Search results

Polymer Composites and the Environment Due to exposure to environmental factors like heat, light or chemicals, polymer composites start to lose their properties, they diminish tensile strength, change color, shape and also their molecular weight.
As soon as they are in the environment, polymers are exposed to a variety of chemical and mechanical processes that cause a change in their structure, and the disintegration of polymers into smaller and smaller fragments begins.
The hydrolytic process is affected mainly by the rate of water diffusion of the polymer, by the chemical bond of the material, the levels of cross-links, or the porosity of the material.
Transition metals such as V, Fe, Co, Ni or Cu can and are usually used to accelerate the oxidative degradation process by a factor of approximately 102.
Both macro plastics and micro plastics particles are affecting the environment and some of its effects are not even known [2-5].

Although hard turning has many advantages, if the hard turning parameters are not properly selected, the shape and position precision and surface properties of the workpiece will be seriously affected [4-5].
In the hard turning process, too high spindle speed will make the friction time between the front cutter face and the chip become longer, the shear angle becomes larger, resulting in the machining surface deformation increases, that is, the surface roughness increases; excessive cutting depth increases cutting resistance, affecting the consistency and stability of the workpiece precision after cutting, and having a negative effect on the service lifetime of the tool; cutting speed is the main factor affecting machining efficiency.
Therefore, in order to ensure the final quality of hard turning products, reasonable cutting parameters should be selected based on the above factors.
[3] H, H, DING, L, B, HANG, Y, G, CHEN, Experimental Research of Surface Integrity for Precision Hard Turing Finished Bearing Rings, China Mechanical Engineering, Bearing. (08) (2016) 1066-1071

The deformation of tire tread under load affects the drainage space.
Alternatively, variables and properties of a given cell are purely representative of one phase or a mixture phase, depending on the volume fraction values.
Fig.8 Factors and its effect tendency A plane which is distance ground 4mm is selected as characteristic-plane.
Fig. 10 Sub-hydroplaning model Table.3 The program and results of orthogonal experiment Test Number Test Factors and level Hydrodynamic Pressure /Pa Width(W)/ mm Angle (D)/mm N 1 6 10 3 158883 2 6 20 4 130094 3 6 30 5 104742 4 8 10 4 128091 5 8 20 5 106572 6 8 30 3 136487 7 10 10 5 102319 8 10 20 3 143168 9 10 30 4 105312 Using the data from Table.3 for regression analysis, we get the multivariate linear regression equations between hydrodynamic pressure and the test factors shown in (3)  (3) The regression coefficient for the model is R=0.988, and the standardized coefficient for each test factors were -0.306, -0.304, -0.889 respectively.
Chinese Journal of Mechanical Engineering, 2013, 26(3): 506-511

Cutting tool DCLNR2525M12-M dimensions [8] Name Description Value B Shank width 25.0 mm CSP Coolant supply property 0 GAMO Rake angle orthogonal -6.0 deg H Height of tool holder shank 25.0 mm HAND Direction of cutting Right ICS Insert clamping system D KAPR Tool cutting edge angle 95.0 deg KAPRC Tool Cutting Edge Angle Code L LAMS Inclination angle -6.0 deg LF Functional length 150.00 mm LH Head length 32.0 mm Shanktype Shanktype Square shank Weight Net weight 0.748 kg In the cutting process, the occurrence of vibrations presupposes the existence of two factors: (i) the variable external force, which causes the vibrations, and (ii) the elastic system, which depends both on the elasticity of each separate element and on the stiffness of the whole system: machine-tool – workpiece – tool cutter – jig.
Dismantled tool DCLNR2525M12-M [8] There are also studies that emphasize the factors that affect the behavior of the cutting tool correlated with the surface roughness obtained from the process [5].
It is known that the appearance of vibrations both in the radial and tangential directions as well as the amplitude of the vibrations are determined by the cutting regime ( ap , F, S ), the geometry of the tool ( α , γ , κ ,κ1 , r , λ ) , the wear of the tool on the Aα face, the smoothness of the tool faces, the cutting fluid, the properties physical and mechanical properties of the processed material and the tool material, the rigidity and damping of the technological system.
Although a range of experimental data of the chipping process can be used, such as vibration occurrence, frequency response functions or time domain data or modal data reflecting natural frequencies, mode shapes and damping ratios, these are all the most affected.
[5] Quang Ngoc The Ho, Thanh Trung Do and Pham Son Minh, Studying the Factors Affecting Tool Vibration and Surface Quality during Turning through 3D Cutting Simulation and Machine Learning Model, Micromachines 2023, 14(5), 1025; https://doi.org/10.3390/mi14051025

At present, the builder decides for the final selection of the design (material) solution of a passive house based on mechanical properties of materials, thermal technical properties of materials and cost of materials.
Finally, it often puts great emphasis on energy carriers ensuring the operation of building and affect the need for primary (renewable and non-renewable) energy.
Thermal and technical evaluation The difference of designed thickness of thermal insulation is based on the different properties of the thermal conductivity λ [W / (m·K)].
Table 6: Comparison of properties of variants no. 1 and no. 2 [9] Variant no. 1 Variant no. 2 Used thermal insulation foam glass (530 mm) XPS (220 mm) Temperature conductivity factor λu [W / (m·K) 0.082 0.034 Specific heat capacity (J·kg-1·K-1) 750 1450 Compressive stress at 10% of relative deformation 570 500 Density (kg·m-3) 150 38 Flammability class A1 E Recyclability YES YES Emissions of CO2 / SO2 (kg / kg) 0.431 / 0.00193 4.2 / 0.0155 Conclusion Not only the choice of structural solution is important in the design of a passive house.
Windows in buildings - diagnostics of selected properties after time of using.

