cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14321987
title: Study of the influence of the replacement of Portland cement by red ceramic residue in the manufacture of fiber cement boards

description: ABSTRACT Currently, the waste of the red ceramic industry presented as a potential alternative for use in cementitious matrices such as mineral or pozzolan addition of low reactivity. This study had as objective evaluate the influence of partial replacement of CP V ARI cement by the red ceramic industrywaste on fiber cement plates. The cement was replaced to volume in the percentages of 0, 15, 25 and 50%. These combinations were reinforced with cellulose and polypropylene (PP) fibers. The investigation was perform tests including X-ray diffraction, scanning electron microscopy and thermogravimetric Analysis. Moreover, mechanical flexural strength tests of the boards were performed on samples produced based on a suction and pressing process. All test were performed with samples at 28 days of hydration. The results of the microstructural characterization showed a reduction of calcium hydroxide as the RCV content increases, due to the consumption of this compound as result of the pozzolanic reaction, C-S-H peaks were also observed in all mixtures. Considering the results of the flexural mechanical properties, all percentages of substitution presented satisfactory results in accordance with the NBR 15498 standard referring flexural strength for use on external facades.
DOI: 10.6084/m9.figshare.14321988
title: Experimental investigation on flexural performance of functionally graded concrete beams using flyash and red mud

description: ABSTRACT The continuous change in the strength and other properties, environmental problems, hike in cement price, advancement of construction industry makes the usage of alternative materials as Functionally graded materials (FGM) which leads to a new materials on concrete as Functionally graded concrete (FGC), In this present paper, investigation has carried out on the functionally graded concrete by using red mud and also fly ash. In this M20 grade of concrete is used as the conventional concrete in compression zone and M25 with the replacement of cement by red mud and flyash with varying percentage (5%, 10% 15%) respectively in the tension zone. The results indicated that the 10% of the red mud and 10% of the fly ash as the optimum value for the concrete beam and by load deflection curve, it is evident that functionally graded concrete beam has more advantages than ordinary concrete since it has more durability and strength characteristics. Scanning electron microscope analysis was also carried out on the red mud functionally graded concrete and fly ash functionally graded concrete. It clearly indicated the pores present in the materials which tends to increase in strength of the concrete.
DOI: 10.6084/m9.figshare.14321988.v1
title: Experimental investigation on flexural performance of functionally graded concrete beams using flyash and red mud

description: ABSTRACT The continuous change in the strength and other properties, environmental problems, hike in cement price, advancement of construction industry makes the usage of alternative materials as Functionally graded materials (FGM) which leads to a new materials on concrete as Functionally graded concrete (FGC), In this present paper, investigation has carried out on the functionally graded concrete by using red mud and also fly ash. In this M20 grade of concrete is used as the conventional concrete in compression zone and M25 with the replacement of cement by red mud and flyash with varying percentage (5%, 10% 15%) respectively in the tension zone. The results indicated that the 10% of the red mud and 10% of the fly ash as the optimum value for the concrete beam and by load deflection curve, it is evident that functionally graded concrete beam has more advantages than ordinary concrete since it has more durability and strength characteristics. Scanning electron microscope analysis was also carried out on the red mud functionally graded concrete and fly ash functionally graded concrete. It clearly indicated the pores present in the materials which tends to increase in strength of the concrete.
DOI: 10.6084/m9.figshare.14321991.v1
title: Influence of mineral additions on temperature increase of mass concrete of high compressive strength

