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Bimetallic bars with local control of composition by three-dimensional printing

Techapiesancharoenkij, Ratchatee, 1979-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 112 p.; 1551479 bytes; 1998869 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
76.83619%
Three Dimensional Printing (3DP) is a process that enables the fabrication of geometrically complex parts directly from computer-aided design (CAD) models. The success of 3DP as an alternative manufacturing technology to bulk machining of materials for complex parts has been demonstrated. By proof of concept, 3DP has demonstrated the ability to create parts with Local Control of the Composition (LCC). LCC allows tailoring the material properties in regions of a part for functional purposes. In this work, LCC was studied and demonstrated by fabricating bimetallic bars consisting of two layers of Fe-Ni alloys with different composition and, hence, different thermal expansion properties; the coefficient of thermal expansion (CTE) of Fe-Ni system is sensitive to its composition. Two types of the binder/dopant slurries were made for making the LCC bars. One type consisted of dispersions of Fe₂O₃ particles in water, and the other consisted of dispersion of NiO in water. The LCC bars were successfully made by printing the Fe₂O₃/NiO slurries into Fe-30Ni base powders. After heat treatment to impart strength to the printed bars, the bars were successfully retrieved from unbound powders. The bars, then, were annealed at 1400 ⁰C for 2 hours for sintering and homogenization. The final composition of the base powders were changed accordingly. In the layers on which an Fe₂O₃ slurry was printed...

Grain size effects on the fatigue response of nanocrystalline materials

Hanlon, Timothy, 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 158 p.; 5653368 bytes; 11346872 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
77.31098%
The resistance of metals and alloys to fatigue crack initiation and propagation is known to be influenced significantly by grain size. Based on a wealth of experimental results obtained from microcrystalline metals, where the grain size is typically greater than 1 um, it is widely recognized that an increase in grain size generally results in a reduction in the fatigue endurance limit. On the other hand, a coarser grain structure can lead to an increased fatigue threshold stress intensity factor range, as well as a decrease in the rate of fatigue crack propagation. The relevance of these trends to ultra-fine-crystalline metals (grain size between 100 nm and 1000 nm) and nanocrystalline metals (grain size less than 100 nm) is relatively unknown. Such lack of understanding is primarily a consequence of the paucity of experimental data on the fatigue response of metals with very fine grains. In this work, the fatigue behavior of electrodeposited, fully dense, nanocrystalline pure Ni, with average and total range of grain sizes well below 100 nm, was examined. The fatigue response of nanocrystalline Ni was also compared with that of ultra-fine-crystalline and microcrystalline Ni wherever appropriate. It was found that grain refinement to the nanocrystalline regime generally leads to an increase in resistance to failure under stress-controlled fatigue whereas a deleterious effect was seen on the resistance to fatigue crack growth. To explore the generality of the above trends...

Microdebonding test for measuring shear strength of the fiber/matrix interface in composite materials

Grande, Dodd Harrison
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 139 leaves; 6113301 bytes; 6113057 bytes; application/pdf; application/pdf
ENG
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86.81816%
by Dodd Harrison Grande.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1983.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE; Includes bibliographical references.

Commercial applications of nanostructures created with ordered porous alumina

Wells, Brendan Christopher, 1979-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 87, [1] leaves; 5686970 bytes; 5696780 bytes; application/pdf; application/pdf
EN_US
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77.01267%
In the drive from microfabrication to nanofabrication, porous alumina templates may play a key role in technological evolution. Under the right processing conditions, ordered pores can grow in anodic aluminum oxide, which is a high strength, thermally and electrically insulating material. There are many potential applications for porous alumina templates, ranging from the simple fabrication of nanostructure arrays to the more complex processing of components for end-user products such as nano-integrated circuits and gas sensors. Porous alumina templates can also be processed to have long-range pore ordering on an entire twelve-inch silicon wafer, which may be of unique benefit to processes requiring such pore precision, such as parallel electron beam lithography. The high aspect ratios which can be attained through porous alumina template technology may also offer unique advantages in applications such as field-emission-based devices. As a durable high strength material, porous alumina templates are not limited by extreme process conditions, further extending the reach of their application. The vast array of applications allows the technology to be financially attractive inside business models ranging from sustaining to disruptive innovation. Porous alumina template technology has the necessary multitude and diversity of attributes to play a crucial role in the future of nanotechnology.; by Brendan Christopher Wells.; Thesis (M. Eng.)--Massachusetts Institute of Technology...

