructure showed that the addition of W does not have any noticeable effect on the amount of precipitates. The precipitates in W-containing steels were all rich in W, and the W concentration in the precipitates increased with the increasing W content. The mean sizes …
Characterization And Analysis Of Low Room Temperature Ductility Nickel-Based Superalloy 718 Plus For Aircraft Engine Forgings, Jonathon Bracci
Characterization And Analysis Of Low Room Temperature Ductility Nickel-Based Superalloy 718 Plus For Aircraft Engine Forgings, Jonathon Bracci
Materials Engineering
Schlosser Forge Co. forges low pressure turbine (LPT) cases from the nickel based superalloy 718 Plus using the ring rolling forging process. Schlosser has been experiencing low room temperature ductility problems in a number of their 718 Plus LPT cases. LPT cases are required to pass a 4D tensile test at room temperature with a minimum of 15 percent elongation. The ductility problem was reduced by increasing the forging temperature from 1825˚F to 1850˚F. Analysis was performed on 718 Plus samples taken from forged LPT cases that failed the room temperature ductility requirement and ones that passed the requirement. The …
Effect Of Heating Temperature, Heating Time And Initial Microstructure On Recrystallization Of Waspaloy During Heating For Forging, Marissa Hill
Materials Engineering
A fine, uniform grain size is required for creep limited Waspaloy in aircraft engine applications. Upon heating, Waspaloy does not always recrystallize in a uniform manner resulting in occasional large grains with a majority of the grains meeting the grain size requirements. Waspaloy’s microstructure was analyzed with different heat treatments and in the as-forged condition. The strengthening mechanism is the gamma prime phase. The gamma prime solvus temperature is 1908°F so the different heat treatments were determined around that temperature, as well as the forging temperature range of 1800-2150°F. At the 1850°F heat treatment, the microstructure recrystallized with small grains, …
Microstructural Characterization Of Ti-6al-4v And Its Relationship To Sample Geometry, Blake Gaspar
Microstructural Characterization Of Ti-6al-4v And Its Relationship To Sample Geometry, Blake Gaspar
Materials Engineering
A problem exists with a part produced by forging made by Shultz Steel of Ti-6Al-4V in the variance of properties throughout the part. There is one specific region that exhibits the most variance. The purpose of the report is to determine any microstructural differences within the region of interest in the part. When microstructures of the inner section and outer section of the part were looked at it was determined that they exhibited a martensitic structure. There was a noticeable difference in the lath structure between sections. The outer region contained larger more widely spread laths of an average length …
Analysis Of Failed Forging Saddling Mandrels And Process Improvements For Increased Mandrel Lifespan, Brock Costalupes
Analysis Of Failed Forging Saddling Mandrels And Process Improvements For Increased Mandrel Lifespan, Brock Costalupes
Materials Engineering
This project seeks to increase the lifespan of steel mandrels used by Schlosser Forge in the saddling process, which is part of the production of forged rings for the aerospace and power generation industries. All saddle mandrel samples were taken from used 4340 steel mandrels. Hardness profiles were measured across rectangular bars cut from the transverse direction of a completely fractured piece of a 7″ diameter mandrel. The hardness near one outer surface of the tested bar was 36 HRC and gradually decreased to 30.5 HRC at the opposite surface. Macroscopic examination of the primary fracture surface along with light …
Effects Of Annealing/Solution Treating And Aging On Longitudinal And Transverse Properties Of Ti-6al-4v Forgings, Blake Reller
Effects Of Annealing/Solution Treating And Aging On Longitudinal And Transverse Properties Of Ti-6al-4v Forgings, Blake Reller
Materials Engineering
Forty-eight subsize round-bar tensile samples (ASTM E8) were machined from 3-in-thick forgings of Ti-6Al-4V. Half of these samples were cut so the axis aligned with the longitudinal (LG) direction of the forging, the other half were cut to align with the transverse (LT) direction. Four samples from each direction were subjected to one of six heat treatments so that a total of eight samples received each treatment. Annealed samples were held at 1350°F for two hours, then air cooled. Solution treated and aged (STA) samples were solution treated at one of five temperatures between 1785°F and 1435°F for one hour …
Characterization Of Positive Macrosegregation At The Subsurface Of Direct-Chill Cast 7050 Aluminum Forging Billets, Aaron Youril
Characterization Of Positive Macrosegregation At The Subsurface Of Direct-Chill Cast 7050 Aluminum Forging Billets, Aaron Youril
Materials Engineering
Segregation of alloying elements during casting of forging billets may persist to the final forged component leading to unacceptable surface appearance. Determination of the elements or compounds that segregate is the essential first step to solving this problem. Differential Scanning Calorimetry (DSC) was used to determine a composition profile of the macrosegregation occurring at the subsurface of an as-cast 7050 aluminum alloy billet. Data collection was carried out by separating 10 to 20 mg samples from the outer centimeter along the radius of the billet, as well as samples from the bulk interior of the billet for comparison with the …
Effect Of The Sinter-Forging Deformation Rate On Properties Of Bi-2223 Current Leads, X. K. Fu, Y. C. Guo, W. M. Chen, Hua-Kun Liu, S. X. Dou
Effect Of The Sinter-Forging Deformation Rate On Properties Of Bi-2223 Current Leads, X. K. Fu, Y. C. Guo, W. M. Chen, Hua-Kun Liu, S. X. Dou
Faculty of Engineering - Papers (Archive)
The influence of the sinter-forging rate on the critical current density (Jc) behaviour in an external field and on the contact resistance Rc for Bi-2223 current leads has been investigated. The current leads were fabricated by a combination of cold isostatic pressing (CIP) and sinter-forging methods with the thickness reduction rate ranging from 0% to 90%. The two silver contact terminals of each sample were also prepared during the sinter-forging. The results revealed that Jc was strongly affected by the deformation rate of sinter-forging and reached a maximum of 725 A/cm2 at a deformation rate of 80%. From the measurements …