Investigation of the Physical and Mechanical Properties and Chemical Composition of Bambusa rigida Before and After Accelerated Aging

Aim. To evaluate the potential utility of fibrin matrices containing 10, 20, and 25 mg/ml of fibrinogen (fibrin-10, fibrin-20, and fibrin-30, respectively) in vascular tissue engineering (VTE). Materials and Methods. Fibrinogen was isolated using the method of ethanol cryoprecipitation and polymerized using a solution of thrombin and CaCl2. The fibrin structure was studied in a scanning electron microscope, and the physical and mechanical properties of the material were tested on a Zwick/Roell test machine. The metabolic activity of endothelial cells (EC) on the fibrin surface was evaluated by the MTT assay, and the viability of fibroblasts in the thickness of fibrin and possibility for migration by in fluorescent and light microscopy. Percent of fibrin shrinkage was determined from the difference in the sample volumes before and after removal of moisture. Results. The fiber diameter did not differ among all fibrin samples, but the pore diameter in fibrin-30 was smaller than those in fibrin-10 and fibrin-20. A possibility for migration of fibroblasts into the depth of the fibrin matrix and preservation of 97-100% viability of cells at a depth 5 mm was confirmed. The metabolic activity of EC on the surface of fibrin-20 and fibrin-30 exceeded that on collagen, fibronectin, and fibrin-10. All fibrin samples shrank in volume to 95.5-99.5%, and the highest shrinkage was seen in fibrin-10. The physical and mechanical properties of fibrin were inferior to those of human A. mammaria by a factor of 10. Conclusion. Fibrin with fibrinogen concentrations of 20 and 30 mg/ml maintains a high metabolic and proliferative activity of EC on the surface and also a high viability of fibroblasts in the matrix. Its availability, ease of preparation, and a number of other favorable properties make fibrin a promising material for VTE. However, the problem of insufficient strength requires further investigations.

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Analysis of Wear-Resistant Materials of Mixer - Pneumosuperchargers Blades Operating under Conditions of Abrasive Wear

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.316.893 ◽

2021 ◽

Vol 316 ◽

pp. 893-898

Author(s):

Natalya Gabelchenko ◽

Artem Belov ◽

Artem Kravchenko ◽

Oleg Kryuchkov

Keyword(s):

Mechanical Properties ◽

Weight Loss ◽

Wear Resistance ◽

Chemical Composition ◽

Abrasive Wear ◽

Abrasive Medium ◽

Wear Resistant ◽

Comparative Tests ◽

Before And After ◽

110G13l Steel

We conducted comparative tests of the wear resistance of metals operating under abrasive conditions. Samples were cut from the working parts of mixer-pneumosuperchargers. The chemical composition and mechanical properties were determined. To compare samples under abrasive wear conditions, we designed and assembled a carousel installation. The principle of its operation is based on mixing the abrasive medium by the samples being studied with a given speed. Wear resistance was evaluated by weight loss by samples after several test cycles. To determine changes in the structure of the metal during abrasive wear, metallographic studies of the samples were carried out before and after the tests. It is shown that the best complex of service and mechanical properties is possessed by 110G13L steel.

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Evaluation of the Influence of Pre-Alloyed Powder Fe65Nb on the Production of Metal Matrices by Powder Metallurgy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1012.3 ◽

2020 ◽

Vol 1012 ◽

pp. 3-8

Author(s):

A.C.G. Silva ◽

Hellen C.P. Oliveira ◽

Thales Eduardo Leal ◽

Paulo Santos Assis

Keyword(s):

Mechanical Properties ◽

Powder Metallurgy ◽

Chemical Composition ◽

Solid State ◽

Hot Pressing ◽

Physical And Mechanical Properties ◽

Toxic Element ◽

Alloyed Powder ◽

Eds Analysis ◽

Porosity Measurements

The objective of this paper is to study Fe65Nb-Cu metal matrices, thus varying the content of the pre-alloyed Fe65Nb powder from 10% to 100%. Therefore, powders of Fe65Nb and Cu were used, innovating in the chemical composition of the commonly used matrices. The objective is to evaluate the substitution of Co (toxic element, commonly used) by Nb (98.2% of reserves are Brazilian). For the sintering of the samples it was used hot pressing technique. The parameters were set at: 850°C / 35MPa / 3min. The sintered bodies underwent SEM/EDS analysis and density and porosity measurements were performed. From the results it is possible to say that the compositions of (10% and 30% Fe65Nb) presented the best physical and mechanical properties. The relative density decreases for the compositions with 40%, 50% and 60% Fe65Nb is justified by the presence of fragile particles in metal matrices, since they require more energy in order to efficiently transport matter (diffusion) in a solid state.

