Investigation of Electroplastic Effect on Four Grades of Duplex Stainless Steels

Since the late 1950s, an effect of electrical current in addition to joule heating on the deformation of metals called the Electroplastic Effect (EPE) has been known. It is used nowadays in the so-called Electrically Assisted Forming (EAF) processes, but the understanding of the phenomenon is not very clear yet. It has been found that EPE increases the formability of high stacking fault energy (SFE) materials, while low SFE materials reach fracture prematurely. Since Duplex Stainless Steels (DSSs) possess a microstructure consisting of two phases with very different SFE (low SFE austenite and high SFE ferrite) and they are widely used in industry, we investigated EPE on those alloys. Tensile tests at 5 A/mm2, 10 A/mm2 and 15 A/mm2 current densities along with thermal counterparts were conducted on UNS S32101, UNS S32205, UNS S32304 and UNS S32750. The DSS grades were characterized by means of optical microscopy, X-ray diffraction and their mechanical properties (ultimate tensile strength, total elongation, uniform elongation and yield stress). An increase in uniform elongation for the electrical tests compared to the thermal counterparts as well as an increase in total elongation was found. No differences were observed on the yield stress and on the ultimate tensile strength. Un uneven distribution of the current because of the different resistivity and work hardening of the two phases has been hypothesized as the explanation for the positive effect of EPE

An effaced horseshoe crab (Arthropoda: Chelicerata: Xiphosura) from the Upper Carboniferous of the Carnic Alps (Friuli, NE Italy)

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.A carapace of a new horseshoe crab (Arthropoda: Chelicerata: Xiphosura) is described from the Upper Carboniferous (Kasimovian) Meledis Formation of the Carnic Alps, Friuli, Italy. It is named as Stilpnocephalus pontebbanus n. gen. & n. sp., and belongs to the family Belinuridae Zittel in Zittel & Eastman, 1913. The large (>8 cm width) carapace is strongly effaced and appears to lack eyes. The new specimen is the first fossil horseshoe crab to be described from Italy and the largest known belinurid

A fossil whip-scorpion (Arachnida: Thelyphonida) from the Upper Carboniferous of the Carnic Alps (Friuli, NE Italy)

A new and well-preserved fossil whip scorpion (Arachnida: Uropygi: Thelyphonida) is described from the Late Carboniferous of the Carnic Alps, Friuli, Italy. It is referred to Parageralinura marsiglioi n. sp. The new specimen is the first Carboniferous arachnid to be described from mainland Italy and is possibly the youngest Palaeozoic thelyphonid

A FOSSIL WHIP-SCORPION (ARACHNIDA: THELYPHONIDA) FROM THE UPPER CARBONIFEROUS OF THE CARNIC ALPS (FRIULI, NE ITALY)

A new and well-preserved fossil whip scorpion (Arachnida: Uropygi: Thelyphonida) is described from the Late Carboniferous of the Carnic Alps, Friuli, Italy. It is referred to Parageralinura marsiglioi n. sp. The new specimen is the first Carboniferous arachnid to be described from mainland Italy and is possibly the youngest Palaeozoic thelyphonid

Lochkovian conodonts in the Rio Malinfier West section

The Lockhovian conodont fauna from the new Rio Malinfier section is discussed and commented

AN EFFACED HORSESHOE CRAB (ARTHROPODA: CHELICERATA: XIPHOSURA) FROM THE UPPER CARBONIFEROUS OF THE CARNIC ALPS (FRIULI, NE ITALY)

A carapace of a new horseshoe crab (Arthropoda: Chelicerata: Xiphosura) is described from the Upper Carboniferous (Kasimovian) Meledis Formation of the Carnic Alps, Friuli, Italy. It is named as Stilpnocephalus pontebbanus n. gen. & n. sp., and belongs to the family Belinuridae Zittel in Zittel & Eastman, 1913. The large (>8 cm width) carapace is strongly effaced and appears to lack eyes. The new specimen is the first fossil horseshoe crab to be described from Italy and the largest known belinurid

Genetic algorithms for hyperparameter optimization in predictive business process monitoring

Predictive business process monitoring exploits event logs to predict how ongoing (uncompleted) traces will unfold up to their completion. A predictive process monitoring framework collects a range of techniques that allow users to get accurate predictions about the achievement of a goal for a given ongoing trace. These techniques can be combined and their parameters configured in different framework instances. Unfortunately, a unique framework instance that is general enough to outperform others for every dataset, goal or type of prediction is elusive. Thus, the selection and configuration of a framework instance needs to be done for a given dataset. This paper presents a predictive process monitoring framework armed with a hyperparameter optimization method to select a suitable framework instance for a given dataset

Carta de restauração dos fósseis

A Itália é um país com forte tradição no campo da restauração. Não surpreende, portanto, que a Carta de Restauração dos Fósseis tenha nascido em contexto italiano. O documento, publicado em 1998, organiza e sistematiza informações sobre cada atividade que possa influenciar na longevidade do fóssil, desde a escavação até o momento de guarda em uma instituição. Apesar de muitos dos pontos abordados serem intrínsecos do “fazer paleontologia”, algumas questões nos parecem relevantes para profissionais que queiram tratar de fósseis. Algo importante a enfatizar, por exemplo, é a inclusão de informações de campo, de preparação e conservação na documentação do registro na coleção científica – dados já apontados para uma documentação museológica. Outro ponto importante a destacar é a necessidade das instituições de prover laboratórios de preparação, restauração e conservação para os vários objetos de pesquisa, com profissionais qualificados nas diversas áreas de conhecimento necessárias para estas atividades. Infelizmente, isso ocorre pontualmente em certas instituições. Acreditamos que as normas de restauração e de conservação de fósseis, normalmente dispersas em várias bibliografias, foram habilmente sintetizadas na presente carta, favorecendo o conhecimento dos princípios básicos dos critérios de base e normas a serem seguidas para a coleta, preparação, restauração e conservação de material fóssil. E, ainda que a realidade italiana seja diversa da brasileira em muitos aspectos, as boas práticas indicadas no texto têm o potencial de servir de norte para políticas de gestão de coleções paleontológicas. Por fim, agradecemos ao Dr. Vittorio Borselli, coordenador da presente Carta, por conceder a autorização para tradução do documento, e assim, proporcionar sua difusão abrangente entre os profissionais que trabalham com a curadoria de material paleontológico no Brasil