The objectives of this work are to discuss multiscale models that are used to characterize the constitutive relations of the granular composite materials with dual functions. This is accomplished by the use of ab initio methods to obtain the constitutive relations of the structural energetic materials without conducting tests. First, it is necessary to study the quantum many body problem to quantitatively determine the internal energy of the material when subjected to different strain conditions. It is impossible to obtain an exact solution to the quantum many body problem that is modeled by the Schrödinger's equations with the current technology. It is possible to solve these equations approximately by the density functional theory which yields only energies at absolute 0ºK. Thus it becomes necessary to add both the lattice thermal contributions and electron thermal contribution. Then, resulting energy is used to bridge to the continuum level and obtain the constitutive equations. This is the procedure that is used in this work. The issues of the constitutive equations form the focus of this thesis. More specifically, the scope of the thesis is further restricted to analyze the constitutive equations of specific mixtures of nickel, aluminum with PTFE or Teflon as the binder. It is to be noted that the equations of state forms only a part of the complete constitutive relationships. This thesis presents solutions to the following problems: (1) Determination of the thermodynamically complete equation of state of the binder and the energetic material PTFE or Teflon, from ab initio methods based on the density functional theory. (2) Determination of the equations of state of the granular composite or the mixture of nickel, aluminum and PTFE from ab initio methods. (3) Determination of the complete constitutive equation of aluminum, from ab initio methods, under conditions of finite deformations, with principle of objectivity, material symmetry conditions and polyconvexity of the strain energy. All results are compared to test results whenever they are available.

The past twenty years have seen the successful characterization and computational modeling efforts by the smart materials community to better understand the Shape Memory Alloy (SMA). Commercially available numerical analysis tools, coupled with powerful constitutive models, have been shown to be highly accurate for predicting the response of these materials when subjected to predetermined loading conditions. This thesis acknowledges the development of such an established analysis framework and proposes an expanded design framework that is capable of accounting for the complex coupling behavior between SMA components and the surrounding assembly or system. In order to capture these effects, additional analysis tools are implemented in addition to the standard use of the non-linear finite element analysis (FEA) solver and a full, robust SMA constitutive model coded as a custom user-defined material subroutine (UMAT). These additional tools include a computational fluid dynamics (CFD) solver, a cosimulation module that allows separate FEA and CFD solvers to iteratively analyze fluid-structure interaction (FSI) and conjugate heat transfer (CHT) problems, and the addition of the latent heat term to the heat equations in the UMAT to fully account for transient thermomechanical coupling. Procedures for optimizing SMA component and assembly designs through iterative analysis are also introduced at the highest level. These techniques are implemented using commercially available simulation process management and scripting tools. The expanded framework is demonstrated on example engineering problems that are motivated by real morphing structure applications, namely the Boeing Variable Geometry Chevron (VGC) and the NASA Shape Memory Alloy Hybrid Composite (SMAHC) chevron. Three different studies are conducted on these applications, focusing on component-, assembly-, and system-level analysis, each of which may necessitate accounting for certain coupling interactions between thermal, mechanical, and fluid fields. Output analysis data from each of the three models are validated against experimental data, where available. It is shown that the expanded design framework can account for the additional coupling effects at each analysis level, while providing an efficient and accurate alternative to the cost- and time-expensive legacy design-build-test methods that are still used today to engineer SMA actuated morphing aerostructures.

Time- and rate-dependent materials such as polymers, bituminous materials, and soft materials clearly display all four fundamental responses (i.e. viscoelasticity, viscoplasticity, viscodamage, and healing) where contribution of each response strongly depends on the temperature and loading conditions. This study proposes a new general thermodynamic-based framework to specifically derive thermo-viscoelastic, thermo-viscoplastic, thermo-viscodamage, and micro-damage healing constitutive models for bituminous materials and asphalt mixes. The developed thermodynamic-based framework is general and can be applied for constitutive modeling of different materials such as bituminous materials, soft materials, polymers, and biomaterials. This framework is build on the basis of assuming a form for the Helmohelotz free energy function (i.e. knowing how the material stores energy) and a form for the rate of entropy production (i.e. knowing how the material dissipates energy). However, the focus in this work is placed on constitutive modeling of bituminous materials and asphalt mixes. A viscoplastic softening model is proposed to model the distinct viscoplastic softening response of asphalt mixes subjected to cyclic loading conditions. A systematic procedure for identification of the constitutive model parameters based on optimized experimental effort is proposed. It is shown that this procedure is simple and straightforward and yields unique values for the model material parameters. Subsequently, the proposed model is validated against an extensive experimental data including creep, creep-recovery, repeated creep-recovery, dynamic modulus, constant strain rate, cyclic stress controlled, and cyclic strain controlled tests in both tension and compression and over a wide range of temperatures, stress levels, strain rates, loading/unloading periods, loading frequencies, and confinement levels. It is shown that the model is capable of predicting time-, rate-, and temperature-dependent of asphalt mixes subjected to different loading conditions.