Self-healing properties of water filtration membranes containing amphiphilic comb polymer

Devereaux, Caitlin Albright, 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 120 p.; 7511014 bytes; 7525820 bytes; application/pdf; application/pdf
EN_US
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76.88495%
(cont.) and filtration experiments, as well as other characterization techniques. Surface analysis is accomplished via x-ray photoelectron spectroscopy (XPS). Membrane samples are cleaned (in hydrogen peroxide or chromic-sulfuric acid (Chromerge)) and/or annealed (in 90⁰C deionized water), and their elemental surface composition and specific carbon binding environments are determined by XPS. Filtration experiments are done by alternating feed solutions of deionized water and a foulant (either bovine serum albumin or an oil/water emulsion). The flux of the feed solution is measured before fouling, during fouling, and after fouling, to determine the extent of fouling recovery. Also, the compositions of the permeates are analyzed via ultraviolet-visible spectroscopy to determine the rejection coefficient of the membrane. The data presented in this thesis show that PVDF blend membranes containing P(MMA-r-POEM) are capable of generating a fresh surface layer of PEO multiple times, even after extended cleaning sessions using concentrated acid. Membranes of varying thickness are shown to exhibit PEO-regenerative abilities, but it appears that thick membranes have better fouling recovery than thinner, filtration-series membranes. Also, it is found that a blend membrane stripped of all of its surface PEO (by a 24-hour-long exposure to Chromerge) is able to restore PEO to its surface with roughly 24 hours of annealing ...; Freshwater shortages are a tremendous problem for certain areas of the world...

Nanomechnics of crystalline materials : experiments and computations

Van Vliet, Krystyn J. (Krystyn Joy), 1976-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 165 leaves; 8532263 bytes; 8532072 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
76.94809%
In this thesis, experimental, computational and analytical approaches are employed to examine systematically the mechanisms of deformation in crystalline materials. Such insight can be used to exploit and avoid contact in actuator and sensor applications, to derive mechanical properties for engineering of materials, and to investigate the fundamental role of defects. Here, localized mechanical contact of material surfaces is utilized to elucidate the effects of length scales on the transition from elastic (reversible) to plastic (irreversible) deformation. As the mechanical response of a material can be described by parameters which range from empirical constitutive (stress-strain) relations to fundamental descriptions of atomic interactions, the deformation response can be related to global mechanical properties such as yield strength, as well as to local phenomena such as dislocation nucleation. The concurrent design and implementation of experiments including micro- and nanoindentation and uniaxial compression, in situ experiments on a model, two-dimensional crystalline analogue, and computational modeling at the continuum (finite element) and atomistic (molecular dynamics) levels presented herein provide a unique opportunity to develop and validate hypotheses and analytical algorithms. Indeed...

Rehardenable materials system with diffusion barrier for three-dimensional printing

Yuen, Cheong Wing, 1972-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 197 p.; 16760335 bytes; 16760143 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
76.967065%
Three-Dimensional Printing (3DP) is a solid freeform fabrication process being developed for the direct manufacture of functional tooling and prototypes from a computer solid model. One of its many important applications is the fabrication of metal tooling for plastic injection molding. In order to achieve a fully dense 3DP metal tool, the sintered powder skeleton is infiltrated with a molten alloy, which has a melting point lower than the skeleton material. However, the choices of materials systems are limited by the interactions of the metal powders and infiltrants during the infiltration process. Currently, the materials system with the best wear resistance for 3DP metal tooling consists of 420 stainless steel powder and bronze infiltrant. However, it only has an overall hardness of 25 HRC because the bronze infiltrant is soft and not hardenable. A hardenable 3DP metal system is desirable. The main goals of this thesis research are: 1) to improve the flexibility of choice of metal powders and infiltrants by using a diffusion barrier to isolate them; and 2) to demonstrate the diffusion-barrier approach with steel and hardenable copper-alloy infiltrant. The model materials systems in this study consist of stainless steel and tool steel powder skeletons with Cu-20Ni-20Mn infiltrant. It was demonstrated that TiN coating deposited on steel substrates by CVD successfully prevented the reaction between the steel and molten Cu-20Ni-20Mn at 1200° C. In general...