Introduction Nickel-based single crystal superalloys are used as gas turbine blade materials for their excellent mechanical properties at high temperatures.
It has been pointed out that the γ/γ′ microstructures substantially affect the mechanical and creep behavior of the superalloys.
Since the microstructure is one of the key factors determining the material properties, it is necessary to study the influences of different γ/γ′ microstructures.
The elastic properties of the two phases are obtained from references [3].
Results and discussion Average creep properties are given as the macro-creep strain evolution with time, see Fig. 2.

Thirdly, tool manufacturing is a factor crucial to microforming processes as it affects the accuracy in shape and movement or control of the forming tools.
Their mechanical properties are listed in Table 1, αh is an inhomogeneity coefficient following statistical distribution shown in Fig. 1 (b).
Mechanical properties of aluminum and tool steel in FEM simulation Materials Density (Mg/m3) Young’s modulus (GPa) Poisson ratio Yield strength (MPa) Tangent modulus(MPa) Al 2.710 69 0.33 138 202×αh Tool Steel 7.8 207 0.292 / / The cylindrical workpiece was less than 2 mm in diameter and the grain size ranged from 25 to 100 μm.
The geometrical parameters a and b are of significance in the CWR process and may determine the final properties of the products.
The initial surface morphologies of workpiece and tool influence friction and deformation, which may affect the final surface topology of micro product to a great extent.

Based on the test of accelerating aging in high solubility, the physical and mechanical performance tests are conducted on GFRP bolts in normal, acid, alkalis and salt conditions, from which the change law of physical and mechanical property can be studied for bolts in different corrosion conditions.
The studies on corrosion of GFRP anchor bolts, however, are fewer at home and abroad and analysis on corrosion factors and mechanism is insufficient[4,16-20].
The deterioration of its mechanical property after corrosion is more complex than that of reinforcement bars.
When considering the factor of corrosion time, see table 4 for data of GFRP bolts’ tensile strength and elastic modulus and see table 5 for data of these when considering the factor of solubility.
Figure 4 Pull-out breaks of test sections after being corroded Table 4 Mechanical property change of corroded GFRP bolts when considering time Test section No.

The Main Factors of Influence Wear Usually, according to wear mechanism and wear system materials and abrasive, material and material between the functions of the division, wear the main types of abrasive wear can be divided into and adhesive wear, erosion wear, fatigue wear and corrosion wear and fretting wear type etc .
The working process of the rotor speed up to 1800 r/min, fall into the material in the moment that is to the rotor are accelerated, and then along the three flow crossing throw into the rotor crushing cavity, in this process, and the material is the continuing, and speed as high as 40 ~ 80 m/s, convection crossing place cast material have continuous head impact, causing the head cast material wear, for the study of the impact of this vertical shaft for crusher, the influence of the main wear head cast material factors mainly in the following aspects: Head Cast Material Characteristics Behind the materials properties of materials head is the important factor of resistance to wear, its hardness is higher, the more good toughness and wear resistance, the better the current production manufacturers are looking for more wear-resisting material to replace the existing materials.
Material properties of The Influence of Material Particle Size Material particle size in 0 ~ 40 mm, different particle size distribution to wear the impact is different, so different particle size distribution to wear the impact is different also.
Vertical shaft impact crusher is mainly used in crushing limestone, only consider final product particle size distribution, the main effect factors is feeding particle size distribution, spindle speed as well as the feeding speed, but in order to make energy efficient configuration, must consider wearing parts wear problems, therefore, should be to meet product particle size distribution of cases, as far as possible to reduce the wear parts.
Mechanical engineering, 2004, (11) : 17-18 [3] YuZhiXin.

HVOF and cold spray can, to a certain extent, reduce the oxide and porosity, but still they can not change the traditional lamellar structure, and eliminating defects seems to be the only way to improve the mechanical properties of their coatings.
This article reports on the stainless 316L stainless steel coatings deposited by air plasma spray (APS) and low pressure plasma spray (LPPS) respectively, and the characterizations and certain properties of lamellar and equiaxed microstructural coatings are both presented for comparison.
This crystalline structure transition is considered to be possibly related with two factors: subtract temperature and thermal gradient.
The vapor phase of the 316L powder heated by the plasma torch may be one of the major factors that led to a uniform equiaxed microstructure of 316L stainless steel coatings.
The vapor phase of the 316L stainless steel powder in the palsma jet may be one of the major factors that form a uniform equiaxed microstructure.