This dissertation analyzes the ways in which Mennonite rhetors used historical narratives to construct a coherent Mennonite identity in the 1940s and 1950s. During this era, U.S. American Mennonites faced a multitude of threats to their sectarian group identity, most especially during the Second World War. In response to these exigencies, a group of American Mennonite historians, who would later become known as the "Goshen Circle" of Mennonite historiography, discursively wove a new subject identity--known as a monogenic conception of Anabaptism--which reinforced Mennonite group identity and legitimated Mennonite faith convictions to outsiders. Until this point, Mennonite historians, sociologists, and others have only considered the discourse of the Goshen Circle along narrow lines. On the one hand, many historians have rejected the Goshen Circle discourse as simply partisan, and therefore "bad," history. On the other hand, other scholars still think that the historical work of the Goshen Circle simply "recovered" or "rediscovered" elements of Anabaptism which were implicit in the Mennonite tradition. In contrast to these positions, this dissertation argues that the establishment of an Anabaptist subjectivity was a rhetorical achievement and analyzes how several texts attempted rhetorical interventions to transform the already-given historical situations faced by twentieth-century Mennonites. I substantiate this claim by utilizing Maurice Charland's (1987) theory of constitutive rhetoric to analyze the discourse of three primary figures of Goshen Circle monogenic Anabaptist historiography: Harold S. Bender, Guy F. Hershberger, and J.C. Wenger. My analysis demonstrates: how these rhetors asserted the existence of a unified Anabaptist-Mennonite people, how they used "transhistorical" narratives to build networks of identification between sixteenth-century Anabaptists and their supposed twentieth-century Mennonite descendants, and how their constitutive rhetoric positioned Mennonites to take material action to confirm their place in the Anabaptist narrative.

Análises numéricas confiáveis do comportamento mecânico de materiais como borrachas, dependem muito de uma calibração precisa do modelo constitutivo hiperelástico utilizado. Estes modelos são calibrados ajustando as curvas teóricas aos dados experimentais, obtidos por meio de ensaios usuais. Em muitos casos as amostras de matéria prima desses elastômeros já não se encontram disponíveis ou é impossível fabricar os corpos de prova requeridos. O objetivo deste trabalho é verificar a possibilidade de encontrar constantes constitutivas testando o próprio componente, ao invés dos usuais ensaios de tração, compressão e cisalhamento. A abordagem proposta consiste em criar uma rotina de programação associada a uma função custo onde, a partir de uma estimativa inicial de constantes constitutivas, sejam realizados processos iterativos de otimização buscando aproximar as curvas de força × deslocamento teórica e experimental. Um componente automotivo será utilizado nos estudos e dois modelos constitutivos hiperelásticos serão testados. As equações de tensões nominais dos modelos hiperelásticos serão utilizadas para predizer o comportamento teórico dos ensaios usuais, de forma a verificar a qualidade das constantes obtidas. Conclui-se que é possível utilizar o ensaio da própria peça para caracterizar o material hiperelástico, com resultados comparáveis aos que seriam obtidos com os ensaios típicos para esta aplicação. / The reliable numerical analysis of the mechanical behavior of rubber-like materials depends strongly on accurately calibrated hyperelastic constitutive models. Such models are calibrated by fitting theoretical curves against experimental data obtained in well known tests. In many cases samples of the original elastomer are no longer available or it is impossible to manufacture the specimens required by the standard tests. The aim of this work is verify the possibility of finding the constitutive constants by testing the actual component instead of the usual tensile, compression and shear tests. The proposed approach consists in creating a programming routine with a cost function that, starting from an initial estimate of the constitutive constants, iterate through an optimization algorithm in order to fit the theoretical force × displacement curves to the experimental ones. An automotive component will be used during the studies and two hyperelastic constitutive models will be tested. The nominal stress equations for the hyperelastic models are used to predict the standard tests behavior, to assess the quality of the constants obtained. The results shown that is possible to characterize an hyperelastic material by testing the actual component, with results comparable to those which would be obtained with standard tests.

