Este é um artigo publicado em acesso aberto (Open Access) sob a licença Creative Commons Attribut... more Este é um artigo publicado em acesso aberto (Open Access) sob a licença Creative Commons Attribution Non-Commercial, que permite uso, distribuição e reprodução em qualquer meio, sem restrições desde que sem fins comerciais e que o trabalho original seja corretamente citado.
Like any other new technology there are lots of constraints and limitations to augmented reality ... more Like any other new technology there are lots of constraints and limitations to augmented reality that need to be considered when designing the user experience. The purpose of this article is to report the user experience of AR technology in welding education for future studies and applications. AR technology of the welding process consists of indirect vision of welding helmet, called HMDs (Head Mounted Displays) coupled with the welding torch and the portable device containing peripherals and software for the simulation of welding source, positioning system and plate with the material base. The Welding simulation training was conducted for a group of 12 students of Welding discipline of Mechanical Engineering course at the Federal University of Paraná. The equipment used to conduct the study was the Soldamatic, in which we performed the welding simulations in embedded plates with augmented reality and software called "Teacher". The simulator is equipped with a mask similar and SMAW (Shielded Metal Arc Welding) identical used in the actual welding torches MIG / MAG and TIG in real situations. The results of this study can help the teacher with relevant parameters for the organization of training, as it guides as in the present case study, the need to insert a phase perception of pre-training in AR. It also suggests further studies in order to compare the performance index of learning in simulated welding environment when associated with a previous training perception of AR.
Efeito da temperatura interpasse na microestrutura, tenacidade ao impacto e propagação de trinca ... more Efeito da temperatura interpasse na microestrutura, tenacidade ao impacto e propagação de trinca por fadiga de uniões soldadas por GTAW do aço ASTM A743-CA6NM (Interpass temperature influence on the microstructure, impact toughness and fatigue crack propagation in ASTM A743-CA6NM GTAW welded joints)
Análise do desgaste de capas de eletrodos de solda ponto e sua influência na qualidade da soldage... more Análise do desgaste de capas de eletrodos de solda ponto e sua influência na qualidade da soldagem de chapas automotivas galvanizadas (Assessment of spot welding electrodes wearing and their influence on the quality of welded automotive galvanized sheets)
ABSTRACT Mainly due to their great toughness, martensitic stainless steels are used for manufactu... more ABSTRACT Mainly due to their great toughness, martensitic stainless steels are used for manufacturing hydraulic turbines. However, these steels have some restrictions regarding regions recovered by welding, mainly due to the formation of non-quenched martensite, which causes a reduction in toughness. Considering repair of hydraulic turbines, there is a great interest in developing welding procedures that increase impact toughness and avoid post-welding heat treatment (TTPS). This study aims to analyse the influence of interpass temperature on microstructure, impact toughness and fatigue crack propagation in multipass welded joints on martensitic stainless steel CA6NM, using AWS410NiMo filler metal and the gas tungsten arc welding (GTAW) process. In the sample with interpass temperature of 80°C, influence of the interpass temperature on the formation of ferrite δ, with intragranular formation in the two-phase δ field, was observed, while in the sample welded at 150°C, the formation of ferrite δδ occurred mainly in the single-phase field. The change in the formation of ferrite δ, with the low interpass temperature, promoted an increase in impact toughness and a decrease in the fatigue crack propagation when compared with the sample welded with a higher interpass temperature. The results obtained indicate that the TIG process is an excellent alternative for the repair of CA6NM steel, with a significant influence from the interpass temperature.
Like any other new technology there are lots of constraints and limitations to augmented reality ... more Like any other new technology there are lots of constraints and limitations to augmented reality that need to be considered when designing the user experience. The purpose of this article is to report the user experience of AR technology in welding education for future studies and applications. AR technology of the welding process consists of indirect vision of welding helmet, called HMDs (Head Mounted Displays) coupled with the welding torch and the portable device containing peripherals and software for the simulation of welding source, positioning system and plate with the material base. The Welding simulation training was conducted for a group of 12 students of Welding discipline of Mechanical Engineering course at the Federal University of Paraná. The equipment used to conduct the study was the Soldamatic, in which we performed the welding simulations in embedded plates with augmented reality and software called "Teacher". The simulator is equipped with a mask similar and SMAW (Shielded Metal Arc Welding) identical used in the actual welding torches MIG / MAG and TIG in real situations. The results of this study can help the teacher with relevant parameters for the organization of training, as it guides as in the present case study, the need to insert a phase perception of pre-training in AR. It also suggests further studies in order to compare the performance index of learning in simulated welding environment when associated with a previous training perception of AR.
