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The paper regarding the HTM - Hydrogen Treatment of Materials as an attractive method for controlling microstructure and improving final mechanical properties of titanium alloys.
Hydrogen damage in titanium alloys The undesirable nature of the effects of hydrogen on the properties of titanium alloys is manifested primarily in the drop plastic properties, the impact resistance, and the formation and development of cracks in the structure.
Hydrogen may also affect the plastic flow of metals.
Increased or decreased yield strengths, serrated yielding, altered work-hardening rates, as well as lowered fatigue and creep properties have been reported [4,5].
This high-temperature treatment is very efficient for changing the microstructure and mechanical properties of two-phase titanium alloys.

Compression test on the porous scaffolds demonstrated that doping 10 mol% of strontium in HA has increased the compressive strength by a factor of two compared to the undoped HA with 1.81±0.26 MPa at 41% porosity.
Nonetheless, the mechanical properties of porous materials should be strongly affected not only by the intrinsic strength of the ceramic walls, but also by the pore structure [2].
Then, the porous scaffolds were characterized using FESEM and XRD while the mechanical test were conducted using Universal Tensile Machine.
A Lloyd LR10K mechanical tester with 10 kN load cells was used for the compression mechanical tests.
It was reported that bone ingrowth after 3 months of implantation could increase the mechanical strength from 2-20 MPa [4] resulting in improved in vivo mechanical performance.

Researchers have investigated using natural fiber to improve the mechanical properties of polymer composites [1,2].
It will deteriorate the mechanical properties and the use of natural fibers as reinforcements in the polymer matrix.
The partial removal of hemicellulose, lignin, wax, and impurities on the fiber surface due to alkali treatment greatly affected the composite properties.
Characterization and Factors Effecting Fiber Properties, 2000
Mechanical, Thermal and Water Absorption Properties of Kenaf-Fiber-Based Polypropylene and Poly(Butylene Succinate) Composites.

The addition of the extrusion process and/or the ECAP process in fabrication can be an option to improve its properties.
However, Mg weakness in terms of mechanical properties and degradation rates need to be improved.
Characterization of miniplate samples includes visual forms, a microstructure with an optical microscope (OM) and mechanical properties.
Mechanical properties test was carried out through a three-point bending test (ASTM E290) with test speed of 10mm/min.
Besides the density factor, the grain size of the miniplate affected the bending test results.

The mechanical and corrosion properties of stainless steels welds are highly dependent on microstructure.
The heat input of laser beam welding is mainly affected by three different factors: absorption, laser power, and welding speed.
The heat affected zones were narrow in each cases.
Mechanical properties, microstructural stability and kinetics of σ phase formation in 29Cr-6Ni-2Mo-0.38N super duplex stainless steel.
Khourshid, T Sharef: Effect of Laser Beam Welding Parameters on Microstructure and Properties of Duplex Stainless Steel, Materials Sciences and Applications, 2011, 2, 1443-1451

Research indicates that internal structure of materials will change and produce micro-voids, micro-cracks and other forms of micro-defects acted by factors of some load or external forces .
The so-called damage is that micro-structure and meso-structure of material change under temperature,load and environmental factors during smelting or processing,which causes micro-defects to nucleate,grow,propagate and coalesce and results in deterioration of macroscopic mechanical properties of material.
Ayada thought that the hydrostatic stress and equivalent strain are the main factors which affected the void growth.He proposed the ductile criterion as Eq. 7 [22]
Zeng: Chinese Journal of Mechanical Engineering, Vol. 38 (2002) Supp., pp.21-25.
Berg: International Journal of Mechanical Sciences, Vol. 32 (1966) , pp.614

The single tool grains affect the workpiece surface during grinding in the separated areas of deformation.
The residual stress is an important factor in influencing usable properties of machine parts.
Introduction The volume of applied heat, intensity of mechanical load of ground surface and also the structural changes influence the intensity of residual stress.
The residual stress behaviour depends on all parameters of surface integrity and their mutual connection including material properties.
The above reached results were formed up by means of the national grant GA CR 101/09/0504 - Research of influence of finishing and progressive methods of machining on function properties of design notches in term possible catastrophic effects.

This lead to a fact that the impact force was not affected by the change of the reinforcement ratio, but mainly affected by the change of the slab thickness.
This model's mechanical behavior is a continuum concrete damage model, based on plasticity.
Concrete materials properties.
The interaction between the impact load and the concrete slab is defined by the (explicit) surface-to-surface contact available in ABAQUS / Explicit [7], the mechanical constraint formulation kinematic contact technique was active in describing the selection of contact properties.
Obviously, the load-time history is not affected noticeably by increasing the reinforcement ratio.

Previous studies [3-6] had been greatly focused on machining of Ti6A14V and their research issues can be summarized as: 1) mechanisms of material removal and chip formation, 2) wear behavior of tool and chemical reactions in the contact zone between cutter and workpiece, 3) cutting forces, vibrations and temperatures during milling and their affecting factors, 4) integrities of milled surface and their influential factors, 5) high speed milling and new tool technologies.
The workpiece used is Ti6A14V titanium alloys, whose mechanical parameters are given in Table 1.
For analyzing the affecting weight of each cutting parameter, an empirical equation is used for regressing and the result is described by Eq. 1.
Ra=1.7322vc-0.0285ar0.2461vr0.198 (1) (a) with feed per revolution (b) with radial cutting depth (c) with cutting speed Fig. 2 Influences of cutting parameters on surface roughness ar D θmax θ fz vc Ti6Al4V Cutter θmax Equal area hm a b h a b Fig. 4 Illustration of the contact zone between cutter and workpiece and the average cutting thickness It can be seen from Eq.1 that the primary affecting factor on surface roughness is the radial cutting depth and the least one is the cutting speed.
Among cutting parameters, radial cutting depth is the most influential factor on surface roughness while cutting speed is the least.

Effect of sodium nitrate addition on the sintered glass (glass-ceramic) properties were studied.
Glass-ceramic typically have better mechanical properties compared to the parent amorphous glass [4].
Nevertheless, recent studies showed certain composition of glass-ceramics exhibited good bioactivity together with improved mechanical property.
In this study, comparison between sodium-contained glass-ceramic (Na-GC) and sodium-free glass-ceramic (GC) properties was made.
Surface morphology of (a) GC and (b) Na-GC together with their respective EDX analysis (a.i) and (b.i) after immersed in SBF solution for 14 days Conclusion This research study indicate that by varying the sodium nitrate content in SiO2-CaO-NaO-P2O5 glass composition made by sol-gel route does affected the sintered glass properties.