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A few processing parameters involved with the LMDS include the laser power, traverse speed, powder feeding rate, and gas flow rate, etc, which affect many factors of LMDS technology.
The powder utilization ratio is influenced by many factors.
Discussion In addition, the powder utilization ratio is affected by other factors, such as fabricating continuity, powder feeding stability, material properties.
Furthermore, the other factors, such as material properties and spot diameter, would also lead to the change of powder utilization ratio.
In general, above-mentioned factors all contribute to the calculation results of powder utilization ratio, but the experimental results still effectivelly reflect the powder effciency during LMDS to some extent.

This has led to a wide range of applications as structural materials especiallyin aircraft structures[2,3,4].Thermal residual stress, produced by the curing and cooling process, is one of the important factors which can affect the mechanical performances of composites.Many researchers have fully investigated thermal resudual stress in composites through numerical or experimental methods [5,6,7].
Matrix-fiber debonding affects the performance of fiber-reinforced composites.It was found that the mechanical properties of composites under transverse compression were mainly controlled by interface strength and the failure of composites was due to the interface debonding[9,10,11,12,13].
It is clearly shown that S23 are higher than S13 and S33 in the two models,so S23 is the dominant factor resulting in debonding.
Conclusion Since thermal residual stress is one of the important factors which can affect the mechanical performances of composites, we presented a three-dimensional finite element model to investigate the effects of nanoparticles on the interface strength of unidirectional fiber reinforced composites.The comparison between the results of two models show that the thermal residual stress in the model with nanoparticles is significantly reduced, while the shear stress in the model without nanoparticles is the dominant factor resulting in interface debonding.
Mittal, Effect of architecture on mechanical properties of carbon/carbon composites, Composite Structures. 83 (2008)131-142

Since the properties of materials are strongly dependent on microstructure, the manufacturing parameters affect the material parameters during the process.
The importance of texture stems from the fact that all crystals are anisotropic in most the mechanical and thermal properties[13].
Consequently understanding the texture modifications leads to predicting the properties of the material either during machining (i.e. material parameter) or after machining (final properties).
Essentially, there are several factors affecting grain size evolutions.
In our case, in the area 1 (area right below the tool), the grain growth factors drive the grain evolution response while a little deeper in the material the grain refinement factors govern the evolution.

Optimum process conditions are obtained by analysis of variance (ANOVA) is used to understand the significance of process variables affecting dimension accuracy.
And, depending on the material, up to 100% density can be achieved with material properties comparable to those from conventional manufacturing methods.
Table 1 shows three different levels of the abovementioned four factors in our systematic investigation.
It is obviously that from Table 4 and Fig. 3 shows that the range order of the factors is SD> SB > SC > SA.
Material Properties, Fabrication parameters in selective laser sintering process, Rapid Prototyp.

The tensile specimen was made by machine according to HB965-82, and the mechanical properties of tensile specimen were tested by the MTS.
This also can get another conclusion that the uniform dispersion of CNTs is one of the key factors in the increasing the mechanical properties of composite.
This also can infer that the dispersion and the binding between the CNTs and the matrix are the key factors to strengthen the composite materials.
Because CNTs are very tiny and have good mechanical properties, the tensile sample is broken according to the tough fracture mechanism during the tensile test.
b) Further research on the material microstructure, especially the interface properties of the matrix and the reinforced phase, and find out the relation between microstructure of materials and mechanical properties.

The carbonation velocity coefficient, related to many factors, embodies the carbonation resistance of concrete.
Study the influencing factors of critical chloride concentration in composite beams.
Wu [8] studied the corrosion situation and mechanical properties of composite beams corroded by sulfate -chloride solution.
Xing: Experimental Studies on Mechanical Properties of Steel-Concrete Composite Beams Corroded by Sulfate, MS., Central South University, China, 2009,p.28
Li: Evaluation and Design of Load-Bearing Properties of Corroded Concrete Members (In Chinese), China Railway Publishing House, China, 2011, p.13

Thus, it was possible, after a plan of experiments was designed, to realize a series of samples to study process parameters influence on some mechanical and metallurgical properties of the pieces obtained with this process.
Three factors were considered: powder flow rate (q), laser power (P) and scanning speed (v).
SS measures the amount of additional variation in the response that is explained by the factor, given that all the other factors are already in the model, and MS is simply SS divided by the degrees of freedom of the factor.
The analysis of microstructure is fundamental to understand mechanical properties obtainable by the selective deposition laser process.
ANOVA analysis (Table 5) showed that all factors affect results for micro-hardness.

It was used widely in aerospace industries, because of its ideal properties.
It is also a quite complicated process to implement This technology directly affects the properties of products and working efficiency.
In practical application, however, most of path planning methods published only consider pure geometric factors and few methods involve mechanical factors for the sake of simplicity.
A few methods[6,7] did consider mechanical properties such as loading information and so on.
So, for the complicated surface geometry, topology, and varying mechanical properties within one mould surface, the fiber placement with multi reference paths might be worth probing.

The mechanical properties have been well characterized by turbine engine OEM’s and the alloy has been specified for use as static components and blades in gas turbine engines.
Several authors have studied the mechanical properties, fatigue behavior, thermal stability, and microstructure of ATI 718Plus alloy [5 - 8].
These modified aging heat treatments that improved dwell-fatigue crack growth resistance had minor impact on static tensile properties at 704ºC.
Furthermore, it is clear that additional microstructural factors such as g¢ size and distribution and grain size are important in determining fatigue crack growth rate.
From an engine design perspective, these equivalent, and in some cases superior crack growth properties, present a significant advantage for ATI 718Plus alloy with respect to damage tolerance capabilities for critical rotating components.

Mechanical stages are common but very important tools to all the fields in the modern world.
Moreover, based on the microscopic discoveries, the presence of friction would inevitably affect system dynamic response, especially for the presliding friction regime and the transition between these two regimes, since any subtle displacement or velocity variations was crucial to the high-precision motion requirement.
(5) It is mentioned in the original work that the function depends on many factors such as material properties, lubrication and temperature.
If a mechanical system subject to the friction force, then the equation of motion follows the Newton’s 2nd law.
Experimental Results The proposed scheme is performed on a common ball screw driven mechanical stage system operated in normal conditions.