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THE DEPENDENCE OF THE PHYSICAL MECHANICAL PROPERTIES OF EXPANDED-CLAY LIGHTWEIGHT CONCRETE ON THE COMPOSITION

Mokslas - Lietuvos ateitis ◽

10.3846/mla.2010.111 ◽

2010 ◽

Vol 2 (6) ◽

pp. 50-55

Author(s):

Marija Vaičienė ◽

Jurgita Malaiškienė

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Chemical Composition ◽

Water Absorption ◽

Lightweight Concrete ◽

Physical And Mechanical Properties ◽

Concrete Mixture ◽

Active Filler ◽

Binder Material ◽

Substitute Materials

Binder material is the most expensive raw component of concrete; thus, scientists are looking for cheaper substitute materials. This paper shows that when manufacturing, a part of the binder material of expanded-clay lightweight concrete can be replaced with active filler. The conducted studies show that technogenic – catalyst waste could act as similar filler. The study also includes the dependence of the physical and mechanical properties of expanded-clay lightweight concrete on the concrete mixture and the chemical composition of the samples obtained. Different formation and composition mixtures of expanded-clay lightweight concrete were chosen to determine the properties of physical-mechanical properties such as density, water absorption and compressive strength.

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Joint Effect of Steel Addition and Press-and-Sinter on the Properties of Low-Cost PM Ti Alloys

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.770.248 ◽

2018 ◽

Vol 770 ◽

pp. 248-254

Author(s):

Leandro Bolzoni ◽

Elisa Maria Ruiz-Navas ◽

Elena Gordo

Keyword(s):

Mechanical Properties ◽

Chemical Composition ◽

Biomedical Applications ◽

Low Cost ◽

Physical And Mechanical Properties ◽

Steel Powder ◽

Joint Effect ◽

Ti Alloys ◽

Commercial Steel ◽

Processing Techniques

Cheap alloying elements and creative processing techniques are a way forward to open up more industrial opportunities for Ti in sectors where it is not extensively applied yet, rather than in aerospace and biomedical applications. This study focuses on understanding the joint effect of using a commercial steel powder to add Fe to pure Ti and its processing by press-and-sinter on the behaviour of low-cost PM Ti alloys. It is found that the calibrated addition of steel permits to develop new low-cost Fe-bearing Ti alloys that can satisfactorily be produced using the blending elemental PM approach. Densification of the samples and homogenization of the chemical composition are enhanced by the high diffusivity of Fe. The low-cost α+β alloys reach comparable physical and mechanical properties to those of wrought-equivalent PM Ti alloys, such as Ti-6Al-4V, and are therefore promising candidates for load-bearing lightweight products.

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Influence of Aluminium Content on Behaviour of Magnesium Cast Alloys in Bentonite Sand Mould

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.147-149.764 ◽

2009 ◽

Vol 147-149 ◽

pp. 764-769 ◽

Cited By ~ 14

Author(s):

Leszek Adam Dobrzański ◽

Tomasz Tański

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Chemical Composition ◽

Physical And Mechanical Properties ◽

Aluminium Content ◽

Cast State ◽

Cast Alloys ◽

Cast Magnesium Alloys ◽

Cast Magnesium ◽

Cooling Methods

In this paper there is presented the structure and proprieties of the modeling cast magnesium alloys as cast state and after heat treatment, depending on the cooling medium (furnace, water, air), with different chemical composition. The improvement of the manufacturing technique and chemical composition as well as of heat treatment and cooling methods leads to the development of a material designing process for the optimal physical and mechanical properties of a new developed alloy. In the analysed alloys a structure of solid solution and fragile phase  (Mg17Al12) occurred mainly on grain borders as well as eutectic and AlMnFe, Mg2Si phase. The investigation is carried out to testy the influence of the chemical composition and precipitation processes on the structure and mechanical properties of the magnesium cast alloys with different chemical composition in its as cast alloys and after heat treatment.

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INVESTIGATION OF HOT PLASTIC DEFORMATION OF LABORATORY AXIAL FLOATS

International scientific and technical conference Information technologies in metallurgy and machine building ◽

10.34185/1991-7848.itmm.2021.01.002 ◽

2021 ◽

pp. 12-16

Author(s):