Alloy design or three-dimensional printing of hardenable tool materials

Guo, Honglin, 1965-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 174 leaves; 8524668 bytes; 8524474 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
77.337954%
Three-dimensional printing (3DP) is a state-of-the-art manufacturing technology, One of its many important applications is to fabricate the metal tooling for plastic injection molding. In order to achieve a fully dense 3DP metal tool, the current 3DP process involves five steps: printing, debinding, sintering, liquid metal infiltration and heat treatment. Due to the infiltration requirement, all 3DP tools made to date are composed of a high-strength skeleton material and a low-strength infiltrant. The search for a hardenable/hard 3DP system is the mission of this dissertation. Five major accomplishments can be found in the dissertation: (1) development of the 420/bronze material system for 3DP tooling; (2) development and optimization of the post-processing of the system; (3) development of a computer model simulating the interaction of powder/liquid infiltrant; (4) computer-aided material system design and (5) methodology exploration of the material system development.The 420/bronze material system with a minimum reaction was developed experimentally, by screening 30 potential material systems. Compared to the initial 3DP and reactive system, the system strength was significantly improved. More than 50 3DP injection tools have been fabricated using this material system. A 3DP tool made of the 420/bronze system has been used to mold more than one hundred thousand plastic products without major repairing of the tool. It was the first time that an injection mold was made of 60 vol% 420 and 40 vol% bronze. The system was a milestone in the 3DP material system development. In addition...

Investigating the molecular origins of biocompatibility : intermolecular interactions between human serum albumin and various chemically modified surfaces via high resolution force spectroscopy

Rixman, Monica Anne, 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 215 p.; 8567989 bytes; 8567796 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
77.018623%
The first step in two of the most troublesome biological responses to the implantation of blood-contacting biomaterials, i.e. thrombosis and inflammation, is the adhesion of blood plasma proteins to the biomaterial surface, which may then initiate platelet adhesion and activation, and thereby set in motion a cascade of adverse host responses. If devices could be developed that prevent that first step from occurring altogether, a new generation of "stealth" biomaterials would be born. Such was the motivation of this project, which sought to investigate the constituent intermolecular interaction forces governing protein adhesion to biomaterials, using the technique of high resolution force spectroscopy. The model protein chosen for our study was human serum albumin (HSA), the smallest and most abundant blood protein in the human body, and typically the first to adsorb to a blood-contacting, implanted device. In the first stage of our investigation, HSA was covalently grafted to a nanosized probe tip at the end of a soft, microfabricated cantilever force transducer. The intermolecular interaction potential, U(D), was recorded between the HSA-modified probe tip and four different model surfaces, including: 1) gold, 2) a hydrophobic, CH3-terminated alkanethiol self-assembling monolayer (SAM)...

An investigation of the high cycle fatigue behavior of bovine trabecular bone

Hastings, Abel Z., 1973-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 79 p.; 2385407 bytes; 2385215 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
76.944478%
Fractures can be caused by fatigue loading due to prolonged exercise and age-related fragility. Fatigue loading causes microdamage in bone that leads to both a loss of stiffness and strength. Some engineering materials, such as steels, have a fatigue limit, which is represented by a stress plateau in the stress-life (S-N) curve. When loaded to levels below the stress plateau, these materials have an infinite fatigue life. Other materials, such as aluminum, do not exhibit a fatigue limit. For these materials, the endurance limit is defined as the stress amplitude corresponding to a somewhat arbitrary large number of cycles of fatigue (e.g. various texts suggest 10⁶ to 10⁸ cycles ). In previous work on compressive fatigue of bovine trabecular bone, it was hypothesized that there was a fatigue limit at a normalized stress, [Delta] [rho]/E₀, of approximately 0.0035. This study tested this hypothesis by fatigue testing bovine trabecular bone loaded to one of four normalized stresses ranging from 0.0015 to 0.0035. Failure was defined as a 10% loss in the secant modulus of the specimen. The data show that the rate of decrease of modulus reduction per cycle increased with increasing normalized stress. A fatigue limit in bovine trabecular bone was not found. While a threshold below which the fatigue life is infinite was not found...

Micro and nano mechanics of materials response during instrumented frictional sliding

Bellemare, Simon C. (Simon Claude)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 109 p.
ENG
Relevância na Pesquisa
86.9175%
Over the past decade, many computational studies have explored the mechanics of instrumented normal indentation. In contrast, very few studies have investigated quantitative aspects of frictional sliding contact in the elasto-plastic regime. In this thesis, a new framework was developed to establish relationships between the frictional sliding response, material properties and contact parameters. Dimensional analysis enabled to define scaling variables and dimensionless functions. Finite element methods were used to simulate the process of steady-state frictional sliding and evaluate the dimensionless functions. In frictional sliding, the representative plastic strain was found to be more than four times as large as in normal indentation. Further comparison with indentation indicated a three fold increase in the maximum pile-up height and an increased influence of the strain hardening on hardness. Experimental studies were conducted with and without a liquid lubricant in selected material systems. Quantitative agreements with numerical predictions were observed in all cases. The strong influence of the strain hardening exponent on the pile-up height was illustrated from frictional sliding results obtained in copper and copper-zinc specimens of different grain sizes.; (cont.) Also...