description: ABSTRACT The construction of large foundation blocks for tall buildings has become common in the country. The high compressive strength of concretes, coupled with the fact that they are often self-compacting concretes, generally lead to high binder consumption, possibly causing problems of thermal origin to these structural elements. The objective of this study was to evaluate the influence of different mineral admixtures on the temperature rise of mass concrete with high compressive strength. For this, an adiabatic calorimeter was used, which simulates the condition of a concrete in an autogenous cure regime. The compressive strengths of the concretes in autogenous and ambient cure regimes were determined at 28 days. In addition, the pastes that composed the concretes were evaluated by thermogravimetric analysis at 28 days, in order to verify the influence of temperature on the reactions of the compounds of the mixtures. The results showed that there was a trend of lower heat release for the parameters °C/MPa and °C/kg of binder for CP III-RS, compared to the other binders used. Thermogravimetric analysis indicated that the type of curing did not significantly influence the pozzolanic activity and the hydration of the Portland cement. Finally, it was verified that the higher compressive strengths for the same water/binder ratio were obtained by the combination of CP V-ARI + metacaulim, because this mineral addition showed high pozzolanic activity. On the other hand, in the CP V - ARI + active silica combination, the mineral admixtures seems to have contributed predominantly to the formation of nucleation points, presenting low calcium hydroxide consumption.
DOI: 10.6084/m9.figshare.14321991
title: Influence of mineral additions on temperature increase of mass concrete of high compressive strength

description: ABSTRACT The construction of large foundation blocks for tall buildings has become common in the country. The high compressive strength of concretes, coupled with the fact that they are often self-compacting concretes, generally lead to high binder consumption, possibly causing problems of thermal origin to these structural elements. The objective of this study was to evaluate the influence of different mineral admixtures on the temperature rise of mass concrete with high compressive strength. For this, an adiabatic calorimeter was used, which simulates the condition of a concrete in an autogenous cure regime. The compressive strengths of the concretes in autogenous and ambient cure regimes were determined at 28 days. In addition, the pastes that composed the concretes were evaluated by thermogravimetric analysis at 28 days, in order to verify the influence of temperature on the reactions of the compounds of the mixtures. The results showed that there was a trend of lower heat release for the parameters °C/MPa and °C/kg of binder for CP III-RS, compared to the other binders used. Thermogravimetric analysis indicated that the type of curing did not significantly influence the pozzolanic activity and the hydration of the Portland cement. Finally, it was verified that the higher compressive strengths for the same water/binder ratio were obtained by the combination of CP V-ARI + metacaulim, because this mineral addition showed high pozzolanic activity. On the other hand, in the CP V - ARI + active silica combination, the mineral admixtures seems to have contributed predominantly to the formation of nucleation points, presenting low calcium hydroxide consumption.
DOI: 10.6084/m9.figshare.14321993
title: A digital torsimeter for torsion testing of materials and shear elasto-plastic parameters evaluation

description: ABSTRACT In this work, the project, the main components and the results obtained with the prototype of a digital torsiometer that was built to measure the variation of the torsion angle in mechanical tests of materials are shown. A magnetic encoder model AS5048A was used in this device. This encoder has 14 bits of resolution and an Arduino Mega 2560 microcontroller board was used for data processing. In addition to the low cost of electronic and mechanical components, another advantage of the measurement system developed is the large amount of free applications available for processing and acquiring data with the microcontroller board used. Tests were carried out to verify the accuracy in the angular variation readings and torsion tests with aluminum tubular specimens (AA6351T6 alloy) to evaluate the performance of the measurement system in monotonic tests. The Ramberg-Osgood relationship was used to describe the behavior of the material and the shear stresses were evaluated using nonlinear relationships proposed by different authors. The results obtained indicate that the digital torsiometer presented satisfactory results for obtaining the torsion angle and the main advantages of this device include the measurement of the non-contact torsion angle, linearity, good accuracy over the entire measurement range, unlimited measurement range, reduced size and low cost for confection.
DOI: 10.6084/m9.figshare.14321993.v1
title: A digital torsimeter for torsion testing of materials and shear elasto-plastic parameters evaluation

