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However, it’s difficult to control the processing parameters, because many factors involves.
The results show that the quality of the molten pool is affected by laser power and scanning speed.
Such results of experiments reveal the laser power, scanning speed, scanning space,layer thickness and other processing parameters influence the micro morphology and macro properties such as product quality and density, etc.
Conclusions The quality of the molten pool is affected by laser power and scanning speed.
[11] Weihui Wu and Yongqiang Yang : Journal of Mechanical Engineering In Chinese Vol.43 (2007),p.175-180.

Numerical simulation of chilled cast iron camshaft in sand casting process Binfeng Hea, Zhuqing Zhaob Department of Mechanical & Electronic Engineering, Xi’an University of Arts and Science, Xi’an, 710065 China agreatman_he@yahoo.com.cn, bzhaozhuqing1225@126.com Keywords: chilled cast iron; filling and solidification; numerical simulation Abstract.
There are many kinds of casting defects such as insufficient pouring, cooling separation, crack, and shrinkage and soon on were formed in the mold filling and the solidification process, which affect the final casting performance.
The development of automobile industry and engine power brings up more advanced requirement for the properties of camshaft.
There are many factors to affect the casting quality, but the most important affection is come from casting technology.

This means that electric conductance might be affected by distribution of the residual stress.
Electric conductivity was influenced by various factors such as solute atom content, dislocation, grain boundary, precursor phase, residual stress et al.
Therefore, it was certain that the property of electric wire such as electric conductivity were affected by a various deformation conditions.
Electric resistance measurement Electric resistance, R, was acquired by repeating measurement on the based of 4-probe method at longitudinal section of wire which was carefully removed from surface to core by mechanical polishing at 25℃, as shown in fig. 1, b).
Kim: Metal and Materials Vol. 2 (1996), p. 169 Wires Measured property Core Middle Surface Residual stress, σ [MPa]. -13.6±1.6 0 -23.6±0.3 4.5Φ wire Electric resistance, R[Ω], at 25℃ 0.270[Ω] - 0.273[Ω] Residual stress, σ [MPa]. 0 0 -16±2.1 2.3Φ wire Electric resistance, R[Ω], at 25℃ 1.098[Ω] - 1.105

The transient friction stress was estimated by using equations given in the literature and some mathematical factors concerning the estimated dislocation densities and the net rates of dislocation immobilization at the high and low strain rates.
It is now well established that a change in strain rate results in a temporary imbalance in the internal state variables and hence, transients are observed in the flow stress, which cannot be defined by a mechanical equation of state [3,4].
Assuming that β does not change significantly during deformation so that the factor [β/(MD0b2)].exp(Qdef/RT) can be considered to be a constant, equal to K (Eq. 6).
Solute drag as a factor affecting Qrex was discussed in more detail in another paper [16].
Cser: Mathematical and Physical Simulation of the Properties of Hot rolled Products (Elsevier Science, Amsterdam 1999), p. 156 [11] L.P.

When higher strain rate of 10 sec -1 was used, the area fraction of dynamically recrystallized grains increased substantially, but the average grain size was not affected.
Introduction As a nickel-based superalloy, alloy 718 is extensively used in the fabrication of critical components for turbine engines due to its excellent mechanical properties at elevated temperatures and good corrosion resistance.
Since mechanical properties of alloy 718 significantly depends on the grain size, prediction of grain size and its distribution of the hot deformed and/or reheated alloy 718 is very important [2,3].
Dynamic and static recrystallization was identified as major controlling factors for microstructure when the hot compression test and reheating were conducted. 2.

Two competing factors affect the wear rates of the composites.
Therefore, the composites incorporating graphite do not work for wear reduction, as the debit in mechanical properties is larger than the very small benefit in friction reduction.

Experiment Material and Environment The material used in this work was tubular steel API-P110 (Pangang Group Chendu Steel&Vanadium Co., Lid., China), whose chemical composition and mechanical properties is showed in Table 1.
Electrochemical factors were analyzed by the method based on mixed potential theory [8].
It was shown that pH was a key factor to decide on electrochemical reaction of steel in above solution.
And pH also affects anodic and cathodic reaction rate.
The cathodic current density in the solution at pH2.9 is bigger than about two factors as that at pH5.3 when potential is more negative than -0.9V.

Introduction A systematic study of hydrogen effects on the mechanical behavior of beta titanium alloys as well as the improvement of mechanical properties by using hydrogen as a temporary alloying element within a modified heat treatment called ThermoHydrogen Processing (THP) require an accurate determination of the hydrogen diffusion coefficient DH in the respective titanium alloy [1-3].
The results gained on the mechanical properties of hydrogenated beta titanium alloys are important for the prediction of the applicability range in hydrogen containing environments since hydrogen is known to be detrimental with respect to the mechanical properties of metals and alloys often leading to hydrogen embrittlement [6].
Fuselage parts of modern aircraft are typical applications for Ti 21S due to its high strength and good corrosion properties.
Corresponding activation energies Q and preexponential factors D0 were calculated and are listed in Tables 4 and 5 respectively.
Collings: Materials Properties Handbook: Titanium Alloys, (ASM International, Materialspark, Ohio, USA 1994)

Zircon was also used on a zircon-mullite system or as a filler in polymethyl methacrylate (PMMA)-based composites to improve their mechanical and thermal properties [4,5].
Investigation of crystal cells is essential since it can affect material properties, such as light absorbance, energy gap, and other optical properties [8].
Since structural parameters affect materials' behaviour, the study's results would favour our understanding of how material processing impacts applications.
Table 1 confirms that the 0.5 M calcined at 80 and 90 °C samples exhibit a relatively higher scale factor, indicating a higher crystallinity.
The reaction of powder sand after being milled with HCl in different molarities and temperatures affected the properties of crystal cells.

This results in semi-coupled thermo-mechanical models in a Lagrangian frame, where the thermal field is calculated prior to the mechanical field by separating the two analyses.
Table 1: Crack propagation law parameters DK*th (N/m3/2) K*max,th (N/m3/2) A (m1.5*(n+m)+1/Nn+m) n m 1834121 3352014 6.745E-23 1.65 0.56 Residual stresses affect crack propagation since they change the effective value of the total SIF at the crack tip, with both the minimum and the maximum SIF values generally affected in the same way, so as to leave unchanged the parameter ∆K.
Irving, The role of residual stress and heat affected zone properties on fatigue crack propagation in friction stir welded 2024-T351 aluminum joints, Int J Fatigue 25 (2003) 77–88
Palazzo, Influence of process parameters on microstructure and mechanical properties in AA2024-T3 friction stir welding.
Koak, Distortion control in welding by mechanical tensioning, Sci Technol Weld Joi 12 (2007), 620–633