Tese (Doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico.Estudou-se a brasag... more Tese (Doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico.Estudou-se a brasagem sem fluxo entre aço carbono e cobre buscando avaliar a influência dos materiais base, dos metais de adição, das atmosferas de brasagem e do ciclo térmico na qualidade final da junta brasada. As brasagens foram realizadas utilizando metais de adição convencionais contendo Ag-Cu, Ag-Cu-Sn e Ag-Cu-Zn-Sn na forma de arame, ou através de revestimento de Sn, pela técnica conhecida como união por fase líquida transiente. Alto vácuo, médio vácuo, nitrogênio e mistura argônio-hidrogênio serviram como atmosferas de brasagem. A qualidade da junta brasada com metais de adição convencionais pode ser avaliada pela presença de defeitos, tais como pequenos rechupes, falhas de enchimento e até mesmo a presença de trincas. A ocorrência destes defeitos depende da combinação metal de adição/atmosfera de brasagem e da temperatura de brasagem utilizadas. O alto vácuo mostrou-se como a melhor atmosfera de b...
ABSTRACT O objetivo deste trabalho foi estudar a influência da corrente de soldagem sobre o rendi... more ABSTRACT O objetivo deste trabalho foi estudar a influência da corrente de soldagem sobre o rendimento bruto de fusão em soldagem MIG/MAG, levando-se em consideração as dimensões da peça. Para isto, foram feitas soldagens sobre chapas de três espessuras em uma faixa de corrente, utilizando-se o processo MIG/MAG CMT com o auxílio de uma unidade robótica. A escolha desse processo se deu para minimizar o efeito mecânico do arco no rendimento bruto de fusão, fato experimentalmente comprovado no trabalho. Foi verificado que o aumento da corrente e/ou redução da combinação espessura-largura da chapa fazem aumentar o rendimento bruto de fusão. Mas a intensidade do efeito da corrente depende da combinação espessura-largura da chapa. Abstract: The objective of the present paper was to study the influence of the welding current on the gross fusion efficiency in MIG/MAG welding, taking into account the plate dimensions. A series of weldments were carried out over three thickness plates in a current range utilizing the MIG/MAG CMT process, aided by a robotic unity. The choice of the process aimed to minimize the arc mechanical effect on the gross fusion efficiency, fact experimentally checked in the work. It was verified that an increase of current and/or reduction in the thickness-width combination leads to higher gross fusion efficiency. However, the intensity of the current effect depends on the thickness-width combination
ABSTRACT Mainly due to their great toughness, martensitic stainless steels are used for manufactu... more ABSTRACT Mainly due to their great toughness, martensitic stainless steels are used for manufacturing hydraulic turbines. However, these steels have some restrictions regarding regions recovered by welding, mainly due to the formation of non-quenched martensite, which causes a reduction in toughness. Considering repair of hydraulic turbines, there is a great interest in developing welding procedures that increase impact toughness and avoid post-welding heat treatment (TTPS). This study aims to analyse the influence of interpass temperature on microstructure, impact toughness and fatigue crack propagation in multipass welded joints on martensitic stainless steel CA6NM, using AWS410NiMo filler metal and the gas tungsten arc welding (GTAW) process. In the sample with interpass temperature of 80°C, influence of the interpass temperature on the formation of ferrite δ, with intragranular formation in the two-phase δ field, was observed, while in the sample welded at 150°C, the formation of ferrite δδ occurred mainly in the single-phase field. The change in the formation of ferrite δ, with the low interpass temperature, promoted an increase in impact toughness and a decrease in the fatigue crack propagation when compared with the sample welded with a higher interpass temperature. The results obtained indicate that the TIG process is an excellent alternative for the repair of CA6NM steel, with a significant influence from the interpass temperature.
As capas de eletrodos utilizados na soldagem por resistência por pontos (solda ponto) sofrem desg... more As capas de eletrodos utilizados na soldagem por resistência por pontos (solda ponto) sofrem desgaste durante a soldagem de chapas galvanizadas, devido ao elevado aquecimento e pressão na sua superfície. Neste trabalho avaliou-se a influência do desgaste sofrido por diferentes tipos de capas de eletrodos sobre as propriedades mecânicas e acabamento do ponto de solda. Observou-se que o desgaste varia de acordo com a capacidade de retenção de dureza a quente, e que a superfície das capas sofre intensa reação com o zinco da chapa galvanizada. Como conseqüência do desgaste das capas de eletrodo, o ponto de solda sofre redução progressiva do seu diâmetro (o que pode comprometer sua integridade estrutural), além de uma piora significativa do seu acabamento superficial.
