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Title: Towards Understanding the Microstructure and Mechanical Properties of Additively Manufactured Ni-base Superalloys
Creator: Tiparti, Dhruv Reddy
Date: 2022
Description: Nickel-base superalloy components such as turbine discs typically undergo numerous manufacturing steps that contribute to increasing the cost...
Show moreNickel-base superalloy components such as turbine discs typically undergo numerous manufacturing steps that contribute to increasing the cost and the waste of excess materials. With advent of fusion based additive of manufacturing (AM) techniques, such components with complex geometry can be fabricated with great efficiency. However due to characteristically high energy densities, fast cooling rate, and layer-by-layer building process associated with AM; Ni-base superalloys with higher temperature performance are difficult to be fabricated by AM due to susceptibility to composition related defect formation, which is further exacerbated by anisotropic grain structures induced by the large thermal gradients present. Crack-free material can be fabricated but, in most cases, issues such as an anisotropic microstructure will prevail, and the balance of mechanical properties achieved may not be suitable for the desired applications. Several strategies exist to mitigate the challenges posed by additive manufacturing via post-processing such as hot-isostatic processing, annealing heat treatments, application of grain refining inoculants, etc. All these strategies utilized to mitigate issues with AM of Ni-base superalloys still require further study to understand their effects on the microstructure and mechanical properties. This work aims to evaluate the use of inoculant particles, and novel heat treatments on the microstructure and mechanical properties of different superalloys. First, the effect of varying amounts of CoAl2O4 inoculant ranging from 0 to 2 wt.% on the microstructure evolution of Inconel 718(IN718) fabricated by selective laser melting (SLM) was evaluated. The findings from this study indicated that additions of CoAl2O4 only resulted in a minor degree of grain refinement with slight increase in anisotropy; in addition, a CoAl2O4 ¬content above 0.2 wt.% resulted in the formation of agglomerate inclusions; and that to effectively utilize CoAl2O4 as a grain refining inoculant, process parameters must be further optimized while considering the formation of agglomerates, and other defects. Second, the application of CoAl2¬O4 was extended towards the Direct Energy Deposition (DED) of IN718. Here findings indicated that due to the modification of the thermophysical properties of the melt pool by oxide addition, an earlier onset of large columnar extending across multiple layers occurred while counteracting conditions required for equiaxed grain formation; and these CoAl2O4 were also found to exhibit a potent Zenner pinning effect that maintained the as-built grain structure despite application of extreme high treatment condition of 1200oC for 4 hrs. Third, the tensile and fatigue properties of the DED IN718 with CoAl2O4 were evaluated. Here, it was found that the addition of CoAl2O4 leads to a minor increase in tensile strength in the as-built condition attributed primarily to the fine oxide dispersion; a more modest increase in tensile strength in the heat-treated condition due to grain refinement induced by retaining the as-built grain structure; and that despite the increase in tensile strength with CoAl2O4 a corresponding increase in fatigue life did not occur. Lastly, the processing of René 65 conducted by laser-powder bed fusion(L-PBF) was done and compared to the conventionally cast and wrought material. Here, the effect of the difference in processing route in conjunction with heat treatments was evaluated to understand the creep and stress relaxation behavior. It was found that L-PBF of René 65 led to an overall improved resistance to deformation by creep and relaxation mechanism.
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Title: SYNTHESIS AND CHARACTERIZATION OF MG, NB, TI-DOPED LINIO2 CATHODE MATERIAL FOR LI-ION BATTERIES
Creator: Tian, Yiwen
Date: 2022
Description: In this project, the influence of several metal doping on the electrochemical properties of LiNiO2 materials was analyzed. The doping method...
Show moreIn this project, the influence of several metal doping on the electrochemical properties of LiNiO2 materials was analyzed. The doping method is aiming to improve the stability of the layered structure and inhibit the mixing of nickel and lithium by enhancing the structural stability of the layered material and replacing part of Ni with other metals in the process of intercalation/deintercalation, thereby promoting the cyclic performance and reversible capacity. The LiNiO2 powder doped with Nb, Ti and Mg is denoted as Li0.96Ni0.9Nb0.06Ti0.04Mg0.02O2 or, in short, metal-doped LiNiO2. The synthesis of the metal-doped LiNiO2 powder consists of mixing the lithium and nickel sources with various metal oxides and then being subjected to high-energy ball milling for 10 hours, followed by heating for 20 h in a metallic tube furnace at 680℃ with flowing oxygen atmosphere. The undoped LiNiO2 powder synthesized using the same process and conditions was compared with the doped LiNiO2 powder. In order to understand the doping mechanism, field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD) were used to analyze the morphology, composition and crystal structure of the final product. Benefiting from the Mg, Nb, and Ti doping, the doped LiNiO2 exhibited a high reversible capacity of 130.56 mAh g-1, higher than that of undoped LiNiO2 (95.02 mAh g-1) under the 0.1C charge/discharge rate in the voltage window between 2.5 and 4.2 V. Further, the doped LiNiO2 has 86% of capacity retention over 100 cycles, better than undoped LiNiO2 (only 44% of capacity retention) under the 0.5C charge/discharge rate between 2.5 and 4.2 V.