A presença de compostos orgânicos no solo proporciona o desenvolvimento de uma fase adicional nos poros, imiscível com a fase aquosa e gasosa pré-existentes. A característica de imiscibilidade destes compostos, denominados de fase livre não aquosa (“nonaqueos phase liquid” – NAPL), torna a avaliação de um solo contaminado por tais substâncias bastante complexa. Dentre as substâncias pertencentes a este grupo NAPL, destacam-se os produtos derivados do petróleo. As propriedades mais importantes na avaliação de um solo contaminado por NAPL são suas relações constitutivas. Uma destas propriedades relaciona a sucção dos fluídos com suas respectivas saturações, enquanto que a outra relaciona a condutividade relativa dos fluidos com a saturação de cada um destes fluidos. A partir da curva de retenção de um solo contaminado, é possível quantificar de forma indireta a relação condutividade relativa-saturação. Todavia, a obtenção desta curva de retenção para um solo contaminado por NAPL é bastante complexa e está em desenvolvimento, exigindo cuidados na sua determinação. Para isso, assume-se que no interior de um poro contendo água, óleo e ar, o contaminante estará preferencialmente localizado entre a água e o ar. Isto é determinante ao admitir-se que a saturação da água Sw é uma função da sucção mátrica desenvolvida entre a água e o óleo e a saturação total dos líquidos St, (soma da saturação da água e do óleo) é dependente da sucção mátrica gerada entre o óleo e o ar. Esta hipótese possibilita a obtenção das curvas de retenção para sistemas trifásicos ar-NAPL-água a partir dos sistemas bifásicos NAPL-água e ar-NAPL. Assim sendo, o objetivo deste trabalho é desenvolver, a partir de um oedômetro com controle de sucção, um equipamento, denominado de célula multifásica, que permita o controle independente das pressões do ar, do NAPL e da água. Especificamente, este equipamento permitirá a determinação das curvas de retenção para sistemas bi e trifásicos. Para atingir esta meta, foi necessário transformar uma pedra porosa cerâmica comum em uma pedra porosa hidrofóbica (repelente à água), através de um tratamento químico da pedra porosa convencional em uma solução contendo uma substância comercialmente conhecida como Glassclad 18. Este novo equipamento permite o monitoramento da variação do volume de água e de óleo no interior de uma amostra de solo para diversas pressões capilares. Ensaios preliminares foram realizados em uma mistura composta de 70% de um solo arenoso e 30% de um solo argilo-arenoso, sendo o primeiro coletado no estado do Rio Grande do Sul enquanto que o segundo em Santa Catarina. Ambos os solos possuem propriedades físicas bem conhecidas. / The presence of organic compounds in the soil provides the development of an additional phase in the pore space, immiscible with the preexisting water and gaseous phases. This characteristic of immiscibility of such substances, called nonaqueos phase liquids – NAPL’s, turns the evaluation of a soil contaminated by these substances sufficiently complex. Among the substances pertaining to this group, called NAPL, the petroleum products are distinguished. The most important properties in the evaluation of a soil contaminated by NAPL are their constitutive relationships. One of these properties relates the pressure of the fluids with their respective saturations, while the other one relates the relative permeability of the fluids with the saturation of each one of these fluids. From the pressure-saturation constitutive relationship of a contaminated soil, it is possible to quantify indirectly the relative permeability-saturation relationship. However, the evaluation of the pressure-saturation relationship for a soil contaminated by NAPL is sufficiently complex and is in development, demanding considerable care in its determination. For this, it is assumed that, in the interior of a pore contaning water, oil and air, the organic liquid will be preferentially located between the water and air. That is imperative when assuming that water saturation of Sw is a function of the suction developed between the oil-water interface and the total liquid saturation St (sum of water saturation and oil saturation) is dependent of the suction generated between the airoil interfaces. This hypothesis makes possible the evaluation of the pressure-saturation relationship for the three-phase system air-NAPL-water from the two-phase systems NAPLwater and air-oil. Thus, the objective of this work is to develop, from the edometer with pressure control, another equipment, called the multiphase cell, that allows the independent control of the air, NAPL and water pressures. Specifically, this equipment will allow the determination of the pressure-saturation relationship for bi- and three-phase systems. To reach this goal, it was necessary to transform a standard ceramic porous stone in a hidrophobic porous stone (repellent to water), through a chemical treatment of the standard porous stone in a solution containing a substance commercially known as Glassclad 18. This new equipment allows the control of the volume changes of water and oil within a soil sample for different suction. Preliminary tests have been carried out with a mixture composed by 70% of sand and 30% of silt; the first material were collected in the state of the Rio Grande do Sul (Brazil) and the second in the state of Santa Catarina. Both materials have their physical properties well known.

