Manufacturing Commons^™

Material Extrusion 3d Printing Of Metal Alloy: Material, Methods And Application., Sihan Zhang

Electronic Theses and Dissertations

Material extrusion (MEX) additive manufacturing presents a promising pathway for producing metal components with complex geometries while avoiding the safety hazards associated with loose powder handling in conventional metal additive manufacturing processes. This dissertation investigates the development and optimization of MEX processes for aluminum alloys, addressing critical challenges in feedstock formulation, printing parameter optimization, and post-processing strategies. Three distinct approaches were explored to advance the capabilities of aluminum MEX: filament-based processing of 6061 aluminum, paste-based extrusion of 6061 aluminum, and development of a novel aluminum-magnesium-tin alloy system for space manufacturing applications. The filament-based approach successfully demonstrated the production of 6061 …

Experimental Characterisation Of Laser Cladding Of Crniw And Crnifealzr Powders On H13 Tool Steel And Optimisation Of Process Parameters, Martin Vinoth S

Theses and Dissertations

In this work, laser cladding on H13 steel substrate with two different powder compositions CrNiW and CrNiFeAlZr has been carried out. The laser power, powder feed rate, and scanning speed were varied and the clad dimensions, aspect ratio, and dilution percentage were measured. The microhardness found in the CrNiW clad is 834 ± 20 HV0.5, which is higher than that of the CrNiFeAlZr clad (780 ± 20 HV0.5) as well as the substrate (548 ± 20 HV0.5).

The X-ray Diffraction (XRD) patterns identified the common phase creation of Ni3C and Fe3C for CrNiFeAlZr and CrNiW coatings, while the oxide formation …

A Comprehensive Study Of Cooling Rate Effects On Diffusion, Microstructural Evolution, And Characterization Of Aluminum Alloys, Atiqur Rahman, Sriram Praneeth Isanaka, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Cooling Rate (CR) definitively influences the microstructure of metallic parts manufactured through various processes. Factors including cooling medium, surface area, thermal conductivity, and temperature control can influence both predicted and unforeseen impacts that then influence the results of mechanical properties. This comprehensive study explores the impact of CRs in diffusion, microstructural development, and the characterization of aluminum alloys and the influence of various manufacturing processes and post-process treatments, and it studies analytical models that can predict their effects. It examines a broad range of CRs encountered in diverse manufacturing methods, such as laser powder bed fusion (LPBF), directed energy deposition …

Effect Of Alloying Additions On Austenite Refinement In Nickel-Alloyed Ductile Cast Irons, Adnan Adib Aahamed

College of Graduate Studies: Theses & Dissertations

The benefits associated with the application of ductile irons are significantly attributed to the control of microstructures, with refinement of austenitic matrix during solidification playing a significant role. Nickel alloyed ductile irons are attractive due to their potential for high ductility and suitability for potential high-temperature applications with stable austenitic microstructure. Refinement of austenite grain structure is thus important to enhance the mechanical properties of the alloyed ductile iron. This research investigates the impact of in-mold additions of different alloying elements on the austenite morphology and grain refinement of nickel-alloyed ductile iron along with the associated mechanical properties. A hypoeutectic …

Synergistic Strategies In Sinter-Based Material Extrusion (Mex) 3d Printing Of Copper: Process Development, Product Design, Predictive Maps And Models., Kameswara Pavan Kumar Ajjarapu

Electronic Theses and Dissertations

3D printing pure copper with high electrical conductivity and exceptional density has long been challenging. While laser-based additive manufacturing technologies suffered due to copper's highly reflective nature towards laser beams, parts printed via binder-assisted technologies failed to reach over 90% IACS (International Annealed Copper Standard), electrical conductivity. Although promising techniques such as binder jetting, filament, and pellet-based 3D printing that can print copper exist, they however still face difficulties in achieving both high sintered densities and electrical conductivity values. This is due to a lack of comprehensive understanding of property evolution from green to sintered states and the strategies that …

A High-Strength Precipitation Hardened Cobalt-Free High-Entropy Alloy, Matthew Luebbe, Jiaqi Duan, Fan Zhang, Jonathan Poplawsky, Hans Pommeranke, Maalavan Arivu, Andrew Hoffman, Mario Buchely, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Recent studies on precipitation-hardened high-entropy alloys (HEAs) demonstrate their high strength and thermal stability, making them promising materials for high-temperature structural applications such as nuclear reactors. However, many existing HEAs contain cobalt (Co), which is unsuitable for nuclear applications because of the long-term activation issue of Co. Co is also expensive and considered a critical material for other applications. Therefore, it is desired to exclude Co from the composition. a Co-free (Fe0.3Ni0.3Mn0.3Cr0.1)88Ti4Al8 HEA was developed and studied in this work. in contrast to previous Co-free HEAs, this alloy is close to Equi atomic in its composition and promises a more …