Este é um artigo publicado em acesso aberto (Open Access) sob a licença Creative Commons Attribut... more Este é um artigo publicado em acesso aberto (Open Access) sob a licença Creative Commons Attribution Non-Commercial, que permite uso, distribuição e reprodução em qualquer meio, sem restrições desde que sem fins comerciais e que o trabalho original seja corretamente citado.
Like any other new technology there are lots of constraints and limitations to augmented reality ... more Like any other new technology there are lots of constraints and limitations to augmented reality that need to be considered when designing the user experience. The purpose of this article is to report the user experience of AR technology in welding education for future studies and applications. AR technology of the welding process consists of indirect vision of welding helmet, called HMDs (Head Mounted Displays) coupled with the welding torch and the portable device containing peripherals and software for the simulation of welding source, positioning system and plate with the material base. The Welding simulation training was conducted for a group of 12 students of Welding discipline of Mechanical Engineering course at the Federal University of Paraná. The equipment used to conduct the study was the Soldamatic, in which we performed the welding simulations in embedded plates with augmented reality and software called "Teacher". The simulator is equipped with a mask similar and SMAW (Shielded Metal Arc Welding) identical used in the actual welding torches MIG / MAG and TIG in real situations. The results of this study can help the teacher with relevant parameters for the organization of training, as it guides as in the present case study, the need to insert a phase perception of pre-training in AR. It also suggests further studies in order to compare the performance index of learning in simulated welding environment when associated with a previous training perception of AR.
Efeito da temperatura interpasse na microestrutura, tenacidade ao impacto e propagação de trinca ... more Efeito da temperatura interpasse na microestrutura, tenacidade ao impacto e propagação de trinca por fadiga de uniões soldadas por GTAW do aço ASTM A743-CA6NM (Interpass temperature influence on the microstructure, impact toughness and fatigue crack propagation in ASTM A743-CA6NM GTAW welded joints)
Análise do desgaste de capas de eletrodos de solda ponto e sua influência na qualidade da soldage... more Análise do desgaste de capas de eletrodos de solda ponto e sua influência na qualidade da soldagem de chapas automotivas galvanizadas (Assessment of spot welding electrodes wearing and their influence on the quality of welded automotive galvanized sheets)
ABSTRACT Mainly due to their great toughness, martensitic stainless steels are used for manufactu... more ABSTRACT Mainly due to their great toughness, martensitic stainless steels are used for manufacturing hydraulic turbines. However, these steels have some restrictions regarding regions recovered by welding, mainly due to the formation of non-quenched martensite, which causes a reduction in toughness. Considering repair of hydraulic turbines, there is a great interest in developing welding procedures that increase impact toughness and avoid post-welding heat treatment (TTPS). This study aims to analyse the influence of interpass temperature on microstructure, impact toughness and fatigue crack propagation in multipass welded joints on martensitic stainless steel CA6NM, using AWS410NiMo filler metal and the gas tungsten arc welding (GTAW) process. In the sample with interpass temperature of 80°C, influence of the interpass temperature on the formation of ferrite δ, with intragranular formation in the two-phase δ field, was observed, while in the sample welded at 150°C, the formation of ferrite δδ occurred mainly in the single-phase field. The change in the formation of ferrite δ, with the low interpass temperature, promoted an increase in impact toughness and a decrease in the fatigue crack propagation when compared with the sample welded with a higher interpass temperature. The results obtained indicate that the TIG process is an excellent alternative for the repair of CA6NM steel, with a significant influence from the interpass temperature.
Like any other new technology there are lots of constraints and limitations to augmented reality ... more Like any other new technology there are lots of constraints and limitations to augmented reality that need to be considered when designing the user experience. The purpose of this article is to report the user experience of AR technology in welding education for future studies and applications. AR technology of the welding process consists of indirect vision of welding helmet, called HMDs (Head Mounted Displays) coupled with the welding torch and the portable device containing peripherals and software for the simulation of welding source, positioning system and plate with the material base. The Welding simulation training was conducted for a group of 12 students of Welding discipline of Mechanical Engineering course at the Federal University of Paraná. The equipment used to conduct the study was the Soldamatic, in which we performed the welding simulations in embedded plates with augmented reality and software called "Teacher". The simulator is equipped with a mask similar and SMAW (Shielded Metal Arc Welding) identical used in the actual welding torches MIG / MAG and TIG in real situations. The results of this study can help the teacher with relevant parameters for the organization of training, as it guides as in the present case study, the need to insert a phase perception of pre-training in AR. It also suggests further studies in order to compare the performance index of learning in simulated welding environment when associated with a previous training perception of AR.