A estimação de parâmetros de equações constitutiva viscoelásticas, tipicamente efetuada através de diferentes tipos de reômetros, pode ser uma tarefa árdua, especialmente no que diz respeito à estimação de parâmetros não lineares. Nas últimas décadas houve grande progresso no desenvolvimento de novas metodologias para caracterização de fluidos viscoelásticos na região de comportamento viscoelástico não linear e na simulação de escoamentos de fluidos viscoelásticos nesta região. Este trabalho tem como objetivo apresentar uma metodologia de estimação de parâmetros reológicos de equações constitutivas viscoelásticas baseada na comparação recursiva entre valores originados em experimentos com a modelagem em fluidodinâmica computacional do escoamento de referência. Esta metodologia apresenta como vantagem a possibilidade de estimar parâmetros a partir de dados originados em escoamentos mais representativos dos processos industriais, resultando em parâmetros com maior potencial de representar adequadamente o comportamento viscoelástico de um dado material nas suas condições típicas de aplicação. Dois estudos de caso foram implementados de forma a testar a metodologia: o escoamento de um fluido newtoniano entre placas paralelas e o escoamento de um fluido viscoelástico na saída do capilar. A estimação da viscosidade newtoniana foi baseada na comparação entre valores analíticos e numéricos para o gradiente de pressão ao longo do escoamento. A estimação do parâmetro não linear da equação constitutiva viscoelástica de Phan-Thien-Tanner (PTT) foi baseada na diferença entre os perfis de diâmetro numéricos com relação aos valores experimentais para o fenômeno de inchamento do filete de fluido ao emergir da saída do capilar, conhecido como inchamento do extrusado. O erro final obtido para o valor estimado da viscosidade newtoniana foi de 9 % com relação ao valor de referência. Para o parâmetro não linear do modelo PTT o erro para o valor estimado foi de 0,75 % com relação ao valor de referência obtido pela técnica de reometria rotacional. / The estimation of viscoelastic constitutive equations parameters, typically performed through different types of rheometers, can be an arduous task, especially as regards the estimation of nonlinear parameters. In recent years, there has been great progress in developing new methods for the characterization of viscoelastic fluids beyond the linear region and in the simulation of viscoelastic fluid flows in general. This work aims to present a methodology for estimation of rheological parameters of viscoelastic constitutive equations. The methodology is based on recursive comparison between experimentally measured fields with numerically computed ones by a computational fluid dynamics (CFD) model. This methodology has the advantage of estimating parameters through data coming from more representative flows of industrial processes, resulting in parameters with higher potential to represent the viscoelastic behavior of a given material under its typical conditions of application. Two case studies have been used to test this methodology: a steady state shear flow between two parallel plates of a Newtonian fluid and a viscoelastic fluid flow in a capillary. The estimation of Newtonian viscosity was based on the comparison between analytical and numerical values for the pressure gradient along the flow. The estimation of the nonlinear parameter of the viscoelastic constitutive equation Phan-Thien-Tanner was based on the difference between the experimental and numerical diameter profiles of the swelling of the fluid emerging from the capillary opening, known as extrudate swell. The final error obtained for the estimated value of Newtonian viscosity was 9 % compared to the reference value. For nonlinear parameter of PTT model, the error of the estimated value was 0.75 % compared to the reference value obtained through rotational rheometer technique.

