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Various materials consolidated are described in terms of their densities, microstructures and mechanical properties.
Introduction Nanomaterials are attractive as they promise to offer unique and considerably enhanced properties [1].
Also, the emphasis is on processing and its effects on ultrafine/nano structures; although the resulting mechanical properties including hardness, strength and ductility are presented, it has not been attempted to compare results from different studies since mechanical properties are sensitive to the level of defects which varies considerably between investigations.
Mechanical properties.
As this brief overview demonstrates, consolidation of fine particles by severe plastic deformation has exhibited great potential in producing bulk nanostructured materials with enhanced mechanical properties.

This compound has been obtained by a number of preparation routines, usually by chemical synthesis, mechanical action from precursor compounds or by calcinations of several types of bones [6].
The method is quite simple, feasible to large scale production, and the raw material is abundant, factors that make the transformation process attractive from the industrial point of view.
It can be observed that the most probable particle diameter is about 1.0µm, which is certainly further decreased by mechanical milling.
Nevertheless, studies have shown that the calcination temperature can affect crystallinity, increasing the lattice parameter [10, 17]. 10 20 30 40 50 60 70 (12h) (10h) (8h) (6h) (4h) 2θθθθ (Degrees) Intensity (Arbitrary Units) 20 30 40 50 60 0 200 400 600 800 1000 1200 ♦(321) ♦(112) ♦(202) ♦(501) ♦(313) ♦(322) ♦(203) ♦(113) ♦(131) ♦(212) ♦(301) ♦(210) ♦(102) ♦(111) ♦(200) ♦(312) ♦(222) ♦(213) ♦(402) ♦(410) ♦(310) ♦(004) ♦(002) ♦(300) ♦(211) 2θθθθ (Degrees) Intensity (Arbitrary Units) ♦ PURE HA a) b) Fig. 3. a) X-ray diffraction patterns for the materials calcined at 4, 6, 7, 10 and 12 hours and milled for 4 hours; b) Material calcined at 12 hours and milled for 4 hours.
"Optical properties of hydroxyapatite obtained by mechanical alloying", J. of Physics and Chemistry of Solids 63, 1745-1757, (2002).

After the plasma arc scans the surface of the sheet metal, there will be an obvious change of micro hardness in the heated area, which will affect the increasing of bending angle to some extent.
In addition to the processing parameters and the physical properties, the changes in micro structure and phase transformations play an important role in the forming.
Table 1 shows the experimental results of Q235 sheets with 19 degree pre-bending angle by mechanical bending method.
Strain-hardening effects and phase transformation effects are also main factors to influence the forming process.
Zhang: China Mechanical Engineering, Vol.14 (2003), No.1, pp.75-78

New perspectives have opened for the manufacturing of products in precision engineering and in medical instrumentation not only by the special mechanical, optical, biochemical etc. properties but also the electrical ones of carbon black dotted silicone rubber.
This modulus is defined as 22 EEE ''+'=∗ further we obtain the material loss factor with EE '''=δtan .
The electric properties of the carbon dotted polymers are determined by the type, amount and the size of particles [6].
However the percentage of carbon strongly influences the mechanical properties of the material.
This pulling force can be affected by the pressure.

The cracks can be initiated by two aspects: internal and external factors.
Internal factors caused by the shrinkage of concrete material whereas external factors caused by several mechanisms, including excessive load, exposure to aggressive environments, procedures of construction and design errors [1].
A factor of 0.83 was applied for converting cube compressive strength into the cylinder compressive strength.
However, at some other studies, continued hydration of the cement matrix does not significantly affect the healing of cracks.
The addition of rice husk ash (RHA) to replace cement combined with 10% CaCO3 affect and accelerate the healing process.

Ao4, d 1Department of Tourism and Cuisine, Harbin University of Commerce, Harbin 150028, China 2School of Mechanical Engineering, Harbin University of Science and Technology, Harbin 150080, China 3School of Mechanical and Electrical Engineering, Harbin Institute of Technology, Harbin 150001, China apeiyinzhang@163.com, byu_ccna@163.com, cadai_ccna@163.com, daoyingjie@163.com Keywords: Tourism demand, Dynamic process, neural network, Abstract.
The parameters and are learning factors, called cognitive and social parameter respectively, and they are used to bias the particle’s search.
Many scholars have studied that the parameters is the key factors to affect the convergence of the PSO.
In particular, the adaptive mutation weight factor (AMWF) is determined as follows
The adaptive mutation weight factor (AMWF) is defined in Eq. (8) with = 1.2 and = 0.2.

Geometry of the porous ceramics, especially the roughness of hole surface, microporous, hole factors etc. affect the osteogenesis ability of this kind of compound[4].
Further study will be carried out on controlling pore size and shape, mechanical property and temperature condition of mesoporous hydroxyapatite prepared by using the Polystyrene microspheres as template.

A major problem of laser machining processes is thermal damage, which significantly alters the machined surface and subsurface properties of workpiece.
Furthermore, the rapid cooling of laser-ablated surface usually causes residual stress and cracks, and these adversely affect the strength, fatigue life and dimensions of part manufactured.
The good thermal conductivity of water and high mechanical shock pressure induced in the confined volume of water are anticipated to play the significant roles in cooling of workpiece and expelling of cut debris during the ablation.
Bhattacharyya, Pulsed Nd:YAG Laser Micro-turning of Alumina to Study the Effect of Overlap Factors on Surface Roughness Performance, IOP Conference Series: Materials Science and Engineering. 377 (2018) 1-7
Dumkum, Laser micro-milling under a thin and flowing water layer: A new concept of liquid-assisted laser machining process, Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture. 230 (2015) 376-380.

These alloys are used in the nuclear industry as fuel cladding due to their resistance to corrosion [3] at operating temperatures, good mechanical strength and relatively low thermal neutron capture cross-section (0.184 barns) [4].
These contaminants may also adversely affect the desirable chemical, mechanical and thermal properties of the metal as well.
These factors present a challenge when the sample is a non-conducting powder, such as zirconia (ZrO2).
These samples were run on the GD-OES to determine what the boundaries were for maintaining conductivity and mechanical strength.

In this paper, combined with geological conditions and rock mechanical properties of coal bed washout in east auxiliary roadway of Pingshuo Mine No.3, proposed support program of STCC supports through STCC short column experiments and theoretical analysis, by numerical analysis and on-site observations analyzed the stability of the roadway supported by STCC supports, provided a theoretical basis and technical support for the roadway in coal bed washout.
Fig.4 Parameters of STCC supports + bolt-mesh supporting Numerical Simulation on the Stability of East Auxiliary Roadway Surrounding Rock Mechanical Model of Roadway Surrounding Rock.
Top mechanical boundary conditions on the model was vertical load P =5.74MPa, limited horizontal movement on the model side and vertical movement on the model bottom.
Shown in figure 7, the stress concentration zones were formed at floor and its angle, the maximum of stress concentration was 13.4MPa at middle of floor, and the stress concentration factor was 2.33.
Stress concentration zone was formed in the deep zone of roadway floor and it's angle, the maximum of stress concentration was 13.4MPa, and the stress concentration factor was 2.33.