scholarly journals Lime based Dry Mixes with Carbonate Aggregates

2019 ◽  
Vol 8 (11) ◽  
pp. 3289-3292 ◽  
Keyword(s):  
Mechanical Properties ◽  
Quartz Sand ◽  
Carbonate Rocks ◽  
Physical And Mechanical Properties ◽  
Lime Mortar ◽  
Fine Aggregates ◽  
Lime Mortars ◽  
The Matrix ◽  
Optimal Values ◽  
Quarry Dust

The use of carbonate rocks as aggregates for cement concretes and mortars is limited due to their insufficient strength and the threat of corrosion. The use of quarry dust from crushing carbonate rocks are technically and economically feasible in building compositions based on air-hardening lime. The results of the study of the effect of replacing a part of quartz sand in lime mortar by limestone and dolomite fine aggregates on the basic physical and mechanical properties of lime mortars for restoration are presented in the paper. The matrix of planning experiments, which allows increasing the informativity of the research results in order to reduce the number of experiments in the search for optimal values, is proposed. The efficiency of replacement of the quartz sand with quarry dust of carbonate rocks in the production of dry mixes for restoration is shown.

Influence of Structural Characteristics on Concrete Strength under Dynamic Effects

2019 ◽  
Vol 968 ◽  
pp. 368-379
Author(s):  
Andrii A. Plugin ◽  
Olena Palant ◽  
Dmytro Plugin ◽  
Sergii Miroshnichenko
Keyword(s):  
Mechanical Properties ◽  
Crack Resistance ◽  
Structural Characteristics ◽  
Concrete Strength ◽  
Physical And Mechanical Properties ◽  
Dynamic Effects ◽  
Cement Ratio ◽  
Fine Aggregates ◽  
Water To Cement Ratio ◽  
Optimal Values

The article deals with theoretical and experimental research into dependency of crack resistance of concrete under dynamic effects on coefficients of grain separation of coarse and fine aggregates. It was established that these dependencies were of extreme nature. The research yielded the optimal values of coefficients of grain separation of coarse and fine aggregates, cement particles, and also water-to-cement ratio for the materials under study; these factors provided the best physical and mechanical properties of concrete, including its crack resistance under dynamic effects, both impacts and vibrations..

scholarly journals THE INFLUENCE OF DOSAGE AND PRODUCTION PROCESS ON THE PHYSICAL AND MECHANICAL PROPERTIES OF AIR LIME MORTARS

2020 ◽  
Vol XLIV-M-1-2020 ◽  
pp. 351-356
Author(s):  
L. Garijo ◽  
X. X. Zhang ◽  
G. Ruiz ◽  
J. J. Ortega
Keyword(s):  
Mechanical Properties ◽  
Production Process ◽  
Free Water ◽  
Aggregate Size ◽  
Physical And Mechanical Properties ◽  
River Sand ◽  
Curing Conditions ◽  
Factors Affecting ◽  
Lime Mortars ◽  
The Matrix

Abstract. This paper studies the influence of five different factors affecting the dosage and production process of seven types of air lime mortars on their physical and mechanical properties. Such factors comprise the water/lime ratio, the aggregate type and size, the material of the mold and the curing conditions. Moreover, some physical and mechanical properties, not usually measured on air lime mortars, are obtained, such as open porosity, splitting tensile strength, fracture energy and elastic modulus measured through prisms. The results show that under the three different water/lime ratios tested, the material experiences a structural weakening. Ambient curing conditions were more favorable for air lime mortars than high humid ones. Moreover, it is observed that fabrication with wooden molds provided higher mechanical properties as they absorbed the free water, although this effect was probably local. Air lime mortar with an aggregate size of 2 mm had lower consistency in a fresh state as finer sands were more water demanding and the mechanical properties of this mortar were slightly lower than those of mortar with aggregate sizes of 0/4 mm. Furthermore, using limestone aggregates improved the continuity between the lime and the matrix. This fact resulted in higher mechanical properties of the mortars with limestone aggregates in comparison to those with river sand when maintaining the same water/lime ratios. This study can suppose a further step in the improvement of the dosage methodology of air lime mortars.