Stress corrosion cracking and hydrogen embrittlement of thick section high strength low alloy steel

Needham, William Donald
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 277 leaves
ENG
Relevância na Pesquisa
77.015215%
An experimental study was conducted to evaluate the corrosion performance of weldments of a high strength low alloy(HSLA) steel in a simulated seawater environment. This steel, designated HSLA80, was developed by the United States Navy for use in ship structural applications. Stress corrosion CRACKING(SCC) and hydrogen embrittlement(HEM) were investigated by conducting 42 Wedge-Opening load(WOL) tests as a function of stress intensity and corrosion potential and 33 Slow Strain Rate(SSR) tests as a function of strain rate and corrosion potential. The corrosion potentials were chosen to simulate the environmental conditions of free corrosion, cathodic protection and hydrogen generation. The results from this investigation indicated that HSLA 80 base metal and weldments were susceptible to hydrogen assisted cracking(HAC) in a seawater environment under conditions of continuous plastic deformation and triaxial stress in the presence of hydrogen. The heat-affected zone of the weldment was found to be the most susceptible portion of the weld joint. A lower bound was established for the critical stress intensity for stress corrosion cracking for HSLA 80 base metal and weldments.; by William Donald Needham.; Thesis (Ocean E.)--Massachusetts Institute of Technology...

Mechanical behavior of dip-brazed aluminum sandwich panels

Hohmann, Brian P. (Brian Patrick)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 161 leaves
ENG
Relevância na Pesquisa
77.1503%
An experimental study was carried out to determine the mechanical behavior of sandwich panels containing cellular cores of varying shape. Compression and four point bend tests were performed on sandwich panels with square and triangular honeycomb cores. These honeycombs were made of perforated aluminum sheet of repeating diamond and hexagonal patterns. The sandwich panel assemblies were joined via dip brazing. Defects were introduced into some panels to quantify the effect on strength and stiffness. Hybrid sandwich panels, consisting of foam material in the void spaces of the square and triangular cells were evaluated for the effect on the defect tolerance of the structures. The results showed that sandwich panels with diamond shaped cores had compressive strengths approximately four times greater than hexagonal shaped cores. In four point bending the diamond cores were approximately twice as stiff as cores made from hexagonal patterned sheet. The introduction of defects lowered strength by about 30% for diamond cores in compression, and about 15% for hexagonal cores. In four point bending this strength reduction was not as significant due to shear stresses damaging periodicity at a faster rate than in compression.; (cont.) The use of foam within the cells resulted in higher absolute peak compression and flexure loads...

Sintering and joining of low temperature co-fired tungsten and aluminum oxide

Boonyongmaneerat, Yuttanant
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 189 p.
ENG
Relevância na Pesquisa
76.835366%
Conventional methods used to fabricate co-fired tungsten/alumina composites usually rely on high temperature processing (>1500C). As it would be beneficial or even necessary for some applications to produce such composites at relatively low firing temperatures, low-temperature processing techniques and the attendant knowledge of processing-property relationships need to be developed. In this thesis, a set of experiments and simulations are performed to obtain a better understanding of sintering and joining of the tungsten/alumina system processed at temperatures near or below 12000C. The technique of activated sintering for tungsten is investigated, whereby a minimal content of additives enables low firing temperatures through a change in the sintering mechanism for tungsten. Tungsten compacts produced by this method are found to sinter only to the "initial stage" and are characterized by high residual porosity level. Hardness and fracture toughness of such partially-sintered materials are examined experimentally and analytically, and dependence of mechanical properties on the relative particle neck size is observed. Various studies are carried out to examine both fundamental and practical aspects of joining co-fired tungsten/alumina.; (cont.) First...