Material Property Dependence Of Nanoparticle Silicon Carbide Alloying In Additively Manufactured Molybdenum, Andrew P. Mason

Theses and Dissertations

The structural performance of additively manufactured Mo printed by LPBF can be significantly improved by nanoparticle alloying. Previous AFIT studies of SiC nanoparticle addition conducted by Ellsworth (2022) et al. demonstrated increased powder consolidation, leading to reduced porosity, increased microhardness, and a shift in atomic defect concentrations. The addition of defected SiC particles is proposed to reduce in situ oxidation by acting as a sacrificial oxidizing agent and contributing to the formation of Mo disilicide secondary phases. This study investigated the relationship between laser powder bed fusion Mo microscale and nanoscale properties with varying SiC particle size while maintaining a …

Evaluation Of Microstructural And Mechanical Behavior Of Ahss Cp780 Steel Welded By Gmaw-Pulsed And Gmaw-Pulsed-Brazing Processes, Alan Jadir Romero-Orozco, Jaime Taha-Tijerina, Rene De Luna-Alanis, Victor Hugo Lopez-Morelos, Maria Del Carmen Ramirez, Melchor Salazar-Martinez, Francisco Fernando Curiel-Lopez

Manufacturing & Industrial Engineering Faculty Publications

Joints of complex phase 780 (CP-780) advanced high strength steel (AHSS) were carried out by using an ER-CuAl-A2 filler metal for the gas metal arc welding pulsed brazing (GMAW-P- brazing) process and the ER-80S-D2 for the GMAW-P process employing two levels of heat input. The phases in the weld bead and HAZ were analyzed, and the evaporation of zinc by means of scanning electron microscopy (SEM) was also monitored. The mechanical properties of the welded joints were evaluated by tension, microhardness and vertical impact tests. It was found that there was greater surface Zn evaporation in the joints welded with …

Investigation Of Different Hatch Strategies On High Entropy Alloy Fabrication By Selective Laser Melting, Joni Chandra Dhar

Theses and Dissertations

This study investigated the synthesis of CuCrFeNiTiAl high entropy alloy (HEA) from pure elements using selective laser melting (SLM). The objectives are to validate the feasibility of the HEA fabrication from elemental powder materials, and to examine the effect of various hatch strategies and energy densities on the microstructures and other materials properties. 3D samples of CuCrFeNiTiAl alloy were fabricated under different energy densities and with different scan vector lengths. The as-built samples were characterized by X-ray diffraction (XRD), and the microstructures were observed using scanning electron microscopy (SEM). The XRD results showed that face centered cubic, and body centered …

Direct Selective Laser Synthesis Of Cucrfenitial High Entropy Alloy From Elemental Powders Through Selective Laser Melting, Joni Dhar, Lazaro Lopez, Shanshan Zhang, Ben Xu, Mohammed Jasim Uddin, Jianzhi Li

Manufacturing & Industrial Engineering Faculty Publications

This study investigated the synthesis of CuCrFeNiTiAl high entropy alloy (HEA) from pure elements using selective laser melting (SLM). The objectives are to validate the feasibility of the HEA fabrication from elemental powder materials, and to examine the effect of various process conditions in SLM, such as laser power, point distance and laser exposure time, on the microstructures formed. The as-built samples under high, medium and low energy densities were characterized by X-ray diffraction (XRD), and the microstructures were observed using scanning electron microscopy (SEM). The XRD results showed that five major crystal structure phases (hexagonal, monoclinic, orthorhombic, body-centered cubic …

Materials-Processing Relationships For Metal Fused Filament Fabrication Of Ti-6al-4v Alloy., Paramjot Singh

Electronic Theses and Dissertations

Additive manufacturing (AM) is at the mainstream to cater the needs for rapid tooling and small-scale part production. The metal AM of complex geometries is widely accepted and promoted in the industry. While several metal AM technologies exist and are matured to a level where expectation in terms of design and properties are possible to realize. But the metal AM suffers from the heavy expense to acquire equipment, isotropic property challenges, and potential hazards to work with loose reactive metal powder. With this motivation, the dissertation aims to develop the fundamental aspects to print metal parts with bound Ti-6Al-4V powder …

A Study On Ultrasonic Energy Assisted Metal Processing : Its Correeltion With Microstructure And Properties, And Its Application To Additive Manufacturing., Anagh Deshpande

