Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-07-22T14:09:55Z No. of bitstreams: 1 472531 - Texto Completo.pdf: 4997837 bytes, checksum: 1590f79ac735e6692cd0c7dd643ff084 (MD5) / Made available in DSpace on 2015-07-22T14:09:55Z (GMT). No. of bitstreams: 1 472531 - Texto Completo.pdf: 4997837 bytes, checksum: 1590f79ac735e6692cd0c7dd643ff084 (MD5) Previous issue date: 2015-03-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The present study aims to evaluate the wear resistance of two different materials (SAE 1045 steels and SAE 52100) in different microstructure conditions without lubrification and using biodiesel (B100), biodiesel-diesel blend (B50) and commercial diesel fuel (B7). Two samples of each material were subjected to hardening heat treatment of quenching (temperature: 850 ?C and cooled in water in SAE 1045 samples and temperature: 830?C cooled in oil in SAE 52100 steel samples) followed by tempering (300?C in samples of SAE 1045 steel and 100?C and 200?C in SAE 52100 steel samples to 100 ? C). It was obtained samples with four different hardness and different microstructure conditions (tempered martensite in steel SAE 1045 and tempered martensite with Chromium Carbide in steel SAE 52100). The experiments will be conducted in a pin-on-disk tribometer, with rotation of 300 RPM, 1,5kg load and 4400 m distance covered, according to the recommendations of ASTM G99-04, followed by the wear track surface hardness measurement and evolution of the samples wear surface with a Scanning Electron Microscope. At the end of the trials, there was a variation of wear resistance between different materials, different microstructures and different lubricants applied in the test. The results showed a tendency to decrease in wear tests with B100 biodiesel lubrication. / O presente trabalho tem por objetivo avaliar a resist?ncia ao desgaste de dois diferentes materiais (tr?s amostras de SAE 1045 e tr?s amostras de a?o SAE 52100) em diferentes condi??es microestruturais, sem lubrifica??o e com lubrifica??o (utilizando biodiesel B100, ?leo diesel B50 e ?leo diesel comercial B7). Duas amostras de cada material foram submetidas a tratamento t?rmico de t?mpera (850?C resfriado em ?gua nas amostras de SAE 1045 e 830?C resfriado em ?leo nas amostras de a?o SAE 52100) seguida de revenimento (100?C e 300?C nas amostras de SAE 1045 e 100?C e 200?C nas amostras de a?o SAE 52100). Assim, foram obtidas amostras com quatro durezas diferentes e diferentes condi??es microestruturais (martensita revenida no a?o SAE 1045 e martensita revenida com uma terceira fase prioritariamente de carbeto de cromo no a?o SAE 52100). Os ensaios foram realizados em um trib?metro do tipo pino-sobre-disco, com rota??o de 300 RPM, 1,5kg de carga e 4400m de dist?ncia percorrida, seguindo as recomenda??es da norma ASTM G99?04, medi??o da microdureza superficial da pista de desgaste e avalia??o da superf?cie desgastada das amostras com um Microsc?pio Eletr?nico de Varredura (MEV). Ao final dos ensaios, observou-se a varia??o da resist?ncia ao desgaste entre os diferentes materiais, diferentes microestruturas e diferentes lubrificantes aplicados no ensaio. Os resultados indicaram uma tend?ncia de diminui??o de desgaste nos ensaios realizados com lubrifica??o de biodiesel B100.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-02T12:02:52Z No. of bitstreams: 1 OtoLimaDeAlbuquerqueNeto_DISSERT.pdf: 2860370 bytes, checksum: a36d92183fffc74b8e6ee04835f7be2c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-07T16:02:51Z (GMT) No. of bitstreams: 1 OtoLimaDeAlbuquerqueNeto_DISSERT.pdf: 2860370 bytes, checksum: a36d92183fffc74b8e6ee04835f7be2c (MD5) / Made available in DSpace on 2017-02-07T16:02:51Z (GMT). No. of bitstreams: 1 OtoLimaDeAlbuquerqueNeto_DISSERT.pdf: 2860370 bytes, checksum: a36d92183fffc74b8e6ee04835f7be2c (MD5) Previous issue date: 2016-08-02 / Os ?leos lubrificantes geralmente s?o produzidos a partir de fontes n?o renov?veis, como por exemplo o petr?leo. Estes lubrificantes possuem aditivos para que suas propriedades sejam melhoradas e adequadas para aplica??es espec?ficas o que eleva o custo de