description: ABSTRACT In this work, the project, the main components and the results obtained with the prototype of a digital torsiometer that was built to measure the variation of the torsion angle in mechanical tests of materials are shown. A magnetic encoder model AS5048A was used in this device. This encoder has 14 bits of resolution and an Arduino Mega 2560 microcontroller board was used for data processing. In addition to the low cost of electronic and mechanical components, another advantage of the measurement system developed is the large amount of free applications available for processing and acquiring data with the microcontroller board used. Tests were carried out to verify the accuracy in the angular variation readings and torsion tests with aluminum tubular specimens (AA6351T6 alloy) to evaluate the performance of the measurement system in monotonic tests. The Ramberg-Osgood relationship was used to describe the behavior of the material and the shear stresses were evaluated using nonlinear relationships proposed by different authors. The results obtained indicate that the digital torsiometer presented satisfactory results for obtaining the torsion angle and the main advantages of this device include the measurement of the non-contact torsion angle, linearity, good accuracy over the entire measurement range, unlimited measurement range, reduced size and low cost for confection.
DOI: 10.6084/m9.figshare.14268579.v1
title: Influence of grape seed oil into recycled polypropylene (PP) thermo-oxidative degradation

description: ABSTRACT The antioxidant potential of grape seed oil (OSU) was evaluated after addition into recycled polypropylene (PP rec.). OSU was incorporated into PP rec. in variable contents of 0.5, 1.0 and 1.5 phr (per hundred resin). The processing was carried out in a twin-screw extruder and the different samples, after being granulated, were submitted to thermo-oxidative degradation by thermogravimetry (TGA). Experimental data were treated using an empirical methodology that combined kinetic models, present in the literature, and statistical tools such as analysis of variance (ANOVA). The results of thermo-oxidative degradation kinetics allowed us to conclude that OSU shows effective antioxidant activity only when the added content does not exceed 0.5 phr and low heating rates (3 °C/min) are considered.
DOI: 10.6084/m9.figshare.14268579
title: Influence of grape seed oil into recycled polypropylene (PP) thermo-oxidative degradation

description: ABSTRACT The antioxidant potential of grape seed oil (OSU) was evaluated after addition into recycled polypropylene (PP rec.). OSU was incorporated into PP rec. in variable contents of 0.5, 1.0 and 1.5 phr (per hundred resin). The processing was carried out in a twin-screw extruder and the different samples, after being granulated, were submitted to thermo-oxidative degradation by thermogravimetry (TGA). Experimental data were treated using an empirical methodology that combined kinetic models, present in the literature, and statistical tools such as analysis of variance (ANOVA). The results of thermo-oxidative degradation kinetics allowed us to conclude that OSU shows effective antioxidant activity only when the added content does not exceed 0.5 phr and low heating rates (3 °C/min) are considered.
DOI: 10.6084/m9.figshare.14321994
title: Evaluation of structural adhesive joints fracture toughness without crack measurement

description: ABSTRACT The adhesive fracture resistance of structural adhesive joints in mode II, ��IIC, is accessed through the application of two models that prescind of the measurement of the crack length during the subjection of ENF specimens to three-point bending monotonic tests. The load vs transversal displacement results are used in two different approaches: a damage model and a cohesive zone model. The first one was used in test where the crack propagation was unstable and the second one was used for stable crack propagations. These initial results show the viability of the models and show that both: initial crack length and transversal load rate; have great influence in ��IIC evaluation.
DOI: 10.6084/m9.figshare.14321994.v1
title: Evaluation of structural adhesive joints fracture toughness without crack measurement

description: ABSTRACT The adhesive fracture resistance of structural adhesive joints in mode II, ��IIC, is accessed through the application of two models that prescind of the measurement of the crack length during the subjection of ENF specimens to three-point bending monotonic tests. The load vs transversal displacement results are used in two different approaches: a damage model and a cohesive zone model. The first one was used in test where the crack propagation was unstable and the second one was used for stable crack propagations. These initial results show the viability of the models and show that both: initial crack length and transversal load rate; have great influence in ��IIC evaluation.
DOI: 10.25919/x431-5p42
title: Parkes observations for project P1071 semester 2020OCTS_05

