Tecnologia em Metalurgia Materiais e Mineracao最新文献

{"title":"Caracterização microestrutural da camada de NiCrAlY sobre Ti-6Al-4V processado por laser de Yb:fibra","authors":"Renata Jesuina Takahashi, João Marcos Kruszynski de Assis, Rudimar Riva, Aline Capella de Oliveira, Danieli Aparecida Pereira Reis","doi":"10.4322/2176-1523.20222776","DOIUrl":"https://doi.org/10.4322/2176-1523.20222776","url":null,"abstract":"","PeriodicalId":53327,"journal":{"name":"Tecnologia em Metalurgia Materiais e Mineracao","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70527574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial: Wilson Luiz Guesser (1952-2020)","authors":"Giuseppe Pintaude, André Silva","doi":"10.4322/2176-1523.202219spe01","DOIUrl":"https://doi.org/10.4322/2176-1523.202219spe01","url":null,"abstract":"","PeriodicalId":53327,"journal":{"name":"Tecnologia em Metalurgia Materiais e Mineracao","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70525792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influência da variação de temperatura nos aspectos microestruturais e propriedades mecânicas no bronze de alumínio-níquel UNS C63000 submetido ao processo de têmpera","authors":"Vinícius Torres dos Santos, M. Silva, Huang Han Pang, F. Lobo, G. Santos, Wilson Carlos da Silva Junior, A. Couto","doi":"10.4322/2176-1523.20212507","DOIUrl":"https://doi.org/10.4322/2176-1523.20212507","url":null,"abstract":"","PeriodicalId":53327,"journal":{"name":"Tecnologia em Metalurgia Materiais e Mineracao","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70526031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Obtenção de superfície porosa e condutora em aço inoxidável ferrítico","authors":"P. Leite, César Eduardo Schimitt, Fernando Dal Pont Morisso, C. Carone, Sandra Raquel Kunst, Jane Zoppas Ferreira, C. T. Oliveira","doi":"10.4322/2176-1523.20222183","DOIUrl":"https://doi.org/10.4322/2176-1523.20222183","url":null,"abstract":"","PeriodicalId":53327,"journal":{"name":"Tecnologia em Metalurgia Materiais e Mineracao","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70526312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Avaliação de risco dos rejeitos da usina desativada de flotação de galena e esfalerita da Mineração Boquira (Bahia, Brasil)","authors":"L. Souza, Luiz Rogério Pinho de Andrade Lima","doi":"10.4322/2176-1523.20222570","DOIUrl":"https://doi.org/10.4322/2176-1523.20222570","url":null,"abstract":"","PeriodicalId":53327,"journal":{"name":"Tecnologia em Metalurgia Materiais e Mineracao","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70526602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ensaio de corrosão acelerado para avaliação do metal formador de tanques de armazenagem de biodiesel","authors":"Renan Francisco Bohrer Klein, Leonardo Felix Scheffel, C. Carone, Fernando Dal Pont Morisso, Sandra Raquel Kunst, Jane Zoppas Ferreira, C. T. Oliveira, Luciane Taís Fuhr","doi":"10.4322/2176-1523.20222102","DOIUrl":"https://doi.org/10.4322/2176-1523.20222102","url":null,"abstract":"With progress in biodiesel driven by renewable energy matrices, Brazil is at the forefront of using vegetable and animal oil as the automotive fuel. The dynamic production of biodiesel solutions for the production of biodiesel, since the industry in general uses metallic tanks for the development of other fuels with different physical and chemical characteristics. Industrial corrosion is a 30% industry results from installation with subsequent replacement or preventive maintenance. The work sought a methodology to evaluate the corrosion of steel from tanks used for the storage of biodiesel, due to the absence of a specific methodology for the analysis of biodiesel as a corrosion factor. Tests of cloudiness with biodiesel were developed in an experimental machine, as well as immersion tests and electrochemical tests for comparison. A statistical basis for experiment planning was performed. The results were more aggressive than the specified steel, and what is present in the fuel is the factor that has the greatest impact on corrosion.","PeriodicalId":53327,"journal":{"name":"Tecnologia em Metalurgia Materiais e Mineracao","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70525896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermomechanical fatigue behavior of CGI 450 and CGI 500 cast irons","authors":"Márcio Henrique Ferreira, D. Bon, W. W. Bose, C. Cabezas, W. L. Guesser","doi":"10.4322/2176-1523.20222640","DOIUrl":"https://doi.org/10.4322/2176-1523.20222640","url":null,"abstract":"The vermicular cast iron grade 450 is widely used in engineering applications, primarily by the automotive industry in the fabrication of internal combustion engines. However, in recent years, the vermicular cast iron grade 500 has been developed, and new studies searching for the replacement of the grade 450, with the aim of increasing the high-performance internal combustion engines life, as well as reducing their weight, are in development. Due to their operational characteristics, these engines are subjected simultaneously to thermal and mechanical cycles, which influence their useful life. Therefore, the characterization of the resistance to these types of loads for materials selection for these engines, is very important. Thus, the objective of this work was to study the thermomechanical fatigue life of two vermicular cast irons in conditions close to those to which internal combustion engines are subjected. The materials were characterized by chemical and metallographic analyses and tensile tests. The thermomechanical fatigue tests were carried out at temperatures ranging from 50 ºC to 420 ºC, and a dwell time of 180 seconds. The vermicular cast iron grade 500 exhibited higher tensile strength, with higher ductility when compared to the grade 450, as well as higher fatigue strength. These properties were related to the size and distribution of eutectic cells (graphite) in