Tese (Doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico.Estudou-se a brasag... more Tese (Doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico.Estudou-se a brasagem sem fluxo entre aço carbono e cobre buscando avaliar a influência dos materiais base, dos metais de adição, das atmosferas de brasagem e do ciclo térmico na qualidade final da junta brasada. As brasagens foram realizadas utilizando metais de adição convencionais contendo Ag-Cu, Ag-Cu-Sn e Ag-Cu-Zn-Sn na forma de arame, ou através de revestimento de Sn, pela técnica conhecida como união por fase líquida transiente. Alto vácuo, médio vácuo, nitrogênio e mistura argônio-hidrogênio serviram como atmosferas de brasagem. A qualidade da junta brasada com metais de adição convencionais pode ser avaliada pela presença de defeitos, tais como pequenos rechupes, falhas de enchimento e até mesmo a presença de trincas. A ocorrência destes defeitos depende da combinação metal de adição/atmosfera de brasagem e da temperatura de brasagem utilizadas. O alto vácuo mostrou-se como a melhor atmosfera de b...
ABSTRACT O objetivo deste trabalho foi estudar a influência da corrente de soldagem sobre o rendi... more ABSTRACT O objetivo deste trabalho foi estudar a influência da corrente de soldagem sobre o rendimento bruto de fusão em soldagem MIG/MAG, levando-se em consideração as dimensões da peça. Para isto, foram feitas soldagens sobre chapas de três espessuras em uma faixa de corrente, utilizando-se o processo MIG/MAG CMT com o auxílio de uma unidade robótica. A escolha desse processo se deu para minimizar o efeito mecânico do arco no rendimento bruto de fusão, fato experimentalmente comprovado no trabalho. Foi verificado que o aumento da corrente e/ou redução da combinação espessura-largura da chapa fazem aumentar o rendimento bruto de fusão. Mas a intensidade do efeito da corrente depende da combinação espessura-largura da chapa. Abstract: The objective of the present paper was to study the influence of the welding current on the gross fusion efficiency in MIG/MAG welding, taking into account the plate dimensions. A series of weldments were carried out over three thickness plates in a current range utilizing the MIG/MAG CMT process, aided by a robotic unity. The choice of the process aimed to minimize the arc mechanical effect on the gross fusion efficiency, fact experimentally checked in the work. It was verified that an increase of current and/or reduction in the thickness-width combination leads to higher gross fusion efficiency. However, the intensity of the current effect depends on the thickness-width combination
ABSTRACT Mainly due to their great toughness, martensitic stainless steels are used for manufactu... more ABSTRACT Mainly due to their great toughness, martensitic stainless steels are used for manufacturing hydraulic turbines. However, these steels have some restrictions regarding regions recovered by welding, mainly due to the formation of non-quenched martensite, which causes a reduction in toughness. Considering repair of hydraulic turbines, there is a great interest in developing welding procedures that increase impact toughness and avoid post-welding heat treatment (TTPS). This study aims to analyse the influence of interpass temperature on microstructure, impact toughness and fatigue crack propagation in multipass welded joints on martensitic stainless steel CA6NM, using AWS410NiMo filler metal and the gas tungsten arc welding (GTAW) process. In the sample with interpass temperature of 80°C, influence of the interpass temperature on the formation of ferrite δ, with intragranular formation in the two-phase δ field, was observed, while in the sample welded at 150°C, the formation of ferrite δδ occurred mainly in the single-phase field. The change in the formation of ferrite δ, with the low interpass temperature, promoted an increase in impact toughness and a decrease in the fatigue crack propagation when compared with the sample welded with a higher interpass temperature. The results obtained indicate that the TIG process is an excellent alternative for the repair of CA6NM steel, with a significant influence from the interpass temperature.
As capas de eletrodos utilizados na soldagem por resistência por pontos (solda ponto) sofrem desg... more As capas de eletrodos utilizados na soldagem por resistência por pontos (solda ponto) sofrem desgaste durante a soldagem de chapas galvanizadas, devido ao elevado aquecimento e pressão na sua superfície. Neste trabalho avaliou-se a influência do desgaste sofrido por diferentes tipos de capas de eletrodos sobre as propriedades mecânicas e acabamento do ponto de solda. Observou-se que o desgaste varia de acordo com a capacidade de retenção de dureza a quente, e que a superfície das capas sofre intensa reação com o zinco da chapa galvanizada. Como conseqüência do desgaste das capas de eletrodo, o ponto de solda sofre redução progressiva do seu diâmetro (o que pode comprometer sua integridade estrutural), além de uma piora significativa do seu acabamento superficial.
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