description: Intermittent pulsars are a major topic of current pulsar research as they provide a direct link between studies of pulsar emission and irregularities in the rotation of the pulsars. The new Ultra-Wide-Low(UWL) receiver provides unprecedented frequency coverage and will allow us to study the emission properties of the intermittent pulsars in great detail. We request observations with the UWL receiver to intermittent pulsars. These are pulsars whose emission switches on and off at long intervals from days to years. We will determine the distribution and frequency dependence of the time scales, look for weak or bursty emission in the off states and determine the bandwidth of the on/off emission process, the spectral characteristics of the emission, the evolution of pulse energy distribution over wide-band and search for possible link between long- and short-term emission variability. These observations will provide insights into how these pulsars emit and how that emission is changing in time and as a function of frequency.
DOI: 10.6084/m9.figshare.14321999.v1
title: Effect of stress relief heat treatment and preheating on the microstructure and microhardness of the interface between Inconel 625 deposit and AISI 8630M and AISI 4130 steels

description: ABSTRACT The objective of this study was to evaluate the effect of the preheating and interpass temperature, as well as to evaluate the effect of the application of stress relief heat treatment on the microstructure, microhardness and composition gradient along the interface of AWS E NiCrMo3 alloy on AISI8630M and AISI4130 quenched and tempered steel, applied by two welding process. For this superimposed weld beads using different preheat and interpass were applied using MIG and Plasma Transfered Arc – Powder (PTA-P) welding process. The interfaces deposits were subjected to analysis of chemical composition by EDS, to metallographic examination by optical and electronic microscopy and to microhardness tests. The increase in preheat and interpass temperatures resulted in greater grain refinement of the first pass, increase of heat affected zone microhardness and in a greater Fe migration from the substrate to the applied layer. A minor frequency diversity and a lower incidence of partially diluted zones (PDZ) was observed in deposits performed by PTA-P process, where as the deposits performed with MIG process discontinuous PDZ type with different morphologies were identified. The use of stress relief heat treatment resulted in a significant reduction in microhardness values in all cases.
DOI: 10.6084/m9.figshare.14321999
title: Effect of stress relief heat treatment and preheating on the microstructure and microhardness of the interface between Inconel 625 deposit and AISI 8630M and AISI 4130 steels

description: ABSTRACT The objective of this study was to evaluate the effect of the preheating and interpass temperature, as well as to evaluate the effect of the application of stress relief heat treatment on the microstructure, microhardness and composition gradient along the interface of AWS E NiCrMo3 alloy on AISI8630M and AISI4130 quenched and tempered steel, applied by two welding process. For this superimposed weld beads using different preheat and interpass were applied using MIG and Plasma Transfered Arc – Powder (PTA-P) welding process. The interfaces deposits were subjected to analysis of chemical composition by EDS, to metallographic examination by optical and electronic microscopy and to microhardness tests. The increase in preheat and interpass temperatures resulted in greater grain refinement of the first pass, increase of heat affected zone microhardness and in a greater Fe migration from the substrate to the applied layer. A minor frequency diversity and a lower incidence of partially diluted zones (PDZ) was observed in deposits performed by PTA-P process, where as the deposits performed with MIG process discontinuous PDZ type with different morphologies were identified. The use of stress relief heat treatment resulted in a significant reduction in microhardness values in all cases.
DOI: 10.6084/m9.figshare.14322000
title: Mössbauer spectroscopy and Rietveld refinement used to analyze stainless steel properties regarding shape memory effect (SME)

