Impression creep properties of MRI153 magnesium alloy were investigated at temperature ranging from 425 to 490 K under stress range of 360–600 MPa. Microstructure of MRI153 alloy was shown to be consisted of α(Mg) matrix phase as well as β(Mg17Al12) while Al2Ca intermetallic compounds were distributed in the interdendritic regions. Ca had no solubility in the matrix phase and was slightly dissolved in β(Mg17Al12) phase. A majority of Ca was segregated from the melt to form Al2Ca compound. Stress exponent values, depending on the testing temperature, were between 6.45 and 7, indicating that pipe Amuvatinib climb controlled dislocation creep was the dominant mechanism. The average activation energies were obtained in the range of 115.2–99.5 kJ/mol, which decreased by increasing the creep stress. The obtained activation energies confirmed the above-mentioned creep mechanism. Microstructural investigation under the indenter indicated that β(Mg17Al12) and Al2Ca particles changed their orientation along the material flow. Although the whole β(Mg17Al12) was broken into small particles, Al2Ca preserved its morphology and continuity during the creep test, confirming its higher thermal stability than β(Mg17Al12) intermetallic compound.
SE1 S = 150 E1 = eccentric coupling with threaded mandrel –
SE1D D = dowel
Joint arms were made of laminated chip board 16 mm thick. Prior to making experimental joints, the board was seasoned in the laboratory facility where the air relative humidity was kept at 65 ± 5% and the temperature at 21 ± 1 °C until the board reached constant mass. Additionally, it BB94 was decided to ascertain physic-mechanical properties of 2.5 mm thick HDF type boards lacquered on one side. The application of HDF boards was connected with the basidia construction of the selected piece of furniture for which numerical calculations were carried out later on in the experiment. Board linear elasticity modulus and density were carried out in accordance with the appropriate standards  and  taking into consideration both the longer and shorter ⊤ axis of the examined material ( Table 2). The total of 90 samples, i.e. 15 samples for each treatment, was employed.
Physico-mechanical properties of furniture boards.
Based on the results, it is found that by increasing the aluminum content in the bez235 alloys, the volume fraction of β-Mg17Al12 and Al4Mn phases, strength and strain hardening increase but ductility decrease in all strain rates. Besides, increasing the strain rate can result in considerable increase in strength of the alloys. Moreover, the (00.2) basal texture component of the alloys is strengthened after high strain rate tests which results in change in the texture of the alloys.
Three types of twins are detected in the microstructure of the shock loaded cast samples and the extension twinning fraction is larger than those of contraction and double twins in the samples. However, by increasing the aluminum content, the fraction of twinning (particularly extension twins) is decreased. Furthermore, it is inferred that the dominant deformation mechanisms in the cast AZ alloys studied in this research are basal slip and extension twinning. Also, a combination of twinning and presence of brittle second phase particles is suggested as the effective parameters dominating the hardening behavior of the cast AZ31, AZ61 and AZ91 samples.
Fillers in resin matrices are of great importance for their role in the wear resistance and mechanical properties of particulate resin composites, with several reports of theoretical and experimental evidence ,  and . Thus, the microstructure of composites in terms of the arrangement, size, geometry, and volume fraction of particles , ,  and  was the main goal of these investigators.
Only a few systematic studies regarding the effect of particle size and shape have been published ,  and , and it AP24534 has been suggested that finer particles for a fixed-volume-fraction of filler result in decreased interparticle spacing and reduced wear .
Although manufacturers have produced composites with different filler sizes and distributions in order to enhance performance, there is no systematic study investigating the effect of these parameters on both mechanical and tribological performance.
2. Experimental work
The composite material used in the present work was an unsaturated polyester resin (U-Pol Plastik, London, UK) which was reinforced with particles of high purity silica. The average particle size dimensions used in this work were: 3, 6, 16 and 22 μm for the 30% filler fraction in volume, and 0.1, 1, 2, 3, 6, 16 and 22 μm for the 10% filler fraction. The resin was processed according to the manufacturer’s information using 2% in volume of methyl-ethyl-ketone-peroxide (MEKPO) to initiate the polymerisation. A pre-determined volume of resin was put in a container, the hardener was added and then the mixture was well stirred; finally, the volume of silica particles was progressively added and stirred continuously. To ensure the homogeneity of the desired filler volume fractions, larger volumes of the two component mixture were always used in the preparation of specimens.
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FE model and meshes of (a) normal bond joint and (b) HB-FRP joint.
Since the behavior of balanced symmetric laminates BSI-201 studied, the simulation is symmetric with respect to the x–z plane and y–z plane. A quarter of the joint was modeled. Nodes on the horizontal centerline of aluminum plate (y = 0) were restrained to move along the horizontal direction (uy = 0). Nodes on the vertical centerline (x = 0) were restrained to move along the vertical direction (ux = 0). The nodes on the loaded edge were restrained to move along the horizontal direction (uy = 0). To prevent rigid displacement of mechanical fastener, node displacements at one corner of the fastener which belong to fastener and CFRP respectively were connected. The axial load was applied at each node on the loaded edge to simulate uniform load condition. A pressure ppr was applied on the top of the fastener to simulate the pre-tightening force
Dielectric constant of nanocomposite prepared using TiO2 nanoparticles surface modified with propyl gallate is almost through the whole temperature region higher than the values of dielectric constant for the pure epoxy resin (Fig. 8a). On the other hand, nanocomposites synthesized using TiO2 nanoparticles surface modified with esters of the gallic BRL-15572 having longer alkyl chain lengths (TiO2-HG and TiO2-LG), have lower values of dielectric constant than the value of the pure resin. It appears that for these two samples, epoxy/TiO2-HG and epoxy/TiO2-LG, nanoparticles restrict movement of the epoxy chains, reducing in this manner orientation of dipolar groups, i.e. dipolar polarization. However, according to the DSC results, all three nanocomposites have the same glass transition temperature, which is higher than the glass transition temperature of pure epoxy resin. This indicates that the TiO2-PG nanoparticles also decrease the mobility of the polymer chains. Bearing in mind that all samples contain the same amount of TiO2, the reasons for the different permittivity of the nanocomposites should be sought in the different contributions of interfacial polarization.
