Study on mechanical properties and fragmentation under detonation loading of different types of tungsten alloys

This study shows the effect of different types of internal curing liquid on the properties of alkali-activated slag (AAS) mortar. NaOH solution and deionized water were used as the liquid internal curing agents and zeolite sand was the internal curing agent that replaced the standard sand at 15% and 30%, respectively. Experiments on the mechanical properties, hydration kinetics, autogenous shrinkage (AS), internal temperature, internal relative humidity, surface electrical resistivity, ultrasonic pulse velocity (UPV), and setting time were performed. The conclusions are as follows: (1) the setting times of AAS mortars with internal curing by water were longer than those of internal curing by NaOH solution. (2) NaOH solution more effectively reduces the AS of AAS mortars than water when used as an internal curing liquid. (3) The cumulative heat of the AAS mortar when using water for internal curing is substantially reduced compared to the control group. (4) For the AAS mortars with NaOH solution as an internal curing liquid, compared with the control specimen, the compressive strength results are increased. However, a decrease in compressive strength values occurs when water is used as an internal curing liquid in the AAS mortar. (5) The UPV decreases as the content of zeolite sand that replaces the standard sand increases. (6) When internal curing is carried out with water as the internal curing liquid, the surface resistivity values of the AAS mortar are higher than when the alkali solution is used as the internal curing liquid. To sum up, both NaOH and deionized water are effective as internal curing liquids, but the NaOH solution shows a better performance in terms of reducing shrinkage and improving mechanical properties than deionized water.

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Investigation of Color Reproduction on Linen Fabrics when Printing with Mimaki TX400-1800D Inkjet with Pigment TP250 Dyes

Coatings ◽

10.3390/coatings11030354 ◽

2021 ◽

Vol 11 (3) ◽

pp. 354

Author(s):

Tim Tofan ◽

Rimantas Stonkus ◽

Raimondas Jasevičius

Keyword(s):

Mechanical Properties ◽

Color Reproduction ◽

Related Effect ◽

Color Characteristics ◽

Fabric Density ◽

Different Types ◽

The Difference ◽

Printing Parameters ◽

Linen Fabric

The aim of this research is to investigate related effect of dyeability to linen textiles related to different printing parameters. The study investigated the change in color characteristics when printing on linen fabrics with an inkjet MIMAKI Tx400-1800D printer with pigmented TP 250 inks. The dependence of color reproduction on linen fabrics on the number of print head passes, number of ink layers to be coated, linen fabric density, and different types of linen fabric was investigated. All this affects the quality of print and its mechanical properties. The change in color characteristics on different types of linen fabrics was determined experimentally. We determine at which print settings the most accurate color reproduction can be achieved on different linen fabrics. The difference between the highest and the lowest possible number of head passages was investigated. The possibilities of reproducing different linen fabric colors were determined.

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Mechanical and Morphological Properties of Bio-Phenolic/Epoxy Polymer Blends

Molecules ◽

10.3390/molecules26040773 ◽

2021 ◽

Vol 26 (4) ◽

pp. 773

Author(s):

Ahmad Safwan Ismail ◽

Mohammad Jawaid ◽

Norul Hisham Hamid ◽

Ridwan Yahaya ◽

Azman Hassan

Keyword(s):

