Study on Physical and Mechanical Characteristics of Q2 Loess and Micro-Structure Properties in Li-Shan

2014 ◽  
Vol 1065-1069 ◽  
pp. 1846-1849 ◽  
Author(s):  
Ying Wang ◽  
Pan Pan Yang

The physical and mechanical properties and microstructure of Q2loess are of great theoretical and practical significance. Through studying these properties which Q2loess samples are taken in the Xi'an city of Lin-tong District of Mount Li, the results show that: (1)Natural water content, wet density, liquid and solid index, shear strength, collapsible coefficient compressive modulus; (2)By means of the scanning electron microscope to study the picture of the loess micro-structure, there are some preliminary understanding of micro-structure’s basic characteristics; (3)Using scanning electron microscopy techniques to observe the loess micro-structure, As the performance of the loess micro-structure’s basic unit-body and its arrangement form, the loess micro-structure is the reflection of its physical and mechanical properties, Meanwhile the change of physical and mechanical properties also show the unstability of the loess micro-structure.

BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 8291-8302
Author(s):  
Mona Shayestehkia ◽  
Habibollah Khademieslam ◽  
Behzad Bazyar ◽  
Hossein Rangavar ◽  
Hamid Reza Taghiyari

The effects of cellulose nanocrystal (CNC) particles were investigated relative to the physical, mechanical, and microstructural properties of wood cement composite panels. Wood and cement were mixed at three ratios of 1:3, 1:3.5, and 1:4. Calcium chloride was added at 3 and 5%. CNC was added to the mixture at five levels (0, 0.1, 0.2, 0.5, and 1%, based on dry weight of cement). The results showed that CNC content of 0.5% had the best impact on the properties. The overall trend showed that with the addition of CNC, tensile, flexural, and physical properties of the composites were considerably enhanced. Scanning electron microscopy demonstrated that the addition of CNC was associated with an improved integrity in the micro-structure of panels.


2021 ◽  
Vol 899 ◽  
pp. 557-562
Author(s):  
Timur A. Borukaev ◽  
Luiza I. Kitieva ◽  
Abubekir Kh. Shaov ◽  
A.A. Kyarov

Based on magnesium carbonate and antimony oxide (V), MgO•Sb2O5 was obtained. In the formulation of fire-resistant cable PVC-plasticate, antimony (III) oxide was replaced by MgO•Sb2O5 and the fire resistance and physical and mechanical properties of the resulting compound were investigated. It is shown that the replacement of antimony (III) oxide in the composition of PVC cable compound MgO•Sb2O5 leads to the production of a compound that is not inferior in its characteristics to the original plastic compound. In particular, the fire resistance of cable PVC-plasticate, standard industrial formulation and with the obtained MgO•Sb2O5, is practically the same (OI=32%). It has been established that the physical and mechanical characteristics of the cable compound, when replacing antimony oxide (III) with MgO•Sb2O5 in the formulation, remain at the level of the original compound, while MgO×Sb2O5 will have a less negative impact on the environment.


2011 ◽  
Vol 306-307 ◽  
pp. 754-757 ◽  
Author(s):  
Xian Qin Hou ◽  
Jian Ye Liu ◽  
He Yi Ge

The physical and mechanical properties of alumina (Al2O3) ceramics by introduction of zirconia (ZrO2) fiber were studied. ZrO2/Al2O3ceramics at different sintering temperature was investigated by porosity and water absorption measurements, flexual strength and thermal shock resistance analysis. Results showed that Al2O3 ceramics containing 15 wt% ZrO2fiber with sintering temperature of 1650°C exhibited good mechanical properties and thermal shock resistance. The porosity and water absorption were 7.4% and 0.69%, respectively. The flexual strength was 613 MPa and the thermal shock times reached 29 times. Scanning electron microscope (SEM) was used to analyze the microstructure of Al2O3 ceramics.


2013 ◽  
Vol 86 (2) ◽  
pp. 205-217 ◽  
Author(s):  
Hedayatollah Sadeghi Ghari ◽  
Zahra Shakouri

ABSTRACT Research was undertaken on natural rubber (NR) nanocomposites with organoclays. A double-network (DN) structure is formed when a partially cross-linked elastomer is further cross-linked during a state of strain. Two methods were used in the preparation of NR/organoclay nanocomposites: the ordinary method (single-network NR nanocomposite) and double-networked NR (DN-NR) nanocomposites. The single-networked NR nanocomposites were used for comparison. The effects of organoclay (5 phr) with a different extension ratio on curing characteristics, mechanical properties, hardness, swelling behavior, and morphology of single- and double-networked NR nanocomposites were studied. The results showed that double-networked NR nanocomposites exhibited higher physical and mechanical properties. The tensile strength of DN-NR nanocomposites increased up to 33 MPa (more than four times greater than that of pure NR) and then decreased with an increasing extension ratio. Modulus and hardness continuously increased with an increased extension ratio. The microstructure of the NR/organoclay systems was studied by X-ray diffraction and field emission scanning electron microscopy. The effects of different extension ratios on the dispersion of organoclay layers in the nanocomposites were investigated. Generally, results showed that the optimized extension ratio in DN nanocomposites was equal (or about or around) to α= 2.


