scholarly journals COMPOSITE MATERIALS BASED ON CEMENT BINDERS MODIFIED WITH SiO2 NANOADDITIVES

2017 ◽  
Vol 16 (6) ◽  
pp. 459-465
Author(s):  
B. M. Khroustalev ◽  
S. N. Leonovich ◽  
V. V. Potapov ◽  
E. N. Grushevskaya
Keyword(s):  
Corrosion Resistance ◽  
Materials Science ◽  
Ionic Composition ◽  
Construction Materials ◽  
Operational Reliability ◽  
Strength Development ◽  
Ultrasonic Processing ◽  
Structure And Properties ◽  
Urgent Task ◽  
High Level

Development of nanotechnologies allows to solve a number of problems of construction materials science: increase in strength, durability, abrasion and corrosion resistance that determines operational reliability of building constructions. Generally it is achieved due to nanoparticles that modify the structure and properties of the existing materials or products and are entered into their volume or on a surface layer. It’s theoretically and experimentally proved that the modified water has the bigger activity owing to the change of the ionic composition influencing the рН size and other parameters. As nanoparticles have a high level of surface energy, they show the increased tendency to agglomeration, meanwhile the size of agglomerates can reach several micrometers. In this regard an urgent task is to equally distribute and disaggregate the nanoparticles in the volume of tempering water. The experiments on studying of influence of the nanoparticles of silica distributed in volume of liquid by means of ultrasonic processing on characteristics of cement and sand solution and heavy concrete have been conducted. Nanoadditive influence on density, speed of strength development, final strength under compression of materials on the basis of cement depending on nanoadditive mass percent has been established.

AL 4565 ALLOY

Alloy Digest ◽  
2004 ◽  
Vol 53 (8) ◽  
Keyword(s):  
Fracture Toughness ◽  
Corrosion Resistance ◽  
High Temperature ◽  
High Resistance ◽  
Flue Gas ◽  
Heat Treating ◽  
Flue Gas Desulfurization ◽  
High Nitrogen ◽  
Temperature Performance ◽  
High Level

Abstract AL 4565 alloy has a high level of austenitizers, which provides the microstructure with a high resistance to sigma formation during welding. The high nitrogen also gives the alloy superior strength among the austenitics. Applications include flue gas desulfurization and handling seawater. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as heat treating and joining. Filing Code: SS-906. Producer or source: Allegheny Ludlum Corporation.

scholarly journals Uncovering the superior corrosion resistance of iron made via ancient Indian iron-making practice

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Deepak Dwivedi ◽  
Jitendra P. Mata ◽  
Filomena Salvemini ◽  
Matthew R. Rowles ◽  
Thomas Becker ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Materials Science ◽  
Scientific Explanation ◽  
Central India ◽  
Protective Mechanisms ◽  
Excellent Corrosion Resistance ◽  
Metal Treatment ◽  
Indian Tribes ◽  
Superior Corrosion Resistance ◽  
Metallurgical Processes

AbstractAncient Indian iron artefacts have always fascinated researchers due to their excellent corrosion resistance, but the scientific explanation of this feature remains to be elucidated. We have investigated corrosion resistance of iron manufactured according to traditional metallurgical processes by the Indian tribes called ‘Agaria’. Iron samples were recovered from central India (Aamadandh, Korba district, Chhattisgarh). Iron artefacts are investigated using a range of correlative microscopic, spectroscopic, diffraction and tomographic techniques to postulate the hidden mechanisms of superlative corrosion resistance. The importance of manufacturing steps, ingredients involved in Agaria’s iron making process, and post-metal treatment using metal-working operation called hot hammering (forging) is highlighted. This study also hypothesizes the probable protective mechanisms of corrosion resistance of iron. Findings are expected to have a broad impact across multiple disciplines such as archaeology, metallurgy and materials science.

scholarly journals Fabrication of Superhydrophobic AA5052 Aluminum Alloy Surface with Improved Corrosion Resistance and Self Cleaning Property

Coatings ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 390 ◽  
Author(s):  
Qian Zhao ◽  
Tiantian Tang ◽  
Fang Wang
Keyword(s):  
Contact Angle ◽  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Materials Science ◽  
Composite Coatings ◽  
Alloy Surface ◽  
Corrosion Resistant ◽  
Self Cleaning ◽  
Aa5052 Aluminum Alloy ◽  
Aluminum Alloy Surface