Mechanical Properties ◽

Phase Separation ◽

Polymer Blends ◽

Epoxy Polymer ◽

Flexural Modulus ◽

Polymeric Materials ◽

Morphological Properties ◽

Comparison Results ◽

Unique Material ◽

Different Types

Polymer blends is a well-established and suitable method to produced new polymeric materials as compared to synthesis of a new polymer. The combination of two different types of polymers will produce a new and unique material, which has the attribute of both polymers. The aim of this work is to analyze mechanical and morphological properties of bio-phenolic/epoxy polymer blends to find the best formulation for future study. Bio-phenolic/epoxy polymer blends were fabricated using the hand lay-up method at different loading of bio-phenolic (5 wt%, 10 wt%, 15 wt%, 20 wt%, and 25 wt%) in the epoxy matrix whereas neat bio-phenolic and epoxy samples were also fabricated for comparison. Results indicated that mechanical properties were improved for bio-phenolic/epoxy polymer blends compared to neat epoxy and phenolic. In addition, there is no sign of phase separation in polymer blends. The highest tensile, flexural, and impact strength was shown by P-20(biophenolic-20 wt% and Epoxy-80 wt%) whereas P-25 (biophenolic-25 wt% and Epoxy-75 wt%) has the highest tensile and flexural modulus. Based on the finding, it is concluded that P-20 shows better overall mechanical properties among the polymer blends. Based on this finding, the bio-phenolic/epoxy blend with 20 wt% will be used for further study on flax-reinforced bio-phenolic/epoxy polymer blends.

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The Effect of Water Concentration in Ethyl Alcohol on the Environmentally Assisted Embrittlement of Austempered Ductile Irons

Metals ◽

10.3390/met11010094 ◽

2021 ◽

Vol 11 (1) ◽

pp. 94

Author(s):

Petar Janjatovic ◽

Olivera Eric Cekic ◽

Leposava Sidjanin ◽

Sebastian Balos ◽

Miroslav Dramicanin ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Cast Iron ◽

Ultimate Tensile Strength ◽

Ethyl Alcohol ◽

Water Concentration ◽

Different Types ◽

Influence Of Water ◽

Iron Material ◽

Proof Strength

Austempered ductile iron (ADI) is an advanced cast iron material that has a broad field of application and, among others, it is used in contact and for conveyance of fluids. However, it is noticed that in contact with some fluids, especially water, ADI material becomes brittle. The most significant decrease is established for the elongation. However, the influence of water and the cause of this phenomenon is still not fully understood. For that reason, in this paper, the influence of different water concentrations in ethyl alcohol on the mechanical properties of ADI materials was studied. The test was performed on two different types of ADI materials in 0.2, 4, 10, and 100 vol.% water concentration environments, and in dry condition. It was found that even the smallest concentration of water (0.2 vol.%) causes formation of the embrittled zone at fracture surface. However, not all mechanical properties were affected equally and not all water concentrations have been critical. The highest deterioration was established in the elongation, followed by the ultimate tensile strength, while the proof strength was affected least.

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Approaches to the Mechanical Properties of Threaded Studs Welded to RHS Columns

Materials ◽

10.3390/ma14061429 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1429

Author(s):

Ismael García ◽

Miguel A. Serrano ◽

Carlos López-Colina ◽

Fernando L. Gayarre ◽

Jesús M. Suárez

Keyword(s):

Mechanical Properties ◽

Tensile Tests ◽

Efficient Solutions ◽

Bolted Joints ◽

Building Structures ◽

Static Behavior ◽

Steel Tubes ◽

Punch Test ◽

Different Types ◽

The Face

The use of Rectangular Hollow Sections (RHS) as columns in steel construction includes important advantages like higher mechanical strength and fire resistance. However, the practical demountable bolted joints between beams and columns are not easy to execute, due to impossibility of access to the inner part of the tube. The use of threaded studs welded to the face of the tube and bolted to the beam by means of angle cleats is one of the cheaper and most efficient solutions to obtain beam–column joints with a semi-rigid behavior, as is usually sought in building structures. Nevertheless, it is important to point out that the stud-diameter and the stud-class selection may affect the mechanical properties of the welded parts of the joint. In this paper, 8MnSi7 (with a commercial designation K800) and 4.8 threaded studs were welded to RHS steel tubes and mechanical properties on the weld, the Heat Affected Zones (HAZ), and the base metal were obtained in two different ways: through a correlation with the Vickers hardness and by means of the Small Punch Test (SPT). A study of the microstructure and tensile tests on the threaded studs and in the columns was also carried out. The research involved different types of stud qualities, tube wall thicknesses, and stud diameters. The work presented in this paper proved that in most cases, the welded joint between these studs and the RHS steel tubes present a reasonable static behavior that fulfils the requirements for the beam–column joints under static loading.