Este trabalho apresenta uma metodologia para a inclusão de fenômenos dissipativos em relações constitutivas hiperelásticas. Embora seja dada ênfase para o efeito Mullins e histerese, esse procedimento pode ser aplicado a outros fenômenos como, por exemplo, de dano. Para isso, adota-se um modelo fenomenológico que inclui amolecimento em um modelo constitutivo hiperelástico através da pseudo-elasticidade, que permite que diferentes potenciais de energia possam ser utilizados em diferentes etapas do carregamento. Foram utilizados dois modelos hiperelásticos incompressíveis: Ogden e Hoss-Marczak. Para esse estudo, foram selecionados quatro diferentes materiais da literatura, três deles apresentavam apenas dados experimentais para tração uniaxial, enquanto o outro disponibilizou os ensaios de tração uniaxial, tração equibiaxial e cisalhamento puro. Foram selecionados dois parâmetros de amolecimento da literatura (Ogden e Roxburgh, 1999, e Dorfmann e Ogden, 2003) para modelar fenômenos dissipativos e então foram propostos novos parâmetros de amolecimento. Verificação gráfica dos resultados e um coeficiente de correlação (R2) foram utilizados para comparar o desempenho desses parâmetros. Os materiais foram considerados isotrópicos e incompressíveis e o carregamento quasi-estático para obtenção dos resultados. Alguns parâmetros propostos não capturaram o efeito dissipativo, outros superestimaram o amolecimento, enquanto os da literatura capturaram o efeito. Ao final, obteve-se resultados bastante satisfatórios para um dos parâmetros propostos, que se verificou ser uma generalização do modelo de Dorfmann e Ogden, 2003. / This work applies a methodology to include dissipative effects in hyperelastic constitutive relations. The paper focuses on the Mullins effect and hysteresis. However, the methodology can also be applied to other phenomena, like damage. Basically, it is a phenomenological inclusion of the softening behavior in a hyperelastic constitutive model using pseudo-elasticity, in which different energy potentials can be used in different steps of the loading. Two hyperelastic models were employed: Ogden’s and Hoss-Marczak’s models. Four different materials were modeled, three of them subjected to uniaxial tension only, and a fourth subjected to the three classical loadings, namely, uniaxial tension, equibiaxial tension and pure shear. Two softening parameters from the literature were implemented and new softening parameters were proposed. Graphical inspection and R2 correlation coefficient were used to compare the softening parameters. The materials were considered isotropic and incompressible, being subjected to quasi-static loading. Some of the proposed parameters did not captured the dissipative effect, other overestimate the softening, and those from the literature were able to capture the effects. Finally, very satisfying results were obtained with one the proposed softening parameters, which was a generalization of the one proposed by Dorfmann e Ogden, 2003.

abstract: Finite element simulations modeling the hydrodynamic impact loads subjected to an elastomeric coating were performed to develop an understanding of the performance and failure mechanisms of protective coatings for cavitating environments. In this work, two major accomplishments were achieved: 1) scaling laws were developed from hydrodynamic principles and numerical simulations to allow conversion of measured distributions of pressure peaks in a cavitating flow to distributions of microscopic impact loadings modeling individual bubble collapse events, and 2) a finite strain, thermo-mechanical material model for polyurea-based elastomers was developed using a logarithmic rate formulation and implemented into an explicit finite element code. Combining the distribution of microscopic impact loads and finite element modeling, a semi-quantitative predictive framework is created to calculate the energy dissipation within the coating which can further the understanding of temperature induced coating failures. The influence of coating thickness and elastomer rheology on the dissipation of impact energies experienced in cavitating flows has also been explored. The logarithmic formulation has many desired features for the polyurea constitutive model, such as objectivity, integrability, and additive decomposition compatibility. A review and discussion on the kinematics in large deformation, including a comparison between Lagrangian and Eulerian descriptions, are presented to explain the issues in building rate-dependent constitutive models in finite strains. When comparing the logarithmic rate with other conventional rates in test examples, the logarithmic rate shows a better conservation of objectivity and integrability. The modeling framework was validated by comparing predictions against temperatures measured within coatings subjected to a cavitating jet. Both the experiments and models show that the temperatures generated, even under mild flow conditions, raise the coating temperature by a significant amount, suggesting that the failure of these coatings under more aggressive flows is thermally induced. The models show that thin polyurea coatings synthesized with shorter molecular weight soft segments dissipate significantly less energy per impact and conduct heat more efficiently. This work represents an important step toward understanding thermally induced failure in elastomers subjected to cavitating flows, which provides a foundation for design and optimization of coatings with enhanced erosion resistance. / Dissertation/Thesis / Doctoral Dissertation Mechanical Engineering 2016