The development of a self-cleaning and corrosion resistant superhydrophobic coating for aluminum alloy surfaces that is durable in aggressive conditions has attracted great interest in materials science. In the present study, a superphydrophobic film was fabricated on an AA5052 aluminum alloy surface by the electrodeposition of Ni–Co alloy coating, followed by modification with 6-(N-allyl-1,1,2,2-tetrahydro-perfluorodecyl) amino-1,3,5-triazine-2,4-dithiol monosodium (AF17N). The surface morphology and characteristics of the composite coatings were investigated by means of scanning electron microscopy (SEM), energy dispersive X-ray spectrum (EDS), atomic force microscope (AFM) and contact angle (CA). The corrosion resistance of the coatings was assessed by electrochemical tests. The results showed that the surface exhibited excellent superhydrophobicity and self-cleaning performance with a contact angle maintained at 160° after exposed to the atmosphere for 240 days. Moreover, the superhydrophobic coatings significantly improved the corrosion resistant performance of AA5052 aluminum alloy substrate in 3.5 wt.% NaCl solution.

scholarly journals РОЗРОБКА ІНСТРУМЕНТАЛЬНОГО МЕТОДУ ДОСЛІДЖЕННЯ ФАКТУРИ ТКАНИНИ

World Science ◽  
2020 ◽  
Vol 1 (3(55)) ◽  
pp. 17-25
Author(s):  
Нода О. М. ◽  
Закора О. В. ◽  
Рязанова О. Ю.
Keyword(s):  
Tissue Sample ◽  
Objective Assessment ◽  
Instrumental Method ◽  
Structure And Properties ◽  
Textile Production ◽  
Qualitative And Quantitative ◽  
Urgent Task ◽  
Quantitative Characteristics ◽  
Tactile Sensations ◽  
Qualitative And Quantitative Characteristics

Modern consumers attach increasing importance to tactile sensations and the general perception of the surface of fabrics, therefore, the study of the structure and properties of woven textures is an urgent task of textile production. In textile technologies, organoleptic research methods are used mainly, which give a subjective visual and tactile assessment of the surface of the tissues. Therefore, there was a need to develop an instrumental method for determining the texture of fabrics, which was implemented on the basis of the existing method for studying the texture of hard surfaces. It is based on the idea of creating a constant mode of illumination of the object of observation, which is a tissue sample. The proposed method is based on the use of a special optical device for determining the qualitative and quantitative characteristics of textures and is a viewing chamber containing a mechanism for changing the lighting mode and a mechanism for capturing tissue images. For an objective assessment of the state of the surface of the tissues, the invoice indicator is calculated − the invoice coefficient. The implementation of the developed method allows to increase the efficiency of the processes of design-design of fabrics, to predict the appearance of fabrics and to ensure compliance with the texture of the fabric of the model of the garment.

Development of Ips Learning Module Based on Islamic Integration and Science In Grade VII Students SMP Muhammadiyah Enrekang

2021 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Tri Wijaya Darwis ◽  
Muhammad Ibrahim ◽  
Suparman Suparman ◽  
Putriyani Samsul
Keyword(s):  
Learning Outcomes ◽  
Materials Science ◽  
Field Tests ◽  
Design Development ◽  
Development Models ◽  
Post Test ◽  
Development Approach ◽  
High Level ◽  
Module Development ◽  
Expert Validation

The IPS module development based on Islamic integration and science in SMP Muhammadiyah Enrekang based on: First, no SCIENCE teaching materials have the concept of Islamic integration and science. Second, no teaching material guides students to obtain IPS' idea confidence in Allah SWT. Third, the results of studying IPS are some students who have not achieved KKM scores. The purpose of this development are to: (1) design the of Islamic-based IPS modules and human materials science, place and environment in grade VII students of SMP Muhammadiyah Enrekang, (2) explain the effectiveness Islamic-based IPS modules to improve learning outcomes. This research used a Research and Development approach with ADDIE (Analysis, Design, Development, Implementation, and Evaluation) development models. An explanation of the module's level of interest was used in the questionnaire tested in the experiment class. Meanwhile, the influence of modules on improving students' learning outcomes uses pre-test post-test control design groups. The development results showed that: (1) specifications of IPS modules based on Islamic integration and science in the form of print media. This module developed using evidence sourced from the Qur'an. The learning results intended to achieve 2013 curriculum and as a means for students to increase their confidence in Allah SWT through integration with the evidence of the Qur'an; (2) the effectiveness and convenience of IPS module based on Islamic integration and science showed that this module has a high level of feasibility, effectiveness, and interest. 84% level material validation results evidence this, 71% level learning expert validation, 95% level language validation, 90% learning expert validation. The results of field tests on grade VII students of SMP Muhammadiyah Enrekang showed a high level of effectiveness through the works of independent sample t-test obtained t count=6.41and t tabel=2.0322. Because of the t count > table, Ho is rejected, and Ha is accepted