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Effect of Nano Clay on Mechanical Behavior of Bamboo Fiber Reinforced Polyester Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.877.294 ◽

2018 ◽

Vol 877 ◽

pp. 294-298 ◽

Cited By ~ 6

Author(s):

Kundan Patel ◽

Jay Patel ◽

Piyush Gohil ◽

Vijaykumar Chaudhary

Keyword(s):

Mechanical Properties ◽

Composite Materials ◽

Clay Content ◽

Weight Fraction ◽

Industrial Applications ◽

Vital Role ◽

Bamboo Fiber ◽

Nano Clay ◽

Different Types ◽

Polyester Composite

Composite materials play a vital role in many industrial applications. Researchers are working on fabrication of new composite materials worldwide to enhance the applicability of these materials. The present study aimed to investigate the effect of Nano clay loading as filler on the mechanical properties of the bamboo fiber yarn reinforced polyester composite. Five different types of composite specimen were prepared with Nano clay loadings of 0 to 4 % weight fraction using hand lay-up technique. It was observed that the composite sheet with 1 wt % nano clay content exhibited the optimized tensile and flexural strength. However the mechanical properties tend to decrease with addition of nano clay content from 2 to 4 wt %. In spite of that the values of mechanical properties with 2 and 3 wt % nano clay content is higher than 0 wt % nano clay content.

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Hierarchical Design and Nanomechanics of the Calcified Byssus of Anomia simplex

MRS Proceedings ◽

10.1557/proc-1187-kk05-09 ◽

2009 ◽

Vol 1187 ◽

Cited By ~ 2

Author(s):

Jakob R Eltzholtz ◽

Marie Krogsgaard ◽

Henrik Birkedal

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Mechanical Performance ◽

Blue Mussel ◽

Hierarchical Design ◽

Reduced Modulus ◽

Different Types ◽

Microscopy Images ◽

Scanning Electron

AbstractBiology has evolved several strategies for attachment of sedentary animals. In the bivalves, byssi abound and the best known example being the protein-based byssus of the blue mussel and other Mytilidae. In contrast the bivalve Anomia sp. has a single calcified thread. The byssus is hierarchical in design and contains several different types of structures as revealed by scanning electron microscopy images. The mechanical properties of the byssus are probed by nanoindentation. It is found that the mineralized part of the byssus is very stiff with a reduced modulus of about 67 GPa and a hardness of ˜3.7 GPa. This corresponds to a modulus roughly 20% smaller than that of pure calcite and a hardness that is about 20% larger than pure calcite. The results reveal the importance of microstructure on mechanical performance.

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Effect of Heat Treatment Process and Composition on Deformation and Damage Behavior of WHA under Detonation Loading

Journal of Physics Conference Series ◽

10.1088/1742-6596/2101/1/012067 ◽

2021 ◽

Vol 2101 (1) ◽

pp. 012067

Author(s):

J J Tang ◽

Z F Liang ◽

X Y Hu

Keyword(s):

Mechanical Properties ◽

Treatment Process ◽

High Strain ◽

Dynamic Mechanical Properties ◽

Damage Effect ◽

Tungsten Heavy Alloy ◽

Damage Behavior ◽

Explosion Test ◽

The Military ◽

Detonation Loading

Abstract The excellent material properties of tungsten heavy alloy (WHA) make it widely used in the military field. When used as killing elements of weapons, its dynamic mechanical properties under detonation loading directly determine the damage effect of weapons, which makes the research on its mechanical behaviors under high pressure and high strain rate loads such as detonation loading of great significance. In this paper, several WHAs with different compositions and processes are selected, and the mechanical properties and deformation and damage behavior under static explosion test are analyzed by combining macro and micro study, so as to provide guidance for the subsequent optimization of the performance design of WHA.

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