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Parish and Fry [6] reported that the type of mower used can affect turfgrass quality.
Cutting and grass cutting has many variables that have an impact on crushing and some of the important variables are the cutting speed and the percentage of moisture from the vine, and there is a need to establish a model of cutting mechanics and to relate knife parameters to forage material properties [1, 7] In another study, [8] indicated that the highest energy consumption was with the straight knife configurations and the lowest energy consumption was with the greatest oblique angle configurations.
There are requirements for additional, cutting mechanics and for further studies of the cutting action of knives, and there is a need to create a model of cutting mechanics and to relate knife parameters to forage material properties [1, 13-15].
These results were similar to the findings of [12], who reported that variety, moisture content and cutting speed are the main factors affecting shearing strength and energy of the wheat stem.
Sulaiman, "Design and development of an integrated slasher (pulverizer) for sweet potato harvester: A Review " in 1st International Conference in Mechanical Engineering Research (ICMER 2011), 2011

Table1　Chemical composition Microstructures and Mechanical properties Fig.1 shows microstructure of DP steels.
This value was much higher than that of ferrite. fM was strongly related to mechanical properties.
Therefore, the factor related to coalescence seems to be effective for ductile fracture directly.
Fig.10 indicated the strain that void coalescence starts was mainly affected inter-void distance.
This indicates that void coalescence was mainly affected by inter-voids distances, not void fraction.

In fact, in the biomedical field, it continues to be one of the most used materials in prostheses thanks to its good corrosion resistance, high biocompatibility and its reliable mechanical properties as a replacement for hard tissues [4].
Properties changes by surface modification can be induced through different kinds of processing, such as: i) mechanical, e.g. burnishing, sandblasting and grinding processes; ii) physical, through plasma and laser treatments; iii) chemical, using acid and/or alkaline solutions.
The tribocorrosion behaviour of a material depends on the properties of the involved mating materials, on the mechanics of the tribological contact and is affected by the physico-chemical properties of the working environment.
Some limitations of this study concern the introduction of possible interference factors during the tests: i) related to interruptions of the tests in order to perform measurements, which could in part affect the results ii) the employment of simulated body fluid, which can only in part represent working conditions in body environment, iii) the analysis of one set of testing parameters.
Bayer, Mechanical Wear: Fundamentals and Testing, Second edi, Marcel Dekker, Inc., New York (USA), 2004.

Fabrication of functional components of desired physico-mechanical characteristics by layer-by-layer laser sintering is a widely studied problem in the world now.
Such a mathematical model has been developed taking into account the results of four-factor design experiment.
Comparing experimental data and obtained by the formula 1, we conclude that the radiation power, the speed of movement of the laser beam and the scanning step are the main parameters affecting the surface roughness of the surface of the sintered layer, but the temperature of heating the powder material must necessarily be included in the model of governance.
Therefore, the radiation power and speed of the laser beam are the main parameters affecting the thickness of the sintered layer, but the temperature of the heating step and the powder material must necessarily be included in the model of control.
A controlled modification of the properties of the sintered surface layer by dividing the processing modes into a semifinishing mode for the surface and a rough mode for the bulk is discussed, which makes it possible to increase the efficiency of the sintering process without the quality loss of the product surface.

Although FSW tool wear leads in addition to shorter tool life also to unexpected weld properties (structure, mechanical properties) only few studies have been addressed tool wear mechanism and tool materials selection [7, 9-11].
Savolainen et al. [7] investigated the factors affecting friction stir weldability of pure copper and its alloys as well as addressed correct welding parameters and performance of tool materials.
The use of sintered TiC-NiW and TiC-NiMo cermets was not recommended as they demonstrated poor mechanical properties (were too brittle).
In addition to adhesion diffusion is one of the factors of tool degradation at high temperatures.
Fujii, Investigation of the welding parameter dependent microstructure and mechanical properties of friction stir welded pure copper, Mater.

For the finger seal, leakage and wear are key factors to affect its sealing performance and service life.
Effective Elastic Properties for the Finger Seal Material To perform the finger seal analysis, the effective elastic properties of the finger seal material need first to be evaluated.
In Eq. 4, the compliance matrix of the weft yarn in local coordinate system, Swk, can be written in matrix form as (6) In Eq. 6, matrix elements are calculated by mechanical properties of the carbon fiber and carbon matrix according to the literature [6].
Effective Elastic Properties.
The effective elastic properties are assessed easily from the compliance matrix of the REV, which are used to represent the effective elastic properties of the 2.5D C/C composites.

The heat affected zone of weldments, in these thick section headers and thin walled boiler tubes, have been found to be susceptible to creep damage leading to cracking during service.
Introduction Austenitic stainless steels are used in electrical power generating plant for a range of components because they have good corrosion resistance and high temperature mechanical properties.
Various interactive factors contribute to both creep deformation and creep fracture and these have to be taken into account when evaluating service life.
However, one important factor is the initial microstructure of the fabricated component that enters service.
Creep deformation and fracture are controlled by a series of interacting factors, which need to be considered to evaluate service life [1].

The important role that the combination of TMP and the post-TMP treatment affects on the microstructure and thus on the properties of the alloys is emphasized.
The effects of Ta content and the different parameters of thermal mechanical processing (TMP) on microstructure and tensile properties were extensively analyzed [5, 6].
Microstructure and Mechanical Properties Tensile Properties The tensile properties of the three type microstructures of Ti-22Al-20Nb-7Ta alloy are shown in Fig 4.
Boundary strengthening of (O+B2) two phase mixture appears to be predominantly responsible for the increased strength, with other strengthening factors such as long range order, solid solution and texture effects.
Table 4 lists some experimental data, indicating that Ti-22Al-25Nb alloy with the duplex microstructure has good comprehensive mechanical properties.

Porosity and water content of concrete changing in wet-dry cycles were introduced, the failure mechanism of freeze-thaw and carbonation and the relation with pore structure, as well as its interaction influencing factors.
In recent years, some researchers have stimulated the damage of concrete by completing multi-factor.
Concrete affected by single destructive factor Wet-dry cycles.
In generally, carbonization rarely adversely affects mechanical properties of concrete and components [11].
Fitting carbonation depth of concrete which affected by Freeze-thaw test in natural environment.

Linear Analysis of Crack Propagation in a Solid Rocket Propellant Mubashir Gulzar NUST College of Electrical and Mechanical Engineering, National University of Sciences and Technology, H12, Islamabad, Pakistan amubashir_nustian@hotmail.com Keywords: Stress Intensity Factor (K), PSM 4 Sheet, LEFM, Poisson’s Ratio, Elastic Modulus Abstract.
But the decay and wear of a product cannot be totally avoided, so the life of the product is of primary concern particularly which can affect the human lives.
The material properties of PSM-4 are Elastic Modulus = 4.14 MPa Poisson’s Ratio = 0.5 Polyurethane material finds its major use in the modeling of solid rocket propellant.
Comparison of Results The Stress Intensity Factors at different applied loads can be compared for centrally cracked PSM-4 sheet specimen by using the above discussed experimental and software analysis results.
Gloss “A Photoelastic Investigation into the Effects of Cracks and Boundary Conditions on Stress Intensity Factors in Bonded Specimens” May, 2000 Blacksburg, Virginia [6] Dr.