Submitted by Maria Suzana Diniz (msuzanad@hotmail.com) on 2015-11-23T13:12:31Z No. of bitstreams: 1 arquivototal.pdf: 1170942 bytes, checksum: b6572bc762a0d2c24c5e7ff182b558fb (MD5) / Made available in DSpace on 2015-11-23T13:12:31Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1170942 bytes, checksum: b6572bc762a0d2c24c5e7ff182b558fb (MD5) Previous issue date: 2015-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This research is developed from two categories dear to Bakhtinian thought, dialogue and ethics, and seeks to delimit some philosophical assumptions underlying the Bakhtinian theory of language. We therefore provide an analytical reading of the essay written approximately between the years 1920 to 1924, whose text, considered a fragment, has the following title: For a Philosophy of the Responsible Act (hereafter referred to in this paper as PFAR) by Mikhail Mikhailovich Bakhtin (1895-1975). The corpus chosen, whose hermetic nature is unfinished, imposes difficulties and motivates this work, which covers two moments: reading as a documental research and the interpretative analysis of the passages in the light of the methodological theory, which makes it possible to find philosophical assumptions in the Bakhtinian Theory of Language. In this way, one can clarify the constitutive heterogeneity by Authier-Revuz (1982, 1990, 1998, 2004, and 2007) and of the voices in the Bakhtinian text, given that not always do these appear in an explicit form when the categories, ethics and dialogism, are developed. From this author we work, especially, with the concepts of shown and constituted heterogeneity, in an approach that requires of the author a positioning and a justification for the reasons that result in his choices. In this way, this task is beyond the identification of discursive heterogeneity. The intention, here, is to characterize Kierkegaard ([1844] 2010) and Buber ([1923] 2001) as the presumed philosophers in Bakhtin ([1920-24] 2010). These theories are important: Ponzio (2010), Faraco (2010a), Tezza (2003) e Sobral (2005a, 2005b, 2009, 2010). With this in mind, specific procedures are necessary, which provide the systematic analysis and the interpretation of the data. In this way, the methodology has an exploratory character and an interpretative stamp. It remains to be seen if the Bakhinian conception of ethics and of dialogism presents discursive heterogeneity with the thoughts of Kierkegaard ([1844] 2010) and Buber ([1923] 2001) are consist of the trademarks of constitutive heterogeneity of language, respectively. / O objetivo geral desta pesquisa é analisar as marcas de heterogeneidade constitutiva por meio de duas categorias da Filosofia Bakhtiniana da Linguagem, a saber, diálogo e ética. Estas se sobressaíram do ensaio Para uma filosofia do ato responsável. Escrito do jovem Mikhail Mikhailovich Bakhtin (1895-1975) que constitui o corpus desta tese. Embora tenha sido publicado pela primeira vez em russo, no ano 1986, com o título K filosofii postupok, foi escrito por volta de 1920 e 1924. Constituem os objetivos específicos: a) apresentar o contexto histórico e social referentes ao corpus, b) Traçar o caminho metodológico da análise, c) expor os conceitos de ética e diálogo, d) destacar as marcas de heterogeneidade constitutiva, e) discutir o diálogo heterogeneamente constitutivo de Bakhtin ([1920-1924] 2010) com os filósofos Kierkegaard ([1844] 2010), no tocante à ética e Buber ([1923] 2001), no que diz respeito ao diálogo. Principalmente Bakhtin ([1920-1924] 2010) e os estudiosos Ponzio (2010), Faraco (2010a), Tezza (2003) e Sobral (2005a, 2005b, 2009, 2010) são os teóricos que respaldam esta pesquisa. O aporte teórico-metodológico segue a abordagem da Teoria da Enunciação da linguista francesa Authier-Revuz (1982, 1990, 1998, 2004, 2007), eixo teórico-metodológico que possibilita realizar este empreendimento. Em consonância com esta proposta, pautamo-nos no conceito da heterogeneidade constitutiva, porque acreditamos que este trabalho vai mais além do ato investigar os pressupostos filosóficos na Filosofia Bakhtiniana da Linguagem. Para tanto, esta é uma investigação, de caráter exploratório e de natureza qualitativa cujos procedimentos metodológicos abrangem dois momentos: pesquisa documental e análise interpretativista. Desse modo, é imperativo perguntar: quem são os filósofos que Bakhtin ([1920-1924] 2010) convidou para dialogar sobre a ética e o diálogo, enquanto assuntos específicos para a sua Filosofia da Linguagem? Partimos, portanto, da seguinte hipótese: as marcas de heterogeneidade constitutiva no corpus analisado encontram-se nas categorias, ética e diálogo, a partir de dois pensadores, a saber, o dinamarquês Søren Aabye Kierkegaard (1813-1855) e o austríaco Martin Buber (1878-1965), respectivamente.