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Title: Quality of Life in People with Epilepsy: The Associations of Anti-seizure Medications and Biopsychosocial Variables
Creator: Thomas, Julia A.
Date: 2022
Description: People with epilepsy, on average, experience lower quality of life (QOL) than healthy controls (Taylor et al., 2011). This study examined the...
Show morePeople with epilepsy, on average, experience lower quality of life (QOL) than healthy controls (Taylor et al., 2011). This study examined the associations between specific anti-seizure medication, biopsychosocial factors, and QOL in people with epilepsy. Analysis of covariance revealed that individuals taking three or more anti-seizure medications had significantly lower QOL than those taking levetiracetam. Findings also demonstrated that when looking at biopsychosocial factors as predictors of QOL in hierarchical regression, anxiety, depression, and daytime sleepiness were significant predictors of QOL. Once these factors were entered into the model, number of medications was no longer significant. The final model predicted 59.6% of the variance in QOL. Lastly, a moderation analysis to examine the moderating effect of employment on the association between number of anti-seizure medications and QOL was not significant. Additional exploratory analyses looking at individuals who were employed versus those who were not employed were completed. These findings underscore the importance of addressing psychological health and sleep factors within the epilepsy population.
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Title: Child and Family Outcomes Associated with Specific Maryland ASD Waiver Services and Choice and Control as Mediators of These Outcomes
Creator: Turchmanovych-Hienkel, Nataliya
Date: 2022
Description: Autism spectrum disorder (ASD) is a neurodevelopmental condition that affects 1in 44 children and is characterized by impairments in cognitive...
Show moreAutism spectrum disorder (ASD) is a neurodevelopmental condition that affects 1in 44 children and is characterized by impairments in cognitive, behavioral, and social domains of functioning. Literature suggests that ASD not only impacts the quality of life of the individuals diagnosed with this condition, but also has a negative impact on family quality of life (FQoL). Interventions and services offered through the Medicaid 1915(c) Home and Community-Based Services waiver programs can enhance child and family outcomes. The present study looked at one specific waiver program, the Maryland ASD waiver, and examined the frequency at which families received different waiver services and the associations between those service frequencies and child (i.e., academic performance, independent living skills, social communication and interaction skills, stereotypic and repetitive behavior, and aggressive behavior) and family (i.e., FQoL) outcomes, as well as explored whether the family’s perception of choice and control mediate these child and family outcomes. Results suggest that frequencies of some waiver services are associated with progress in some child outcomes, but not in FQoL. This study also suggests that the choice and control that families have over services do not mediate the relation between frequency of waiver services and child and family outcomes. Overall, results suggest that the Maryland ASD waiver program may help improve some domains of child functioning.
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Title: Choice-Distinguishing Colorings of Cartesian Products of Graphs
Creator: Tomlins, Christian James
Date: 2022
Description: A coloring $f: V(G)\rightarrow \mathbb N$ of a graph $G$ is said to be \emph{distinguishing} if no non-identity automorphism preserves every...
Show moreA coloring $f: V(G)\rightarrow \mathbb N$ of a graph $G$ is said to be \emph{distinguishing} if no non-identity automorphism preserves every vertex color. The distinguishing number, $D(G)$, of a graph $G$ is the smallest positive integer $k$ such that there exists a distinguishing coloring $f: V(G)\rightarrow [k]$ and was introduced by Albertson and Collins in their paper ``Symmetry Breaking in Graphs.'' By restricting what kinds of colorings are considered, many variations of distinguishing numbers have been studied. In this paper, we study proper list-colorings of graphs which are also distinguishing and investigate the choice-distinguishing number $\text{ch}_D(G)$ of a graph $G$. Primarily, we focus on the choice-distinguishing number of Cartesian products of graphs. We determine the exact value of $\text{ch}_D(G)$ for lattice graphs and prism graphs and provide an upper bound on the choice-distinguishing number of the Cartesian products of two relatively prime graphs, assuming a sufficient condition is satisfied. We use this result to bound the choice distinguishing number of toroidal grids and the Cartesian product of a tree with a clique. We conclude with a discussion on how, depending on the graphs $G$ and $H$, we may weaken the sufficient condition needed to bound $\text{ch}_D(G\square H)$.
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Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1964
Creator: Brandt & Associates
Date: 1964
Description: Aerial photograph of the Illinois Institute of Technology campus, looking northeast.
Collection: IIT Campus Aerial photographs, 1940-2002