the matrix.","PeriodicalId":53327,"journal":{"name":"Tecnologia em Metalurgia Materiais e Mineracao","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70526618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurements of hardness, young s modulus, and fracture toughness of solar grade silicon obtained from metallurgical grade silicon","authors":"Denir Paganini Nascimento, M. Martorano, Caio Cesar Cebalos de Almeida, A. F. Padilha","doi":"10.4322/2176-1523.20222726","DOIUrl":"https://doi.org/10.4322/2176-1523.20222726","url":null,"abstract":"Young modulus and toughness (K IC ) of bulk solar grade silicon (SoG-Si) obtained by directional solidification of metallurgical grade silicon were determined. The Young modulus was measured by the technique of impulse excitation of vibration and K IC was determined using the indentation method. Measurement values agree well with those available in the literature. The indentation method proved to be a reliable, relatively simple, inexpensive, and fast experimental method to measure K IC in SoG-Si.","PeriodicalId":53327,"journal":{"name":"Tecnologia em Metalurgia Materiais e Mineracao","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70526646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Si content on the machinability of ductile iron","authors":"Tiago Silvério Guimarães Xavier, L. R. R. Silva, W. Guesser, Á. R. Machado","doi":"10.4322/2176-1523.20222668","DOIUrl":"https://doi.org/10.4322/2176-1523.20222668","url":null,"abstract":"The development of new chemical compositions of cast iron contributes to increasing the competitiveness of foundry and manufacturing companies that always seek to optimize the properties of these materials. Previous works detected machinability variation along the cross-section of nodular cast irons (DI) bars produced by continuous casting due to the variation of the microstructure and mechanical properties presented, with decreasing machinability from the periphery to the core. This variation imposes complications, as it implies different ideal (or optimal) cutting conditions along the cross-section of the round bars. Assays with ductile irons (DI) with varying silicon content showed that the reduction in silicon decreased the microhardness of ferrite and increased the percentage of pearlite in the matrix, thus generating a decrease in the ductility of the material. Thus, this work investigates the effect of silicon content on machinability variation along the cross-section of nodular cast iron bars in the turning process. Three different types of nodular cast iron alloys were used, differing by the amount of silicon in the composition. Material characterization and machining tests were carried out in three regions: the periphery, the intermediate region, and the core. The hardness, metallography, size of graphite nodules, and amount per region were analyzed in the characterization tests and compared to the evolution of wear and tool life machining force and surface roughness. The addition of different percentages of silicon did not avoid the differences in behavior between the three regions of the same material, but it changed the behavior of the three alloys studied. The silicon content affects the material’s microstructure, which, together with the cooling rate, favors the differentiation of graphite nodules in different sizes, arrangements, and spacing. This differentiation contributes to the difference in the material’s behavior in the machining between the regions along the cross-section. Strengthening in the core region was a trend in all three alloys. There was a statistical difference in roughness between the regions of the material. Cast iron with medium silicon content showed lower machining force and roughness values but close to those of high silicon. As with high-silicon cast iron, the forces remained at a more stabilized level, without significant variations between regions of the material.","PeriodicalId":53327,"journal":{"name":"Tecnologia em Metalurgia Materiais e Mineracao","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70526841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methodology to include the comminution specific energy into open-pit strategy mine planning using global optimization","authors":"J. Mata, Alizeibek Saleimen Nader, D. Mazzinghy","doi":"10.4322/2176-1523.20222752","DOIUrl":"https://doi.org/10.4322/2176-1523.20222752","url":null,"abstract":"Strategic Mine Planning demands an accurate knowledge of the mineral deposit, being very important the use of block models supported by Geometallurgy. Currently, the methodology used considers the mine planning divided into parts (ultimate open pit, pushbacks, scheduling). Global optimization can guarantee the optimal solution once all steps are solved together. In the present study the database Marvin was used and the geometallurgical variable comminution specific energy was included. In the first scenario, called GeoMet1, a ramp-up was included in the first three years. In the GeoMet2, different maximum movement ranges were defined, as well as the implementation of ore stockpiles and their subsequent rehandling. Gains of 9.66% in NPV and 5.18% in ore production were found for GeoMet2. The second scenario presented ore production adhering to the programmed, in addition to greater stability in the stripping ratio. In addition, GeoMet2 was more efficient in controlling the comminution specific energy. Therefore, the implementation of mass movement limitations allied to the use of stockpiles favored the optimization of the mine scheduling results. It was possible to verify the importance of including the variable comminution specific energy in the block model, to provide more realistic and reliable results.","PeriodicalId":53327,"journal":{"name":"Tecnologia em Metalurgia Materiais e Mineracao","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70527241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}