Property determinants of dextran:polyethylene glycol adhesive sealants

Shazly, Tarek (Tarek Michael)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 100 leaves
ENG
Relevância na Pesquisa
77.08903%
Internal surgical intervention necessitates the intentional wounding of tissue. In certain clinical procedures, the desired wound healing response requires the use of closure techniques, such as suturing or stapling of disjoined tissues. Risk factors associated with these techniques are largely attributed to the discrete nature of the mechanical forces arising in the tissues. Adhesive sealants can mitigate risk by imparting a continuous stress distribution to tissues upon closure, as opposed to destructive stress concentrations. A novel class of dextran:polyethylene glycol hydrogels are a potential alternative to the limited selection of available adhesive sealants. Multiple compositional variations are available for both the dextran and polyethylene glycol components, making a wide range of clinically relevant material properties achievable. Key material properties determining sealant efficacy include hydration and degradation in an aqueous medium, elastic modulus, adhesion strength to tissue, and biocompatibility. Relationships between these pertinent properties and available compositional variations are determined for dextran:polyethylene glycol materials.; (cont.) Gravimetric, mechanical and biological testing reveal the following compositional determinants of material properties in dextran:polyethylene glycol copolymers: constituent molecular complexity dictates material hydration and degradation...

Nanomechanics and ultrastructural studies of cortical bone : fundamental insights regarding structure-function, mineral-organic force mechanics interactions, and heterogeneity

Tai, Kuangshin
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 256 leaves
ENG
Relevância na Pesquisa
77.205317%
Although the mechanics of bone has been studied extensively at the micro- and macro-scale, the nano-scopic level is perhaps the most illuminating as this is the length scale at which the individual constituents interact. Bone is made primarily up of type I collagen, hydroxyapatite mineral, a variety of non-collagenous proteins, and water. A multitechnique experimental and modeling approach methodology was used break down several of the deformation mechanisms that exist in bone at the nanoscale including the effect of mineral content, cohesive-frictional plasticity, increased ductility through mechanical heterogeneity, and intermolecular forces. To show that mineral content had a significant effect on both nanomechanical properties and ultrastructural deformation mechanisms of bone, partial and complete demineralization was carried out to produce samples ranging from -0-58 wt.% mineral content. Nanoindentation experiments perpendicular to the osteonal axis found a 4-6x increase in stiffness for the -58 wt.% sample compared to the completely demineralized -~0 wt.% samples. These results are discussed in the context of in situ and post-mortem AFM imaging studies which shed light on nanoscale mechanisms of deformation including collagen fibril deformation and pressure induced structural transitions of the mineral component.; (cont.) A finite element elastic-plastic continuum model was able to predict the nanomechanical properties of the different samples on loading and unloading. In addition...

Indentation of plastically graded materials

Choi, In-Suk, Ph. D. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 126 p.
ENG
Relevância na Pesquisa
87.24146%
The introduction of certain controlled gradients in plastic properties is known to promote resistance to the onset of damage at contact surfaces during some tribological applications. Gradients in composition, microstructure and plastic properties can also be deleterious to contact-damage resistance in some situations. In order to realize such potentially beneficial or deleterious effects of plastic property gradients in tribological applications, it is essential first to develop a comprehensive understanding of the effects of yield strength and strain hardening exponent on frictionless normal indentation. To date, however, systematic studies of plasticity gradient effects on indentation response have not been completed. A comprehensive parametric study of the mechanics of indentation of plastically graded materials is completed in this work by recourse to finite element (FE) computations. On the basis of a large number of detailed computational simulations, a general methodology for assessing instrumented indentation response of plastically graded materials is formulated so that quantitative interpretations of depth-sensing indentation experiments could be performed. The specific case of linear gradient in yield strength is explored in detail.; (cont.) The FE analysis leads to a universal dimensionless function to predict load displacement curves for plastically graded engineering materials. Experimental validation of the analysis is performed by choosing the model system of an electrodeposited nanostructured Ni-W alloy...

Environmentally benign manufacturing of three dimensional integrated circuits; Manufacturing of three dimensional integrated circuits

Somani, Ajay
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 268 p.
ENG
Relevância na Pesquisa
76.87794%
Along with scaling down in size, novel materials have been introduced into the semiconductor industry to enable continued improvements in performance and cost as predicted by Moore's law. It has become important now more than ever to include an environmental impact evaluation of future technologies, before they are introduced into manufacturing, in order to identify potentially environmentally harmful materials or processes and understand their implications, costs, and mitigation requirements. In this thesis, we introduce a methodology to compare alternative options on the environmental axis, along with the cost and performance axes, in order to create environmentally aware and benign technologies. This methodology also helps to identify potential performance and cost issues in novel technologies by taking a transparent and bottoms-up assessment approach. This methodology is applied to the evaluation of the MIT 3D IC technology in comparison to a standard CMOS 2D IC approach. Both options are compared on all three axes - performance, cost and environmental impact.; (cont.) The "handle wafer" unit process in the existing 3D IC technology, which is a crucial process for back-to-face integration, is found to have a large environmental impact because of its use of thick metal sacrificial layers and high energy consumption. We explore three different handle wafer options...