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1958
Creator: Brandt & Associates
Date: 1958
Description: Aerial photograph of the Illinois Institute of Technology campus, looking southwest.
Collection: IIT Campus Aerial photographs, 1940-2002

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1963
Creator: Brandt & Associates
Date: 1963
Description: Aerial photograph of the Illinois Institute of Technology campus, looking north.
Collection: IIT Campus Aerial photographs, 1940-2002

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1950
Date: 1950
Description: Aerial photograph of the Illinois Institute of Technology campus, looking southwest. Photographer unknown.
Collection: IIT Campus Aerial photographs, 1940-2002

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1940
Date: 1940
Description: Aerial photograph of the Illinois Institute of Technology campus, looking north. Photographer unknown.
Collection: IIT Campus Aerial photographs, 1940-2002

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1975
Creator: Brandt & Associates, Ltd.
Date: 1975
Description: Aerial photograph of Mies Campus, looking north.
Collection: IIT Campus Aerial photographs, 1940-2002

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1985
Date: 1985-10-24
Description: Aerial photograph of Mies Campus, looking north, 1985. Photographer unknown.
Collection: IIT Campus Aerial photographs, 1940-2002

Title: The Cycle, 1938
Creator: Armour Institute of Technology
Date: 1938
Description: Volume 26 of The Cycle, the 1938 yearbook for the Armour Institute of Technology. The Armour Institute of Technology yearbooks was known by...
Show moreVolume 26 of The Cycle, the 1938 yearbook for the Armour Institute of Technology. The Armour Institute of Technology yearbooks was known by three different titles: Integral (1898-1910), Senior Class Book (1911-1912), and The Cycle (1913-1940). A 1902 volume of Integral is not a part of Galvin Library collections; it is uncertain of a yearbook was published that year. Publication of the Armour Institute ceased in 1941, when the Armour Institute of Technology merged with the Lewis Institute to form Illinois Institute of Technology.
Sponsorship: Scanning of the Armour Institute of Technology yearbooks was supported in part by an award from the Illinois State Historical Records Advisory Board, through funding from the National Historical Publications and Records Commission, National Archives and Records Administration.
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Collection: Armour Institute of Technology yearbooks, 1898-1940

Title: The Cycle, 1934
Creator: Armour Institute of Technology
Date: 1934
Description: Volume 22 of The Cycle, the 1934 yearbook for the Armour Institute of Technology. The Armour Institute of Technology yearbooks was known by...
Show moreVolume 22 of The Cycle, the 1934 yearbook for the Armour Institute of Technology. The Armour Institute of Technology yearbooks was known by three different titles: Integral (1898-1910), Senior Class Book (1911-1912), and The Cycle (1913-1940). A 1902 volume of Integral is not a part of Galvin Library collections; it is uncertain of a yearbook was published that year. Publication of the Armour Institute ceased in 1941, when the Armour Institute of Technology merged with the Lewis Institute to form Illinois Institute of Technology.
Sponsorship: Scanning of the Armour Institute of Technology yearbooks was supported in part by an award from the Illinois State Historical Records Advisory Board, through funding from the National Historical Publications and Records Commission, National Archives and Records Administration.
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Collection: Armour Institute of Technology yearbooks, 1898-1940

Title: Design Direction, Book 2
Creator: Henry, Mary Dill, 1913-2009
Date: 1946
Description: Design Direction was Mary Henry's 1946 thesis for her graduate degree at the Institute of Design. The project, completed in collaboration with...
Show moreDesign Direction was Mary Henry's 1946 thesis for her graduate degree at the Institute of Design. The project, completed in collaboration with Emerson Woelffer, was based on a class for beginning students taught by Woelffer at ID. The course consisted of 18 exercises exploring the basic elements of design, each of which is represented in Henry's Design Directions. Book 1 consists of the design exercises themselves, Book 2 contains the textual component of the project.
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Collection: Mary Dill Henry Papers, 1913-2021

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1964
Creator: Brandt & Associates
Date: 1964
Description: Aerial photograph of the Illinois Institute of Technology campus, looking north.
Collection: IIT Campus Aerial photographs, 1940-2002

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1964
Creator: Brandt & Associates
Date: 1964
Description: Aerial photograph of the Illinois Institute of Technology campus, looking north.
Collection: IIT Campus Aerial photographs, 1940-2002

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1967
Creator: Brandt & Associates
Date: 1967
Description: Aerial photograph of the Illinois Institute of Technology campus, looking north.
Collection: IIT Campus Aerial photographs, 1940-2002

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, ca. 1955-1959
Date: 1955-1959
Description: Aerial photograph of the Illinois Institute of Technology campus, looking southwest. Photographer unknown. Date of photograph unknown. Date...
Show moreAerial photograph of the Illinois Institute of Technology campus, looking southwest. Photographer unknown. Date of photograph unknown. Date range listed is approximate.
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Collection: IIT Campus Aerial photographs, 1940-2002

Title: Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1957
Date: 1957
Description: Aerial photograph of the south portion of the Illinois Institute of Technology campus, looking south. Photographer unknown.
Collection: IIT Campus Aerial photographs, 1940-2002

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