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Meanwhile, the billet tended to stick to the mold wall due to several factors, such as too low a pouring temperature, a less-round mold shape, the poor quality of the hot top and graphite ring, and the water that entered the mold during the casting process.
This casting defect is affected by the inner surface quality of the ring mold and the mold wall.
Surface unevenness and other defects can be caused by factors such as changes in the head of the metal in the mold, differential heat transfer around the mold's periphery due to variations in lubricant thickness or lubricity, or sudden change in the flow speed or discharge angle of the metal stream exiting the mold.
References [1] Silva M S, Barbosa C, Acselrad O and Pereira L C 2004 Effect of chemical composition variation on microstructure and mechanical properties of a 6060 aluminum alloy J.
Sci. 36 1965–76 [13] Wang R, Zuo Y, Zhu Q, Liu X and Wang J 2022 Effect of temperature field on the porosity and mechanical properties of 2024 aluminum alloy prepared by direct chill casting with melt shearing J.

Results reveal that segmental dynamics of NR is affected by uniaxial stretching since a slowing down of the segmental relaxation is achieved.
Thus, a study on how the strain-induced crystallization affects the dynamics of a rubbery material is of outmost importance.
The molecular chains, which are initially entangled, are rearranged along the draw axes, and hence, the polymer shows anisotropic physical properties.
This study has allowed us to know the effects of the strain-induced crystallization on the molecular dynamics of NR, and to understand the improved mechanical properties of the system.
Sweeney: An Introduction to the Mechanical Properties of Solid Polymers (John Wiley & Sons, West Sussex 2004)

The curriculum task requirements: master through the basics of learning materials commonly used material properties, use and test detection skills, in order to work in the rational selection and use of materials.
This question requires an understanding of the relationship between the characteristics of the structural hierarchy and material properties, and focus on understanding the impact of material porosity and its corresponding materials.
The physical state characteristics indicates that the material properties (including the density, bulk density, apparent density, porosity and the physical properties of the material should be focused, as well as a bulk density and porosity of the particulate material), and with water, the heat-related properties (including probate-based and water-repellent, water absorption, water resistance, frost resistance and thermal conductivity).
(2) Due to the wide variety of building materials, with different properties, project cost, the selection of materials to pay attention to the following performance requirements: production, construction, performance and recycling performance: whether the rich resources of raw materials, production, transportation and construction process consumes too many resources pollution of the environment and energy, whether, workability, construction and cycle available; mechanical properties: strength, hardness, rigidity, strong modulus, creep, toughness, fatigue resistance; physical properties: density, deformation capacity particle size; durability: weathering, damage, impermeability, etc.; chemical properties: acid, alkali.
Factors affecting factors: the structural characteristics of the material, strength, moisture content and degree.

If there are any shrinkage cavities, mechanical properties and air tightness of casting will decrease significantly.
The factor is a term which affects the results.
(2) The selection of experimental factors: the main factors considered were as follows: influential factors of Shrinkage Cavity and Porosity, influential factors of technological yield .The experimental factors selected as riser style(A), riser section(B), riser height(C), chill section(D), chill thickness(E).
According to the principle of Orthogonal Array, orthogonal table is selected by the number of factors, the level of factors and experimental purposes.
Fig.5 Trends of factors’ influences on volume of riser Table4 shows the influence of different factors on each indicator from the most to the least and the optimum level according to the range of different factors.

These improved properties by the addition of Nb are brought about by the grain refinement of ferrite matrix and finer dispersion of martensite.
Results and Discussions Mechanical Properties of GA Simulated Steels.
The mechanical properties of the GA simulation steels annealed at 850 o C and 900 oC are shown in Fig.2.
The metallurgical factors affecting on stretch flangeability were discussed mainly for hot rolled steel sheets.
Figure 5 shows the mechanical properties of GA steel after 8% strain and aging at 100oC for 60 min, which is more severe conditions than natural aging.