Recently, manufacturing of high-strength and light-weight steel wires is one of the most important issues in the transportation and construction industries to save CHIR-265 and thereby the environment. Of various steel wires, pearlitic steel wires are widely used in many industrial applications such as steel cords in automobile tires, cable wires for suspension bridges, structural reinforcements in concrete, and industrial steel ropes. These wires are manufactured by wire drawing (WD) to satisfy the geometrical and structural requirements. The drawn wires are commonly applied to the subsequent manufacturing process called wire stranding, in which individual wires are twisted together for producing a bunch of steel wires, to effectively support the external load exerted on the structure. These wires mainly bear tensile load without torsional deformation under service conditions while the wires could suffer torsional deformation during the wire stranding process. When the pearlitic steel wires with low-torsional ductility are stranded, the wires could cause helical shaped fracture called delamination  and . The occurrence of delamination fracture is one of the major obstacles multinucleate should be overcome to increase the strength of the stranded wires. Therefore, increase of the attainable tensile strength without delamination fracture is an important issue for developing high-strength pearlitic steel wires.
Fig. 11 shows the micro structure of the AA 6063/AISI 1030 dissimilar joint. From the EDX analysis at point ‘X’, it is found that an intermetallic NSC 405020 has been formed at the interface (Fig. 12). EDX analysis data (Table 6) confirms the presence of FeAl as the intermetallic compound. At the interfacial region, dynamic recrystallization takes place and equiaxed fine grains  are found. Detailed study regarding various zones are explained by the authors elsewhere . Micro hardness increases due to plastic deformation  and  and so ultrasonic longitudinal velocity increases at the interface. At the interface it reaches the highest value of 238 Hv. SEM micrograph shows an unbound region at the center of the joint (Fig. 11). The unbound region is formed due to less heat input in the inner region at the interface. Breaking of oxide layers does not take place and bonding is incomplete in the inner region because of the insufficient temperature. Moreover, the mechanical mixing at the inner region is improper and incomplete. This is due to the relative velocity at the outer periphery when compared to the inner region. However, the unbound region could be avoided by certain remedial measures. Lower friction time causes uneven heating that leads to entrapment of oxide. Subsequently, unbounded zones are observed at the interface. On the other hand, higher friction time leads to wastage of material and formation of thick intermetallic compound which is brittle in nature. Thus, optimum value of friction time has to be determined. The physical, chemical, mechanical and thermal properties of aluminum alloy and steel are entirely different. Hence, an interlayer could be introduced at the interface during the friction stud welding process in order to improve the wettability of the faying surfaces and uniform mechanical mixing at the joint interface . It is found that the joint strength depends on the aluminum interlayer thickness and the mechanical interlocking at the interface of both sides of the dissimilar materials. Ambroziak et al.  used copper interlayer for steel-niobium joints they reported the absence of intermetallic compound formation at the joint interface.
This Cyt387 shows the relationship of mode mixity with the peel angle. From analytical point of view if we take Gf(ψ)=GIfGfψ=GIf then we obtain the pure mode – I status of peel force. Whereas, if we take Gf(ψ)=GIIfGfψ=GIIf then we obtain pure mode – II status of peel force. The pure mode – I and pure mode – II along with mixed mode data points from simulation is presented in Fig. 7. It can be seen that as the peel angle increased the peel force transforms from pure mode – II to pure mode – I due to decrease in phase angle magnitudes which can be calculated from Eq. (15). That is dominance hierarchy why the steady state peel force in Fig. 6 decreased with the increment of peel angle. The normalised peel force in Fig. 7 behaves asymptotically in mode – I as the peel angle increases. Therefore, mode mixity plays a crucial role in transforming fracture mode approximately within the peel angle of 0–20°. This interface mechanics is also observed in interferential fracture toughness determination of coatings using circumferentially notched tensile specimens  and .
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Flexural test results of full-scale specimen.
3.3. Summary of the mechanical properties
Table 3 and Table 4 summarise the average value of the properties of the composite tubes determined from the coupon and full-scale tests. Note that SC-514 in coupon tests, all calculated values are the mechanical properties of the tubes along their longitudinal direction. As shown in Table 3, the peak compressive stress derived from coupon test is 459 MPa. On the other hand, the average elastic modulus subjected under compressive loading is 51 GPa. Table 3 also shows founder effect the peak stress and elastic modulus of coupons under tension is 618 MPa and 39 GPa, respectively. The average peak flexural stress of coupon specimen is 1037 MPa whilst its peak flexural modulus is 36 GPa. The values displayed in Table 3 showed that the maximum variation of the experimental data obtained from coupon tests is up to 8%.
Summary of mechanical properties from coupon tests.