Physical and Mechanical Properties of Composites with Aluminum Alloy Matrix Designed for Metal Forming

2013 ◽  
Vol 212 ◽  
pp. 59-62 ◽  
Author(s):  
Jerzy Myalski ◽  
Jakub Wieczorek ◽  
Adam Płachta
Keyword(s):  
Mechanical Properties ◽  
Metal Forming ◽  
Matrix Material ◽  
Physical And Mechanical Properties ◽  
Mechanical Mixing ◽  
Alloy Matrix ◽  
Segregation Process ◽  
The Matrix ◽  
Glass Carbon ◽  
Properties Of Composites

The change of matrix and usage of the aluminum alloys designed for the metal forming in making the composite suspension allows to extend the processing possibility of this type of materials. The possibility of the metal forming of the composites obtained by mechanical mixing will extend the range of composite materials usage. Applying of the metal forming e.g. matrix forging, embossing, pressing or rolling, will allow to remove the incoherence of the structure created while casting and removing casting failures. In order to avoid the appearance of the casting failures the homogenization conditions need to be changed. Inserting the particles into the matrix influences on the shortening of the composite solidification. The type of the applied particles influenced the sedimentation process and reinforcement agglomeration in the structure of the composite. Opposite to the composites reinforced with one-phase particles applying the fasess mixture (glassy carbon and silicon carbide) triggered significant limitation in the segregation process while casting solidification. Inserting the particles into the AW-AlCu2SiMn matrix lowers the mechanical properties tension and impact value strength. The most beneficial mechanical properties were gained in case of heterofasess composites reinforced with the particle mixture of SiC and glass carbon. The chemical composition of the matrix material (AW-AlCu2SiMn) allows to increase additionally mechanical characteristics by the precipitation hardening reached through heat casting forming.

METAL COMPOSITE MATERIALS BASED ON TITANIUM ALLOYS, REINFORCED WITH REFRACTORY PARTICLES (review)

2021 ◽  
pp. 36-45
Author(s):  
E.I. Krasnov ◽  
◽  
V.M. Serpova ◽  
L.G. Khodykin ◽  
A.V. Gololobov ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Composite Materials ◽  
Literature Review ◽  
Titanium Alloys ◽  
Chemical Nature ◽  
Physical And Mechanical Properties ◽  
Metal Composite ◽  
The Matrix ◽  
Metal Composite Materials

Presents a literature review in the field of methods for strengthening titanium and its alloys by introducing various refractory particles into the matrix. The main problematic issues related to the chemical nature of refractory particles and titanium alloys that arise during hardening are briefly described. The main structural, physical and mechanical properties and morphology of such metal composite materials are described. The dependence of the influence of various refractory particles and their amount, as well as the effect of heat treatment on the physical and mechanical properties of microns based on titanium alloys, is presented.

scholarly journals Physical and Mechanical Properties Evaluation of Particle Board Produced from Saw Dust and Plastic Waste

2018 ◽  
Vol 40 ◽  
pp. 1-8 ◽  
Author(s):  
Atoyebi Olumoyewa Dotun ◽  
Adeolu Adesoji Adediran ◽  
Adisa Cephas Oluwatimilehin
Keyword(s):  
Mechanical Properties ◽  
Physical Properties ◽  
Weight Ratio ◽  
Physical And Mechanical Properties ◽  
Modulus Of Rupture ◽  
Maximum Point ◽  
Mixing Ratios ◽  
Saw Dust ◽  
Three Phase ◽  
The Matrix

The current work reports on the fabrication of composite matrix from saw dust (SD) and recycled polyethylene terephthalate (PET) at different weight ratio by flat-pressed method. Wood plastic composites (WPCs) were made with a thickness of 15 mm after mixing the saw dust and PET followed by a three phase press cycle. Physical properties (Density, Water Absorption (WA) and Thickness Swelling (TS)) and Mechanical properties (Modulus of Elasticity (MOE) and Modulus of Rupture (MOR)) were determined base on the mixing ratios according to the standard. WA and TS were measured after 2 h and 24 h of immersion in water. The results showed that as the density increased, the SD content decreased from 90 % to 50 % into the matrix. However, WA and TS decreases when the PET content increased in the matrix. Remarkably, the MOE and MOR attained a maximum point at 964.199 N/mm2and 9.03 N/mm2respectively in 50 % SD content. In comparism with standard, boards D and E can be classified as medium density boards while A, B and C are low density boards. The results indicated that the fabrication of WPCs from sawdust and PET would technically be feasible for indoor uses in building due to favorable physical properties exhibited. The mechanical properties response showed that it cannot be used for structural or load bearing application.