These effect leads to the degradation of the fiber-matrix interface region resulting in a low transfer of stress between these materials that result in a decrease of the mechanical properties [3-5].
This factor is one of the main drawbacks of these materials.
Baley, Study of tensile properties of stinging nettle fibers (Urticadioica), Mater.
Karlsson, Comparasion of water absorption in natural cellulosic fibers from wood and one-year crops in polypropylene composites and its influence on their mechanical properties, Compos. part A: App.
Li, Relation of modification and tensile properties of sisal fiber, Acta Sci Nat Uni Sunyatseni. 35 (1996) 53-7

The quantification of this defect is difficult, and there are different factors for its determination, such as the conventional delamination factor "FD" the equivalent delamination factor "Fed" and the alternative delamination factor "FA" [10,11].
In summary, the research exposes the relationship that exists between quality, delamination, force, and wear, but few studies correlate these factors.
Results of CFRP material properties Interlaminar shear Tensile strength Elastic Module Glass transition temperature 77 MPa 1072 Mpa 62 GPa 167.54 °C Table 3.
a) b) Figure 2. a) Mahr Perthometer PGK 120 roughness tester with detail of MFW-250 contact stylus b) Three point internal micrometer The delamination factor is a parameter of special importance, as it directly affects the functional performance and mechanical properties of the material components.
The dimensional quality is another relevant factors, where tolerances between 30 and 90 µm are established.

Moreover, the relationship between structure and properties and application of PUA core-shell hybrid emulsion in inks are also put forward in detail.
On the contrary, PA resins possess superior wearing resistance, adjustable mechanical properties and low cost[1-2].
Therefore, it is necessary that the combination of PU and PA resins to achieve excellent properties of hybrid emulsions.
PUA Core-Shell Emulsion Polymerization The forming course of core-shell hybrid emulsions that involve the preparation of PU dispersion and pre-emulsification of monomer, is affected by many factors such as reaction time, temperature, monomer content, initiator concentration etc.
G.Q.Fei et al.[12]discussed the modification of PUA hybrid emulsion with epoxy via in situ surfactant-Free polymerization and studied the mechanical and cohesive properties along with the content variation of E-44.

Thick crescent iced sub-conductors spacing influence on the aerodynamic properties Li-jun MA1, a, Shu-ying HAO1, b and Qi-chang ZHANG2, c 1Tianjin Key Laboratory for Control Theory & Applications in Complicated Systems, Tianjin University of Technology, Tianjin 300384, China; 2School of Mechanical Engineering, Tianjin University, Tianjin 300072, China a41612519@qq.com, bsyhao@tju.edu.cn, cqzhang@tju.edu.cn Keywords: FLUENT, iced conductors, aerodynamic coefficient, wake flow, sub-conductors spacing.
Studies show that aerodynamic coefficient of downwind sub-conductors affected by wake-flow, with the upwind sub-conductors there is always a big difference.
However, because the wind tunnel test is expensive, it can be instead of numerical simulation research the aerodynamic properties of iced conductors.
Fig. 1 Sub-conductors layout Fig. 2 Whole grid of attack angle 45 degree Meshing is the basis for solving the equation, the quality of the mesh will directly affect the accuracy of the results.
Wake’s cause and mechanism In velocity field, the component of conductor drag is the differential pressure from front and behind of the conductor and viscous force, differential pressure is the main factor affecting the aerodynamic drag because of air viscosity is very small.

Besides, the bonding strength of interface between steel fiber and concrete is the main factor that affect the performance of asphalt concrete.
The analysis of the formation mechanism strength of steel fiber asphalt concrete Steel fiber asphalt mixture is a composite material composed of asphalt, aggregate,steel fiber,its strength is derived from the cohesive force and the friction of the aggregate and the pulling force of asphalt fiber.For ordinary asphalt concrete,the mechanical properties of the mixture is mainly borne by the asphalt and aggregate,in the case of tension the tensile properties of asphalt and aggregates are small,it will sudden destruction if beyond the tolerance range.But for steel fiber asphalt mixture,the tensile stress can undertake by asphalt, aggregate and steel fiber.When asphalt tensile damage,it can also rely on the cohesive force between the fiber and asphalt to pass tensile steel fiber.Because the destruction of the ordinary steel fiber reinforced concrete is mainly due to steel fiber’s pull out not by pull off,so the tensile strength of steel fiber can satisfy the use requirement in general while
its bond strength with concrete substrate interface is the main factor affecting the performance of steel fiber reinforced concrete.So the steel fiber reinforced concrete can alleviate the cracking of concrete and increase its service life.
[4] LI Wenying ,HAN Liu, GUAN Ningfeng, study of fiber affect on the properties of asphalt concrete[J].Liao ning Science and Technology of Communication, 2004(2): 14-16
[5] JIANG Jian ,PAN Hongyang,WANG Bing .Study on the anti-seismic properties of fiber reinforcement asphalt concrete[J].China and Foreign Hinghway , 2004 , 24(5) :111-112