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Kaviany studied factors affect critical heat flux of Capillary artery evaporators, mainly the capillary-viscous and hydrodynamics-instability, by way modulating wicks and liquid artery.
Theoretical Calculation Three wicks properties prominently affect the thermal behavior in heat pipe: capillary radius R, the wick resistance or the permeability of the wick, and the effective thermal conductivity Keff.
Permeability is depending on the interface properties of wick material and working fluid.
A high equivalent thermal conductivity, high permeability, and a low capillary radius are optimized properties in most heat pipe’s wick design [7].
Journal of the Chinese Society of Mechanical Engineers. 27(1) (2006)1-5

Therefore it shows significant value in mechanical manufacturing field [2-4].
It is a new way of surface modification to titanium alloys, different from the popular hard coatings or films, which usually enhance wear resistance at the cost of degradation of fatigue properties.
It is known that the frictional force is affected by two factors: one is the adhesion force from the atomic interaction between two sliding surface in contact and another one is the force needed to deform the interacting asperities [9].
The combination of these two phases endowed the layer with appropriate comprehensive properties, moderate hardness, well balanced toughness and ductility.
Miyazaki, Mechanical properties of Ti–Ni shape memory thin films formed by sputtering, Materials Science and Engineering. 273-275(1999)754-757 [4] Clayton P, Tribological behavior of a titanium-nickel alloy, Wear. 162-164(1993)202-210

Cernescu2b 1,2 Politehnica'' University of Timisoara, Romania a dion@mec.upt.ro, b anghelcernescu@yahoo.com Keywords: crack length, fatigue crack rate, stress intensity factor range, overloads, crack growth retardation.
Applying fracture mechanics approach it was possible to correlate basic parameter for fatigue crack growth rate, da/dN, which represents the crack growth for one loading cycle, to the variation of stress intensity factor range, ΔK, in experiments with variable loading of constant amplitude, as presented in Fig. 2.
For the modelling and analysis of fatigue crack growth it's been used NASGRO code which calculates the fatigue crack growth rate based on a relation called "NASGRO equation" as: q C p th n K K K K K R f C dN da                                max1 1 1 1 (2) where: N - applied cycles number, a - crack lenght, R - stress ratio, ΔK - stress intensity factor range, C, n, p and q - material constant, f - function wich describes crack opening [2], ΔKth - threshold stress intensity factor range (Fig. 2), Kc - critical stress intensity factor.
According to NASGRO program data base mechanical properties of the alloy Al 2024-T3 are: - The yield strength: Rp0,2 = 365,4 MPa - The ultimate tensile strength: Rm = 455 MPa ΔKth dN da ΔK [MPa √m]   n KC dN da  K1C Region I Region II Region III [m/cycle] - Plain strain fracture toughness: KIc = 1042 MPa √mm Materials constant (C,n,p,q) for considered alloy, required in NASGRO equation, are selected based on curves da/dN = f(ΔK) (Fig. 4), given in references [6], [7], [8], [9] for different R.
Mirton, 2001 [2] ,,NASGRO - Fracture Mechanics and Fatigue Crack Growth Analysis Software'' - Reference Manual, Version 4.02, Sept. 2002 [3] Willenborg J., Engle R.M. and Wood H.A. - ,,A crack Growth Retardation Model Using an Effective Stress Concept'', AFFDL-TM-71-1-FBR, Wright Patterson Air Force Laboratory, ian. 1971 [4] Gallagher J.P., - ,,A Generalized Development of Yield Zone Models'', AFFDL-TM-74-28FBR, Wright Patterson Air Force Laboratory, ian. 1974 [5] Gallagher J.P., Hughes T.F. - ,,Influence of Yield Strength on Overload Affected Fatigue Crack Growth Behavior in 4340 Steel'', AFFDL-TM-74-27-FBR, Wright Patterson Air Force Laboratory, februarie 1974 [6] Frediani - ,, Experimental results forwarded to JSC by ESA'', University of PISA [7] Wanhill, R.