produ??o al?m do elevado poder de degrada??o ambiental devido ao seu descarte incorreto. Como forma de reduzir os impactos ambientais e elevado custo de produ??o dos ?leos lubrificantes, foram desenvolvidos estudos voltados para os biolubrificantes originados de oleaginosas que possuem grande potencial de produ??o no territ?rio brasileiro, al?m da redu??o do impacto ambiental por ser um ?leo biodegrad?vel. A lubrifica??o apresenta uma grande import?ncia para o setor industrial, pois contribui para o aumento do ciclo de vida dos componentes mec?nicos de equipamentos de m?dio e grande porte reduzindo o desgaste excessivo entre pe?as com movimento relativo entre si e a refrigera??o dos componentes. O ?leo vegetal produzido a partir do fruto da planta oiticica (Licania r?gida) da familia Chrysobalanaceae, encontrada nas vegeta??es da caatinga, surge como alternativa para uso como biolubrificante devido ao seu baixo custo e f?cil extra??o. No presente trabalho, foram utilizados os m?todos de extra??o mec?nica e qu?mica, para posterior an?lise f?sico-qu?mica e demais par?metros operacionais que devem existir para o bom funcionamento de um ?leo lubrificante. Verificou-se que o m?todo de extra??o mec?nica se mostrou mais eficaz quanto a rapidez da produ??o, mas a extra??o qu?mica mostrou um maior rendimento em rela??o a massa do vegetal e o volume produzido do ?leo. Os valores das propriedades f?sico-qu?micas do ?leo da oiticica para ambas as extra??es se apresentaram similares, logo ambos os m?todos podem ser utilizados para a obten??o do ?leo da oiticica sem se preocupar com altera??es significativas nas principais propriedades esperadas por um ?leo lubrificante vegetal. Os ensaios de desempenho quanto a condutividade e resistividade t?rmica apresentaram valores superiores em compara??o ao ?leo comercial, provando assim que o ?leo vegetal possui uma melhor capacidade de refrigera??o em rela??o ao ?leo comercial. A an?lise de desgaste provou que o poder de lubrifica??o do ?leo da oiticica foi superior em rela??o ao ?leo comercial. / Lubricating oils are usually produced from non-renewable resources such as petroleum. These lubricants have additives that their properties are improved and suitable for specific applications which increases the production cost of high power of environmental degradation due to its incorrect disposal. In order to reduce environmental impacts and high cost of production of lubricating oils, studies were developed focused on the bio-lubricants derived from oil which have large production potential in Brazil, in addition to reducing the environmental impact by being a biodegradable oil. Lubrication is of great importance for the industrial sector, it contributes to increase the life cycle of the mechanical components of medium and large equipment reducing excessive wear between parts with relative movement between itself and the cooling of the components. The vegetable oil produced from the fruit of the myrtle plant (rigid Licania) of Chrysobalanaceae family, found in the caatinga vegetation, is an alternative for use as biolubrificante due to its low cost and easy extraction. In this work, methods of mechanical and chemical extraction were used for subsequent physical and chemical analysis and other operating parameters that must exist for the proper functioning of a lubricating oil. It was observed that the mechanical extraction method was more effective as the speed of production, but the chemical extraction showed a higher yield compared to vegetable mass and volume of produced oil. The values of the physico-chemical properties oiticica oil for both extractions performed similar, then both methods can be used to obtain oiticica oil without worrying about significant changes in key properties expected for vegetable lubricating oil. The performance tests as conductivity and thermal resistivity showed higher values in comparison with the commercial oil, thus proving that the vegetable oil has an improved cooling capacity compared to the commercial oil. The wear analysis proved that the power of oiticica oil lubrication was higher than the commercial oil.