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., R & D Center, Çayırova, Gebze, Kocaeli, Turkey Keywords: Hydroxyapatite, sintering, compacts, mechanical properties Abstract.
Hydroxyapatite (HA) is a particularly attractive material for bone and tooth implants because of its chemical and crystallographic properties, which closely resemble those of bone and tooth minerals.
The present study was conducted to examine the influence of sintering temperature on the mechanical properties of the pure HA compacts.
Contrary to the above case, the factor of the sintering temperature has a significant effect on microhardness (F = 18.03 p-value = 0.009).
Summary Density determination, microhardness and compression tests were carried out for synthetic HA to see the main changes in the mechanical properties and it is planned to use these data as reference measurements for future sintered HA studies.

The ductility of Mg-based alloys is strongly affected by two main factors.
This affected a significant increase in the yield point of the alloy.
The specimens with the fine grain size of 2.2µm showed some variability in properties, having tensile strength measurements of between 300 and 325MPa.
It is clear that the processing carried out here has moved the properties of the as-received AZ31 plate into a new property space on this plot.
This does not significantly affect the ductility

Moreover, the factors that affect center tower stiffness are determined.
This will lead to excessive girder deflection, affecting the usability of structure, and tower body to bear shear and bending moment.
With regard to multilane, lateral reduction factor is 0.55.
Four major factors must be considered, they are vertical displacement of girder, horizontal displacement and main cable anti-slides safety coefficient at the top of center tower, along with the maximum bending moment at the root of center tower.
While the maximum bending moment at the root of center tower have a trend of increasing, developing toward a direction that is adverse to structural mechanical property.

It was shown that properties of these implants might be substantially improved with functionally graded materials (FGM).
Different examples are shown and influence of the sintering and gradient profile selection on final properties is discussed.
Existing solutions of materials combinations are not very satisfactory due resulting to wear debris causing complications and low level of mechanical properties in the case of ceramics.
In order to provide superior mechanical, good wear resistance and biological properties in vivo, the functionally graded materials concept can be introduced in to the hip joints design [4].
This was one of the factors of FGM design - to introduce an engineering compressive stress to alumina at the surface of balls and liners.

Results show that the buoyancy caused by grouting pressure is the dominating factor to bring about segments uplift, thus the relationship between the soil properties and the anti-uplift characteristics, the relation curves of soil modulus and the maximum amount of floating upward are deduced [1].
Analyze the factors affecting the uplift of shield tunnel lining through finite element method(FEM), such as the physic-mechanical properties of stratum material, and the properties of grouting material, the paper indicates that the method of using the grouting materials which have a property of low early strength and large fluidity is good for control the segments upward moving(however, the segments uplift during the construction and the later settlement should be considered) [2].
Zhengnan Shen analyze the reason of segments uplift through the factor of the physic-mechanical of stratum material, grouting and the shield posture, methods of controlling the segments uplift are provided [4].
After considering the two factors of size difference in tenon and deviation in joint handhole, can get the allowed maximum amount of slab staggering for structure allowed in Ningbo metro line 1 is 4 mm.
For N, the conclusion in this paper is that the number of the float stable ring from shield tail is 14, however, the value of N is affected by many factors(geological conditions and the construction parameters), if these factors change, float stable ring should be fitted again.

Introduction Ceramic tool materials have been widely used in dry cutting and high speed machining because of the excellent mechanical properties.
The hot-pressing technology parameters, including fabrication temperature, pressure and duration time, finally govern the mechanical properties of the ceramic tool materials under the condition of the same compositions.
Fabrication temperature and duration time significantly affect the mechanical properties and microstructure of Si3N4 matrix ceramic tool materials [1].
However, it is very difficult to optimize the fabrication parameters for the desirable microstructure and mechanical properties by experiments.
However, those simulation models are not coupled with the fabrication temperature, which is essential to the mechanical properties of ceramic tool materials by the effect of those parameters on the microstructure evolution during fabrication.

According to the parameters of designed submerged floating tunnels at home and abroad, main factors that affect the dynamic response of submerged floating tunnel were analyzed by numerical method.
Effects of fctors on seismic response of submerged floating tunnel Mechanical property of submerged floating tunnel is affected by many factors.
The purpose of this paper is to reveal the relationship between factors and seismic response of submerged floating tunnel by analyzing the effects of several factors on the response of system, which may provide evidence to the optimization of the structural behavior.
In factor analysis, it is generally assumed that only one parameter of the structure change, the others remain unchanged.
Among factors that affect the internal force and deformation of submerged floating tunnel, tether spacing is very active.

Introduction Boron carbide B4C is technical ceramic with superior mechanical and chemical properties.
The development of microstructure, mechanical and tribological properties change was revealed according to phase's transformation.
Instrumented indentation (Zwick Z 2.5/TS1S tester, EN ISO-14577-1) was used to quantify the mechanical properties of the composites.
The phase transformation influenced the mechanical properties change in B4C/Al composites.
Table 1 Mechanical properties of B4C/Al composites.

The Effects of Laser Texturing Parameters on Wear Properties of Rollers with Fractal Geometry Hongbin Liu1,a , Daping Wan 1,b and Dejin Hu1,c 1School of Mechanical and Power Engineering, Shanghai Jiaotong University, Shanghai, China, 200030 ahunking2008@yahoo.com.cn; bwdp@sjtu.edu.cn; cdjhu@sjtu.edu.cn Keywords: Laser texturing, Fractal geometry, Friction and wear, Surface roughness Abstract.
The roller is major component for the production of high-quality steel and the service life of the roller is largely determined by the wear properties.
Thus, the processing parameters are linked with the wear properties of laser textured surface, which will provide better guidance for the processing.
The processing parameters of laser texturing are linked with the wear properties of roller surface based on the relationship between the fractal parameters and surface roughness.
Yang: Chinese Journal of Mechanical Engineering, Vol.39 (2003) No.7, pp.107-110.

Focusing on the practice pavement sections using LSAM as base in Hangzhou municipal roads, the effect factors of subgrade modulus, base modulus and base thickness on surface deflection and bending strain in base bottom is analyzed.
Based on the test of the large-stone asphalt macadam base on a road in Hangzhou, it is analyzed that how the subgrade modulus, base modulus, base thickness and thickness of the surface layer affect the mechanical properties of asphalt pavement structure by the software of BISAR3.0.
Table 5-Pavement structure and parameters Layer Location Material Thickness(cm) Modulus(MPa) Passion ratio Surface Upper surface AC-13 4 — 0.25 Middle surface AC-20 5 — 0.25 Bottom surface AC-25 7 — 0.25 Base LSAM 20~40:5 — 0.3 Sub-base Graded broken stone/ Slag 30 30~480:50 0.3 Subgrade — — 10~30:5 0.35 Main Factors Affecting Mechanical Behavior of LSAM Asphalt Pavement 2.1 Analysis of subgrade modulus In the analysis, the structure of pavement consists of 4+5+7cm surface layers, 30cm LSAM asphalt base and 30cm sub-base; while the other parameters remain unchanged, sub-base modulus ranges from 30Mpa to 480Mpa; under each selected sub-base modulus, the subgrade modulus increases from 10MPa to 30MPa.
It figures out how the base thickness affects the structural mechanics indexes of flexible base pavement, and the results are shown in Figure 5 and Figure 6.
Analysis of Influence of Base Structural Parameters on Mechanical Response of Asphalt Concrete Pavement[J].