Clay Minerals ◽  
2011 ◽  
Vol 46 (2) ◽  
pp. 213-223 ◽  
Author(s):  
V. Lilkov ◽  
I. Rostovsky ◽  
O. Petrov

AbstractCement mortars and concretes incorporating clinoptilolite, silica fume and fly ash were investigated for changes in their physical and mechanical properties. It was found that additions of 10% clinoptilolite and 10% Pozzolite (1:1 mixture of silica fume and fly ash) were optimal for improvement of the quality of the hardened products, giving 8% and 13% increases in flexural and compressive strength respectively. The specific pore volume of the mortars incorporating zeolite decreased between the 28th and 180th day to levels below the values for the control composition due to the fact that clinoptilolite exhibits its pozzolanic activity later in the hydration. In these later stages, pores with radii below 500 nm increased at the expense of larger pores. The change in the pore-size distribution between the first and sixth months of hydration occurs mostly in the mortars with added zeolite.


2014 ◽  
Vol 50 (1) ◽  
pp. 87-90 ◽  
Author(s):  
E. Aldirmaz ◽  
I. Aksoy

In this study, some physical and mechanical properties in Cu-9.97%Al-4.62%Mn (wt%) alloy were investigated by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and compression deformation test. Bainite phase were obtained in the samples according to SEM and XRD analyses. Compression stress was applied on the alloy in order to investigate the deformation effect on the bainite phase transformation. On the surface of the Cu-9.97%Al-4.62%Mn alloy after the deformation, both bainite and martensite variants formed.


2020 ◽  
Author(s):  
Maryna Leshchyshyn Mykolaivna ◽  
Svitlana Stepanivna Garkavenko ◽  
Antonina Ivanivna Babich

Determination of values and dependencies of deformation and physical and mechanical properties of materials of shoe models and finished products. According to the results of theoretical, analytical and marketing research, a number of experimental tests of materials have been carried out to prove the practical significance of the work, namely tests for: deformation of the vamp part of the product, uniaxial and biaxial stretching, bending, dry and wet friction, adhesion, elongation and tearing. There has been established the nature of the distribution of the total elongations of the samples of the vamps cut from different areas of the leather, as well as the ability of the leather material to be formed when improving the shape of the product or changing the shape of the shoetree. The processes of deformation of the vamp part of shoe blanks, physical and mechanical properties of different groups of modern materials and values analysis of similarity of their deformation properties have been studied. There has been created a working model-transformer for carrying out preliminary measurement of clients’ feet at the individual order. The expediency of these works has been proved experimentally. A working version of a model-transformer for foot measurements has been made and as a result of the works approbation, a sample of shoes has been made. The ergonomic properties of the manufactured footwear have been improved due to the use of materials with enhanced physical and mechanical properties. The article investigates the deformation of the most vulnerable vamp part of the men's model of a typical model, as well as the physical and mechanical characteristics of leather materials for manufacturing models and shoes of this type. Providing high quality and comfort of footwear, accuracy of parameters selection of foot measurement, zones of beams and achievement of form stability of footwear with a top from genuine leathers has been predicted.


2020 ◽  
Vol 70 (2) ◽  
pp. 167-180
Author(s):  
Vennapusa Vijaya Bhaskar ◽  
Kolla Srinivas ◽  
Devireddy Siva Bhaskara Rao

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.


2018 ◽  
Vol 281 ◽  
pp. 93-98 ◽  
Author(s):  
Lu Wang ◽  
Jian Qiang Bi ◽  
Wei Li Wang ◽  
Xu Xia Hao ◽  
Xi Cheng Gao ◽  
...  

Due to the remarkable physical and mechanical properties of graphene, it is considered to be one of the most promising reinforcements for structural ceramics. In this paper, the composite material is compacted by hot pressing and the effects of mechanical stirring and ultrasonic on dispersion of graphene in alumina matrix were investigated, which was believed to have a great influence on the mechanical properties of the hot-pressed composites. It is found that from Scanning electron microscopy (SEM) observation. Compared with ultrasonic, the composite, in which graphene was dispersed by mechanical stirring, showed higher bending strength (555.1MPaVS432.3MPa) and fracture toughness (4.4MPa·m1/2VS 4.1MPa·m1/2). The result is much more promising to be employed in the designing and processing of graphene composites.


Author(s):  
Mykhailo Petlovanyi ◽  
◽  
Kateryna Sai ◽  

Purpose. Analytical researches of the stress state of the backfilling stopes with different physical and mechanical properties using numerical modeling to determine possible zones of stability losses and predict their failure. Methods. Numerical modeling of the formation of stresses around a high stopes was carried out for the conditions of mining iron ore reserves in the depth intervals of 740-1040 m of the Pivdenno-Bilozerske deposit, where mining operations are actively carried out using the finite element method in the SolidWorks 2016 software package with reliable substantiation of the parameters of the developed geomechanical model. Results. Numerical simulation of the stress state of the backfilling mass are carried out at variable values of the modulus of its elasticity and the mining depth. It was found that with the existing actual physical and mechanical properties of the backfilling mass during the development of the Pivdenno-Bilozerske deposit, the danger of its failure is predicted at depths of more than 890 m. In the center of the filling array, the stress values change linearly, and at the junction of the roof with the side of the backfilled stopes – polynomial. It was found that an increase in the modulus of elasticity of the backfilling mass allows to reduce the compressive stresses only at the junction of the roof with the side of the backfilled stopes to a value of 800 MPa. Scientific novelty. With an increase in the depth of development, despite an increase in the elastic modulus of the fill, the values of stresses increase, which eliminates the need to increase it with a decrease in the mining depth it was found. Practical significance. The results obtained make it possible to correct the technology of formation of a backfilling mass in the primary stopes, taking into account the formation of stresses on its contour and, with an increase in the mining depth, to form a backfilling mass with viscoplastic properties.


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