Effect of the Matrix and Reinforcement Sizes on the Microstructure, the Physical and Mechanical Properties of Al-SiC Composites

2016 ◽  
Vol 139 (1) ◽  
Author(s):  
M. A. Salem ◽  
I. G. El-Batanony ◽  
M. Ghanem ◽  
Mohamed Ibrahim Abd ElAal
Keyword(s):  
Mechanical Properties ◽  
Powder Metallurgy ◽  
Volume Fraction ◽  
Physical And Mechanical Properties ◽  
Particle Sizes ◽  
Matrix Composites ◽  
Volume Fractions ◽  
The Matrix ◽  
Sic Composites ◽  
Sic Particle

Different Al-SiC metal matrix composites (MMCs) with a different matrix, reinforcement sizes, and volume fractions were fabricated using ball milling (BM) and powder metallurgy (PM) techniques. Al and Al-SiC composites with different volume fractions were milled for 120 h. Then, the Al and Al-SiC composites were pressed under 125 MPa and finally sintered at 450 °C. Moreover, microsize and combination between micro and nano sizes Al-SiC samples were prepared by the same way. The effect of the Al matrix, SiC reinforcement sizes and the SiC volume fraction on the microstructure evolution, physical and mechanical properties of the produced composites was investigated. The BM and powder metallurgy techniques followed by sintering produce fully dense Al-SiC composite samples with different matrix and reinforcement sizes. The SiC particle size was observed to have a higher effect on the thermal conductivity, electrical resistivity, and microhardness of the produced composites than that of the SiC volume fraction. The decreasing of the Al and SiC particle sizes and increasing of the SiC volume fraction deteriorate the physical properties. On the other hand, the microhardness was enhanced with the decreasing of the Al, SiC particle sizes and the increasing of the SiC volume fraction.

Microstructural Evaluation of Semi-Solid and Thixoformed Parts of LM28 Aluminum Alloy

2012 ◽  
Vol 192-193 ◽  
pp. 136-141
Author(s):  
S.G. Shabestari ◽  
P. Ghaemmaghami ◽  
H. Saghafian ◽  
A. Osanlo
Keyword(s):  
Mechanical Properties ◽  
Morphological Changes ◽  
Physical And Mechanical Properties ◽  
Primary Silicon ◽  
Optical Microscope ◽  
Globular Structure ◽  
Cooling Slope ◽  
The Matrix ◽  
Semi Solid ◽  
Cooling Slope Casting

Attractive physical and mechanical properties of aluminum alloys make them very interesting for the automotive industry. The commercial way for manufacturing LM28 alloy is die-casting, but this process encounters several problems such as shrinkage and gas porosities. Their good mechanical properties and high resistance to wear are because of the presence of hard primary silicon particles distributed in the matrix. Therefore, the size and morphology of primary silicon and also the structure of α-Al particles in hypereutectic Al–Si alloys influence the mechanical properties of the alloys. In this research, a new process of manufacturing of this alloy has been developed using LM28 feedstock produced through cooling slope casting. The feedstocks produced via cooling slope casting had a partial globular structure that contained globules, rosettes and dendrites of α-Al. These feedstocks were thixoformed under three different pressures. The primary dendrites and rosettes changed to globular structure. The microstructure of thixoformed parts contained α-Al globules, small primary Si particles dispersed between these globules, and Al-Si eutectic phase. The mechanism of the formation of α-Al globules by this process was explained. Microstructures of as cast specimens, feedstocks produced via cooling slope, specimens that were heat treated in the semi-solid temperature and thixoformed specimens were studied with optical microscope and image analysis. The morphological changes during these processes were interpreted.

scholarly journals Investigation on Physical and Mechanical Properties of Banana and Palmyra Fiber Reinforced Epoxy Composites

2020 ◽  
Vol 70 (2) ◽  
pp. 167-180
Author(s):  
Vennapusa Vijaya Bhaskar ◽  
Kolla Srinivas ◽  
Devireddy Siva Bhaskara Rao
Keyword(s):  
Mechanical Properties ◽  
Hybrid Composites ◽  
Matrix Material ◽  
Weight Ratio ◽  
Physical And Mechanical Properties ◽  
Epoxy Composites ◽  
Fiber Reinforced ◽  
Micro Structure ◽  
Interfacial Analysis ◽  
The Matrix

AbstractThe present work addresses the physical and mechanical properties of banana and palmyra fiber reinforced epoxy composites with the aim of study on the effect of weight ratio and fiber percentage. The banana and palmyra fibers were arranged with different weight ratios (1:1, 1:3, and 3:1) and then mixed with the epoxy matrix by hand lay-up technique to prepare the hybrid composites with various fiber percentages (10%, 20%, 30% and 40%). The properties are measured by testing its density, water absorption, tensile strength, impact strength, hardness and flexural strength and compared. From the results, it was indicated that addition of banana and palmyra fiber in to the matrix material up to 30% by fiber percentage results in increasing the mechanical properties and slightly variation with weight ratios. Interfacial analysis of the hybrid composites were also observed by using scanning electron microscope (SEM) to study the internal failures and micro structure of the tested specimen.

Sign in / Sign up

Export Citation Format

Share Document