Oleksandr Babachenko ◽

Ganna Kononenko ◽

Katerina Domina ◽

Rostislav Podolskyi ◽

Olena Safronova

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Plastic Deformation ◽

Chemical Composition ◽

Physical And Mechanical Properties ◽

Pressure Treatment ◽

Initial Length ◽

Hot Plastic Deformation ◽

The Impact ◽

Further Development

A review of research in the field of modeling experiments on heat treatment and pressure treatment of metal and the impact on the physical and mechanical properties of steel with a chemical composition of 0.59% C, 0.31% Si, 0.73% Mn. A mathematical model for calculating the physical and mechanical properties of steel in the process of hot plastic deformation has been developed and prospects for further development of research in this area have been identified. As a result of modeling, the following functions were obtained: the amount of deformation in the direction of the applied force divided by the initial length of the material. The coefficient of elongation of the material with the actual chemical composition at a temperature of 1250 ± 10 ° C, which was 0.32. When comparing the values of the load that was applied to the GPA in the laboratory and the results of calculations using the developed model, it was found that they have close values of about 45 MPa. This confirms the adequacy of the obtained model.A review of research in the field of modeling experiments on heat treatment and pressure treatment of metal and the impact on the physical and mechanical properties of steel with a chemical composition of 0.59% C, 0.31% Si, 0.73% Mn. A mathematical model for calculating the physical and mechanical properties of steel in the process of hot plastic deformation has been developed and prospects for further development of research in this area have been identified. As a result of modeling, the following functions were obtained: the amount of deformation in the direction of the applied force divided by the initial length of the material. The coefficient of elongation of the material with the actual chemical composition at a temperature of 1250 ± 10 ° C, which was 0.32. When comparing the values of the load that was applied to the GPA in the laboratory and the results of calculations using the developed model, it was found that they have close values of about 45 MPa. This confirms the adequacy of the obtained model.

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Artificial Thermal Decay: Influence of Mineralogy and Microstructure of Sandstone, Calcarenite and Marble

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/906/1/012123 ◽

2021 ◽

Vol 906 (1) ◽

pp. 012123

Author(s):

Andrea Aquino ◽

Stefano Pagnotta ◽

Marco Lezzerini

Keyword(s):

Mechanical Properties ◽

Thermal Stresses ◽

Construction Materials ◽

Physical And Mechanical Properties ◽

Thermal Decay ◽

Ornamental Stone ◽

Aesthetic Appearance ◽

Ornamental Stones ◽

Before And After ◽

Volume Measurements

Abstract Within a major framework of studies around artificial weathering and its effects on different lithotypes, in this work we study the effects of thermal stresses after artificial thermal decay on different types of stones used in historical buildings: a sandstone, a calcarenite and a marble. The sandstone belongs to the so called “Macigno” Formation and mainly outcrops along the northern Apennine (North Western Tuscany) and it has been widely used around Tuscany for building purposes (e.g., in Florence, Lucca, Pisa, Pistoia, etc.); the analysed calcarenite (Gravina) comes from the surrounding of Matera Town and has been deeply used for the construction of the ancient buildings of the town itself; and the marble comes from the Carrara marble district (Northern Tuscany), a highly used stone throughout the centuries as ornamental stone. All these types of stone for their physical and mechanical properties, and aesthetic appearance, have been extensively used as both ornamental stones and as construction materials. To reproduce a plausible effect of natural thermal decay of the stones due to day-to-night and season-to-season fluctuations, we subjected the samples to artificial thermal decay. We carried out different thermal cycles on the samples by using a stove at 150°C and a muffle furnace at 300°C and 450°C. We analysed the physical and mechanical properties before and after each cycle to compare and evaluate the effects of thermal stresses on the stones. Among the different analyses: mass and volume measurements, water absorption tests, mercury intrusion porosimetry, thin-section observations and determination of chromatic alterations through image analysis and Munsell charts method. It was then possible to evaluate the influence of both mineralogy and microstructures on thermal decay of the studied stones (variations in fabric and modifications on physical and mechanical properties).

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Willow wood (Salix alba) as a raw material for pulp production

Hemijska industrija ◽

10.2298/hemind0508175k ◽

2005 ◽

Vol 59 (7-8) ◽

pp. 175-179

Author(s):

Bojana Klasnja ◽

Sasa Orlovic ◽

Nenad Radosavljevic ◽

Miroslav Markovic

Keyword(s):

Mechanical Properties ◽

Chemical Composition ◽

Populus Deltoides ◽

Chemical Properties ◽

Physical And Mechanical Properties ◽

Raw Material ◽

Poplar Wood ◽

Salix Alba ◽

Pulp Production ◽

Sulphate Pulp

The properties of willow wood (structural-physical and mechanical properties and chemical composition) were investigated to determine the parameters of the technological process of semichemical and sulphate pulp manufacture. The experimental material was willow wood Salix alba cl. 107/65/7. Semichemical and sulphate pulp were obtained in the laboratory. The yield, chemical properties and physical-mechanical properties of the obtained intermediate products intended for paper manufacture, were determined. The properties of poplar wood Populus deltoides Bartr. cl.725, were studied and its pulp production performed with the aim of comparison.

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