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Surface Microhardness and Flexural Strength of Colored Zirconia Liu Qi1,a, Shao Longquan1,b,Wen Ning2 and Deng Bin2 1 Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China 2 Stomatology Center, General Hospital of Chinese PLA, Beijing 100853, China a 170453760@qq.com, bshaolongquan@yaoo.com.cn Keywords: Dental ceramics, Zirconia, Mechanical properties.
The mechanical properties were tested after sintering at 1500°C.
Prolonged the shading time lowered the biaxial flexural strength of zirconia ceramic, but shading time did no effect on surface microhardness.  The most important optical properties of zirconia ceramics are opaque, translucent and the color matching with veneering porcelain.
Table 1 were the mechanical properties of zirconia under different shading conditions and the results of the analysis of variance showed that the difference between the means of the surface microhardness after coloring was not statistically significant (P> 0.05).
The characteristic of phase transformation toughening made the materials to have good mechanical properties [4,5], in which some important indicators included flexural strength and microhardness.

Moreover, bending strength increased up to 9% for hybrid laminates revealing that nanostructures can add functionalities to traditional composite laminates without affecting their mechanical performances.
Different techniques can be used to incorporate interlaminar nanofibers among CFR plies even if porosity can affect the final required mechanical and interlaminar properties.
Diffusion and viscosity are limited by nanofibers and for this reason advantages and disadvantages have to be balanced by the proper design of nano-reinforcements integration to pursue the enhancements of mechanical properties without affecting laminate processing.
Conclusions In the composite manufacturing, material innovations have to improve properties of already high-performance materials without affecting the common industrial practice.
The right addition of nanostructures allows to functionalize traditional composite laminates without affecting, or, in the best case, enhancing mechanical performances.

The fuzzy evaluation model for the affecting factors of highway construction accidents was established.
Then the weight of relative factors were determined.
Unsafe condition Unsafe condition object refers to a substance involved in the production process, the inherent insecurity of these properties and their potentially damaging ability of a substance composed.
A total of four indexes and 15 evaluation factors.
The fuzzy evaluation process is shown in Fig.2 Fuzzy evaluation factors set U The conclusion of evaluation Multi-factors comprehensive fuzzy evaluation Single factor fuzzy evaluation Evaluation set V Fig.2 Fuzzy evaluation process The basic steps of fuzzy evaluation are shown below: (1) Establish fuzzy evaluation factors set U If we want to establish the mathematical model of fuzzy evaluation, the first is to establish factors set, assume the fuzzy evaluation factors set is U.

Since the equivalent strain rate has a great effect of material properties, it is of important to reveal the dependence of the strain rate intensity factor on parameters characterizing material models.
Since the equivalent strain rate significantly influences the evolution of material properties, this theoretical result is in qualitative agreement with many experimental results demonstrating that there is a material layer near friction surfaces within which material properties are quite different from those in the bulk [2 - 8].
Farris, A new approach for studying mechanical properties of thin surface layers affected by manufacturing processes, Trans.
Shikimaka, An approach to prediction of evolution of material properties in the vicinity of frictional interfaces in metal forming, J.
Wang, Interfacial microstructure and mechanical properties of Cu/Al clad sheet fabricated by asymmetric roll bonding and annealing, Mater.

Dynamical mechanical analysis indicates that the loss factor of composite was impaired by the incorporation of acid treated MWCNT.
Polymer/CNT composites possess excellent mechanical properties, thermal stability and electrical conductivity.
The enhancement of these properties mainly derives from the nanometer scale and high aspect ratio of CNT [1].
Damping properties were carried out on a Pyris 7e dynamic mechanical analyzer (PerkinElmer, USA) over a temperature range of 20-160°C at a heating of 5°C / min at 1HZ.
Dynamic mechanical analysis reveals the incorporation of acid treated MWCNT reduced the damping properties of composite.

Through the experiment, we can get and analyze the characteristics of various factors.
Comparatively perfect level with various factors is A3B3C2.
Admixed with fly ash and slag can be formed good mutual filling effect between the cement particles, thereby effectively improving the mechanical properties of concrete [2].
Comparatively perfect level with various factors is A1B2C3.
Effect on the mechanical property of high-strength concrete admixed with fly ash and slag [J].

The aramid paper exhibits numerous excellent properties such as good thermal property, flame resistance, electrical insulation transformer, high dielectric strength, good mechanical properties, and was applied widely in many fields including electrical insulation, aero wing, radome, honeycomb panel, etc [4].
The mechanism properties of aramid paper are showed in Fig. 4.
The dates show that the aramid paper with a better strength and elongation are prepared, and the proportion of fiber/fibrid is the main factor for affecting the mechanism properties of aramid paper.
So, the proportion of fiber/fibrid is very important for endowing the aramid paper with excellent mechanism, the short aramid fiber is the matrix affecting the strength and thermal property and aramid fibrid has excellent adhesive property for binding.
Fig. 4 Mechanical property of aramid paper Mechanism property of aramid/aerogel.

Microstructure and Mechanical Properties of Laser Welded Dual Phase and Mild Steel Joints for Automotive Applications K.M.
The microstructure gives these steels unique mechanical properties, such as high work hardening when compared to those of conventional steels [4, 5].
These thermal cycles produce a microstructure in the weld zone with constituents which affect the mechanical properties of the high-strength steels [8].
The chemical composition and mechanical properties of these steels are summarized in Table 1.
Dong, Microstructure and mechanical properties of laser welded DP600 steel joints, Mater.

Much enhancements on properties of nanocomposite fabricated using bath sonication compared to using high speed mechanical mixing only.
Distribution of nanofillers in the preparation of epoxy/graphene nanocomposites is one of the greatest challenges that affected the final properties of the composites.
Nanocomposite processed by combination method showed more enhancement in flexural strength compared to isolation method due to two factors.
Koratkar, Enhanced mechanical properties of nanocomposites at low graphene content, Small, 6 (2010) 179–183
Goyat, Influence of ultrasonic dual mode mixing on morphology and mechanical properties of ZrO2-epoxy nanocomposite, High Perform.

MECHANICAL PROPERTIES OF ZIRCONIA TOUGHENED ALUMINA COMPOSITES WITH TZP PARTIALLY NANOSTRUCTURED SINTERED BY LIQUID FASE.
In the Table 1, it can observe the values of relative specific mass, linear retraction and porosity and of the mechanical properties of alumina - niobia ceramics and of the composites of ZTA.
Some factors as the solubility decrease of MgO in the net of alumina and as well, the presence of small quantities of niobia up to 5 % in weight in zirconia´s ceramics, contribute for a continuous decrease in the specific mass of the material[12].
These results show that the zirconia acted as an inhibiter of the grains growth in the ceramic composite, but that did not result in a considerable increase in the mechanical properties, mostly when compared to alumina - niobia.
For this striking influence of the vitreous phase and of niobia in the present zirconia in these ceramic composites, it was not possible to relate the effect of the grains size to the mechanical properties of this material.