8 documents found, page 1 of 1
Thermodynamic stacking fault energy, chemical composition, and microstructure r...
Ribamar, Giovani Gonçalves; Andrade, Tathiane Caminha; Miranda, Hélio Cordeiro de; Abreu, Hamilton Ferreira Gomes deStacking fault energy (SFE) is related to activating complex high strength and ductility mechanisms such as transformation-induced plasticity and twinning-induced plasticity effects. This type of energy can be estimated by many different methods and its importance is in its ability to predict microstructure and phase transformation behavior when the material is submitted to stress/strain. In order to study the ...
Study of the relationship between stacking fault energy and microstructure in d...
Ribamar, Giovani Gonçalves; Andrade, Tathiane Caminha; Miranda, Hélio Cordeiro de; Abreu, Hamilton Ferreira Gomes deThe properties of high manganese steels are usually related to the mechanism of austenite deformation, either martensite or twin formation during deformation. This deformation mechanism is often related to the stacking fault energy (SFE) that the material possesses. Studies show that SFE values between 0 and 8 mJ/m² provide formation of ε martensite during deformation, whereas only twins are formed for energies...
Direct Observation of Austenite Reversion During Aging of 18Ni (350 Grade) Mara...
Feitosa, Ana Larissa Melo; Escobar, Julián; Ribamar, Giovani Gonçalves; Avila, Julian Arnaldo [UNESP]; Padilha, Angelo FernandoMade available in DSpace on 2022-04-28T19:47:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-02-01; Austenite reversion in Fe–Ni alloys plays a significant role in determining their mechanical properties. Increasing the austenite content in these alloys improves their toughness but reduces their mechanical strength. In this work, austenite-reversion heat treatments between 600 °C and 700 °C were studi...
Análise da microestrutura e das propriedades mecânicas do vergalhão CA-50 em di...
Feitosa, Ana Larissa Melo; Almeida, Emmanuel de Sousa; Ribamar, Giovani Gonçalves; Silva, Marcelo José Gomes daDue the fast growth of civil construction and the high consumption of metal products in this area, more and more are sought in these materials, properties that meet the diverse needs of market. The microstructural knowledge of these materials and your microstructural manipulation by use of heat treatment, it is extremely important to ensure safety in the development of new buildings. To analyze and understand t...
Caracterização microestrutural da fase sigma no aço inoxidável superaustenítico...
Silva, Maria do Socorro da; Ribamar, Giovani Gonçalves; Feitosa, Ana Larissa Melo; Silva, Marcelo José Gomes daStainless steels are mainly characterized by high corrosion resistance in various environments. This characteristic comes from the formation of a cromium oxide film, requiring at least 11%wt Cr. The superaustenitic stainless steel class is derived from austenitic stainless steel by the addition of alloying elements. The work environment temperature can favour precipitate formation that can affect the mechanical...
Caracterização de ligas Fe-Ni processadas por metalurgia do pó: influência dos ...
Ribamar, Giovani Gonçalves; Lobo, Cândido Jorge de Sousa; Silva, Marcelo José Gomes daPowder metallurgy becomes an important process for obtaining pieces with complex geometry, making them increasingly viable. The aim of this work is to characterize and evaluate the influence of mixing energy and mixing time on the microstructure and mechanical properties (hardness) of the alloy Fe 70% - 30% Ni, used in electronics and structural materials of automotive engine parts, being produced by powder met...
Estudo da relação entre a composição química, energia de falha de empilhamento ...
Ribamar, Giovani GonçalvesSteels with high manganese content have been gaining more prominence due to their high toughness in cryogenic environments and excellent allied resistance and high ductility. These materials have a structure composed of austenitic matrix, and may present ferrite, α’ martensite and ε martensite, depending on the content of the alloying elements. The properties of these materials are often related to the mechanis...
Caracterização da liga Ti-64 produzida pelo processo direct metal laser sinteri...
Ribamar, Giovani GonçalvesRIBAMAR, Giovani Gonçalves Ribamar. Caracterização da liga Ti-64 produzida pelo processo direct metal laser sintering (DMLS) e estudo comparativo com outros processos de fabricação. 2016. 47 f. Monografia (Graduação em Engenharia Metalúrgica)-Universidade Federal do Ceará, Fortaleza, 2016.; Throughout the years, many material production techniques have been developed with the objective of improving the properti...