Electronic Theses and Dissertations

Additive manufacturing or 3d printing is the process of constructing a 3-dimensional object layer-by-layer. This additive approach to manufacturing has enabled fabrication of complex components directly from a computer model (or a CAD model). The process has now matured from its earlier version of being a rapid prototyping tool to a technology that can fabricate service-ready components. Development of low-cost polymer additive manufacturing printers enabled by open source Fused Deposition Modeling (FDM) printers and printers of other technologies like SLA and binder jetting has made polymer additive manufacturing accessible and affordable. But the metal additive manufacturing technologies are still expensive …

Process-Property-Microstructure Relationships In Laser-Powder Bed Fusion Of 420 Stainless Steel., Subrata Deb Nath

Electronic Theses and Dissertations

Laser-powder bed fusion (L-PBF) is an additive manufacturing technique for fabricating metal components with complex design and customized features. However, only a limited number of materials have been widely studied using L-PBF. AISI 420 stainless steel, an alloy with a useful combination of high strength, hardness, and corrosion resistance, is an example of one such material where few L-PBF investigations have emerged to date. In this dissertation, L-PBF experiments were conducted using 420 stainless steel powders to understand the effects of chemical composition, particle size distribution and processing parameters on ensuing physical, mechanical and corrosion properties and microstructure in comparison …

Shape Memory Behavior Of Dense And Porous Niti Alloys Fabricated By Selective Laser Melting, Soheil Saedi

Theses and Dissertations--Mechanical and Aerospace Engineering

Selective Laser Melting (SLM) of Additive Manufacturing is an attractive fabrication method that employs CAD data to selectively melt the metal powder layer by layer via a laser beam and produce a 3D part. This method not only opens a new window in overcoming traditional NiTi fabrication problems but also for producing porous or complex shaped structures. The combination of SLM fabrication advantages with the unique properties of NiTi alloys, such as shape memory effect, superelasticity, high ductility, work output, corrosion, biocompatibility, etc. makes SLM NiTi alloys extremely promising for numerous applications.

The SLM process parameters such as laser power, …

Simulation Of Two Kinds Of Hot Stamping Processes Of Ultra High-Strength Steel, Hao Zhao, Zhongwen Xing, Hongliang Yang

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Weld Thermal Simulation Of Crmov With Pwht In Type Iv Region, Bin Xu

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Flow Stress And Microstructure Models Of Alloys, Lars-Erik Lindgren

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Cryogenic Processing Of Al 7050-T7451 Alloy For Improved Surface Integrity, Bo Huang

Theses and Dissertations--Mechanical and Aerospace Engineering

Al 7050-T7451 alloy with good combinations of strength, stress corrosion cracking resistance and toughness, is used broadly in the aerospace/aviation industry for fatigue-critical airframe structural components. However, it is also considered as a highly anisotropic alloy as the crack growth behavior along the short transverse direction is very different from the one in the long transverse direction, due to the inhomogeneous microstructure with the elongated grains distributed in the work material used in the sheet/plate applications. Further processes on these materials are needed to improve its mechanical and material properties and broaden its applications.

The material with ultra-fine or nano …

Probabilistic Simulation Of Solidification Microstructure Evolution During Laser-Based Metal Deposition, Jingwei Zhang, Frank W. Liou, William Seufzer, Joseph William Newkirk, Zhiqiang Fan, Heng Liu, Todd E. Sparks

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A predictive model, based on a Cellular Automaton (CA) - Finite Element (FE) method, has been developed to simulate microstructure evolution during metal solidification for a laser based additive manufacturing process. The macroscopic FE calculation was designed to update the temperature field and simulate a high cooling rate. In the microscopic CA model, heterogeneous nucleation sites, preferential growth orientation and dendritic grain growth kinetics were simulated. The CA model was able to show the entrapment of neighboring cells and the relationship between undercooling and the grain growth rate. The model predicted the dendritic grain size, structure, and morphological evolution during …

Evaluation Of Mechanical Properties And Microstructure For Laser Deposition Process And Welding Process, Yaxin Bao, Jianzhong Ruan, Todd E. Sparks, Jambunathan Anand, Joseph William Newkirk, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Laser Aided Manufacturing Process (LAMP) can be applied to repair steel die/molds which are currently repaired using traditional welding process in industry. In order to fully understand the advantages of laser deposition repair process over traditional welded-repair process, the mechanical properties such as tensile strength and hardness of H13 tool steel samples produced by these two processes were investigated. The microstructure and fracture surface of the samples were analyzed using optical microscope and SEM (Scanning Electron Microscope). Moreover, depositions on substrates with different shapes were studied to evaluate the performance of LAMP on damaged parts with complicated geometric shape.