Assessment of the technical condition of mines with mechanical fuses

2021 ◽  
Vol 2021 (1) ◽  
pp. 1-12
Author(s):  
Adam Kubecki ◽  
Cezary Śliwiński ◽  
Janusz Śliwiński ◽  
Ireneusz Lubach ◽  
Leszek Bogdan ◽  
...  
Keyword(s):  
Construction Materials ◽  
Armed Forces ◽  
Operational Reliability ◽  
Strength Properties ◽  
Technical Condition ◽  
Armed Conflicts ◽  
Long Term Storage ◽  
Precise Adjustment ◽  
Main Charge ◽  
Materials Used

Contemporary armed conflicts reveal that the use of effective mine barriers has a significant impact on the course of hostilities. Therefore, the Polish Armed Forces selected reliable and effective explosive ordnance as a priority, both newly-acquired material and those currently in operation. For this reason, among others, strict supervision over the technical condition of mines is exercised, in particular during their long-term storage. The reasons behind the increased mine unreliability may include physical and chemical changes in the construction materials used (corrosion, deformations, loss of strength properties), deterioration of the physicochemical properties of the main charge, booster and primer-detonator, inadequate technical condition of the safety components, or the failure of mine fuse mechanisms. In order to assess the mine's operational reliability, each mine fuse subassembly is examined and then a check of the entire assembled mine is performed. This requires proper planning of the full test cycle and the use of inspected and calibrated measuring devices and test stands enabling the precise adjustment of mechanical and climatic stress parameters.

Microstructural Analysis of Changes in the Morphology of Quartz Raw Materials of Different Genesis at Dry Milling

2021 ◽  
Vol 1017 ◽  
pp. 91-100
Author(s):  
Ekaterina V. Fomina ◽  
Natalia I. Kozhukhova ◽  
Evgeny A. Belovodsky ◽  
V.A. Klimenko ◽  
Marina I. Kozhukhova
Keyword(s):  
Materials Science ◽  
Fine Particles ◽  
Raw Materials ◽  
Microstructural Analysis ◽  
Construction Materials ◽  
Degree Of Crystallinity ◽  
Energy Potential ◽  
Natural Quartz ◽  
Defective Structure ◽  
Dry Grinding

The influence of the genesis of quartz-containing rocks on the strength of particles and changes in morphology during destruction from the standpoint of the mineralogical approach in the development of the scientific direction "geonics" ("geomimetics") has been investigated. The kinetics of dry grinding of raw materials in a laboratory ball roller mill was carried out. The features of the formation and development of cracks, particle size distribution, changes in the morphology and microstructure of fragments have been studied. It was found that in natural quartz cracks develop along the surface, where the highest concentration of impurities creates a defect structure with destruction into small particles. The purest structure of hydrothermal quartz is susceptible to brittle fracture into fragments similar in morphology to the base particle. Reducing the defectiveness of the structure increases the strength of the crystals. The internal energy potential of techno genic raw materials is determined by its defective structure, which undergoes the greatest deformations during grinding, allowing obtaining the maximum values of the specific surface area and reduce the grinding time. A difference in the degree of crystallinity of quartz, which composes the polymineral techno genic raw materials, makes it possible to obtain the optimal granulometry of fine particles. The conducted research is aimed at identifying the mechanisms of destruction of quartz rocks and can be used in solving engineering problems not only in construction materials science, but also in geotechnics.

scholarly journals Effect of Soil Organic Matters in Dredged Soils to Utilization of their Mixtures Made with a Steel Slag

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5450
Author(s):  
Kanako Toda ◽  
Ryosuke Kikuchi ◽  
Tsubasa Otake ◽  
Satoshi Nishimura ◽  
Yuzoh Akashi ◽  
...  
Keyword(s):  
Humic Acid ◽  
Steel Slag ◽  
Construction Materials ◽  
Engineering Application ◽  
Pozzolanic Reaction ◽  
Strength Development ◽  
Organic Matters ◽  
Development Indicators ◽  
Dredged Soil ◽  
Accelerate Evaluation

Dredged soils have been used as construction materials by alkaline activation with steel slag (steel slag-dredged soil mixtures) at harbors. Such mixtures develop strength chiefly by calcium silicate hydrate (C-S-H) formation by the pozzolanic reaction. However, the strength of such mixtures is unpredictable, and in some cases, mixtures have been too soft for the intended engineering application. An identification of strength development indicators would accelerate evaluation processes for strength development to facilitate and promote the utilization of such materials. This paper focuses on the relationship between the characteristics of soil organic matters in dredged soils and the strength development of the mixtures by a comparison of eight dredged soils collected from eight different Japanese harbors. The characteristics of the soil organic matters were identified to determine as indicators of mixtures with weak strength development, i.e., enriched sulfur content in extracted soil organic matter (humic acid) fraction, and the N/C ratio of humic acid similar to land humic acid standards. Increases in the validated fraction of dredged soils and steel slag by replacing fractions disadvantageous to construction resources would contribute to reduce waste production, which would lower the environmental impact of the use, aiming to achieve sustainable utilization of such materials.

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