description: ABSTRACT The resonant absorption of recoilless g-rays, known as Mössbauer Spectroscopy, is an efficient nuclear prospecting technique to structural and magnetic analysis. When studying steels, it is possible to accurately analyze the surface of materials using the Conversion Electron Mössbauer Spectroscopy technique (CEMS) that evaluates the sample’s surface to a depth of 200 nm, and by Conversion X-ray Mössbauer Spectroscopy by (CXMS), which can go deeper and investigate inner layers of steel samples (10 mm). In this work, this technique was employed to study the crystallographic reversion (f.c.c.àh.c.p.) of stainless steel shape memory. A hexagonal martensitic phase was induced mechanically through the compression test and the reversion to austenite phase was observed using heat treatment. Mössbauer spectroscopy measurements were carried out using the conversion of electrons, and X-ray with a 57Co source in a rhodium matrix at room temperature and without the external fields. Spectra were analyzed using specific adjustment software. The results indicated great reversal of e-martensite. Rietveld refinement analysis was obtained using the XRD data to evaluate possible structural changes occurring during the thermo-mechanical treatment (cycles of deformation followed by heating). Comparison of the Mössbauer spectra and Rietveld refinement are important for understanding the reversal of the martensitic phase. In this case, the crystal structure changes resulted in a shape recovery material, which was deformed beyond its elastic limit.
DOI: 10.6084/m9.figshare.14322000.v1
title: Mössbauer spectroscopy and Rietveld refinement used to analyze stainless steel properties regarding shape memory effect (SME)

description: ABSTRACT The resonant absorption of recoilless g-rays, known as Mössbauer Spectroscopy, is an efficient nuclear prospecting technique to structural and magnetic analysis. When studying steels, it is possible to accurately analyze the surface of materials using the Conversion Electron Mössbauer Spectroscopy technique (CEMS) that evaluates the sample’s surface to a depth of 200 nm, and by Conversion X-ray Mössbauer Spectroscopy by (CXMS), which can go deeper and investigate inner layers of steel samples (10 mm). In this work, this technique was employed to study the crystallographic reversion (f.c.c.àh.c.p.) of stainless steel shape memory. A hexagonal martensitic phase was induced mechanically through the compression test and the reversion to austenite phase was observed using heat treatment. Mössbauer spectroscopy measurements were carried out using the conversion of electrons, and X-ray with a 57Co source in a rhodium matrix at room temperature and without the external fields. Spectra were analyzed using specific adjustment software. The results indicated great reversal of e-martensite. Rietveld refinement analysis was obtained using the XRD data to evaluate possible structural changes occurring during the thermo-mechanical treatment (cycles of deformation followed by heating). Comparison of the Mössbauer spectra and Rietveld refinement are important for understanding the reversal of the martensitic phase. In this case, the crystal structure changes resulted in a shape recovery material, which was deformed beyond its elastic limit.
DOI: 10.6084/m9.figshare.14322002.v1
title: Plasma nitriding and deposition in AISI M2 and D2 steel tools used in nail forming and stamping: a viability study

description: ABSTRACT The growing need to increase the productivity of the industrial sector, drives the development of new steels and new treatments that can improve the performance and useful life of cutting, forming and stamping tools. Plasma-assisted surface treatments stand out in this context. Previous research has shown that these coatings are efficient in increasing hardness, wear resistance and corrosion resistance of different types of steels. In this sense, samples and tools from AISI M2 and D2 heat-treated steels were subjected to conventional plasma nitriding processes, in cathodic cage and duplex treatment in order to evaluate the effect of these treatments on forming tools seeking the viability of applying the method in the industrial sector with the reduction of the manufacturing cost in the conformation and stamping of nails. Vickers microhardness tests, SEM analysis and X-Ray Diffraction (XRD) made it possible to identify mechanical properties, layer of compounds and the phases present, respectively. The performance of the tools was based on the volume of nails produced in kg. The productive cost was determined in function of productivity, the purchase price of the tool and the nitriding price. The use of plasma nitriding proved to be feasible for both steels, highlighting the fact that the D2 steel tools nitrided at 480ºC for 3 hours, obtained the greatest productivity gains in relation to non-nitrided tool. The application of conventional nitriding in the steel tool M2 at 480ºC for 4 hours made it possible to reduce its cost by 26% and reduce by 3.5% the total cost of producing nails, obtaining the best cost-benefit ratio.