The paper details the process of electric stored-energy point welding, the structural and phase transitions in the welded seam and in the heat affected zone, as well as the influence of the welding process on the shape memory effect. 1.
Introduction Shape memory alloys have unique properties and the range of applications has been increasing in recent years.
Shape memory joining in general and of NiTi in particular is considered a difficult task, especially on what concerns welding in dissimilar architectures and is an additional factor to be considered when such materials are used [1-5].
Among the main difficulties related to shape memory alloys welding [6-10], one can mention: - overheating phenomena may lead to a permanent loss of the shape memory effect in some alloy families [11] and - the local change in the chemical composition may effectively destroy or affect the martensitic transformation due to the fact that the composition is an essential factor in the fabrication of shape memory alloys with a desired temperature range for shape recovery Friction [12], ultrasonic [13, 14] or electric resistance welding are solutions considered for welding shape memory alloys with the aim to reduce the heat affected areas.
The optimization of the welding parameters needs to be made in order to avoid local melting and the formation brittle of intermetallic compounds in the melted and heat affected zone.

Introduction Near-equiatomic TiNi shape memory alloys (SMAs) have been widely applied to aerospace, aviation and medicine industries owing to their superior functional properties such as shape memory effect, biocompatibility and excellent mechanical properties[1].
For instance, the effect of Nd addition and Al addition on the phase transformation and mechanical properties of TiNiFe shape memory alloys have been investigated [4,5].
The TiNiFe SMAs will be an ideal material for low temperature driving actuators because of its low phase transformation temperature and excellent mechanical properties.
It is known that the R phase transformation in the TiNi based SMAs supposed to be affected by four main factors which including Ni content in the alloy, ageing treatment, thermo-mechanical treatment and composition of the alloy [6].
Influence of Fe Addition on Phase Transformation Temperatures and Mechanical Properties of TiNi Shape Memory Alloys.

College of Materials and Metallurgy, Guizhou university, Guizyang 550003,China awaq0623@126.com, bqbliu2@263.net, cshuijie.qin@gmail.com Keywords: Laser technique; 40Cr steel; Laser surface alloying; Rare earth oxide Y2O3 Abstract: To increase the mechanical properties of the metal rollers, Mo and Mo+Y2O3 alloy powders were designed.
Since rare earth elements and its oxides are of excellent physical and chemical properties, such as unique electron shell structure, outstanding chemical activity and bigger ionic radius, they are usually used as the quality modifier for LSA treatment, which are able to achieve functions of deterioration, strengthening and purification as well as improvement of the performance of the metal alloy layer[4,5,6].
(a) (b ) Fig. 1 Morphology of the alloying layer:(a) without Y2O3 and (b) with Y2O3 As shown in Fig.2(a), from the surface to the substrate, the morphology of alloying layer without Y2O3 could be divided as alloying zone, transition zone and heat affected zone after LSA.
Consequently, the microstructure from the surface to the substrate of the alloy layer consists of alloying carbides, retained austenite and metastable ultrafine martensite in the heat affected zone[9]。.
The reason lies in two factors: On one hand, during LSA, rapid heating and solidifying leads to formation of fine grain size, which strengthens alloying layer.

It was found that casting with mold preheating temperatures would have influence on mechanical properties.
However, the gating design significantly affected the tensile properties and microstructure of the cast specimen [4].
CAD models of molds generated for finite element method mesh as well as casting parameters and material properties are put into Cast-Designer for the simulation.
Sabau, Srinath Viswanathan, Material properties for predicting wax pattern dimensions in investment casting, Materials Science and Engineering A362 (2003) 125–134
Tremblay, An investigation on microstructural and mechanical properties of solid mould investment casting of AZ91D magnesium alloy, Materials Characterization 59 (2008) 178-187

The effect of this factor has not been identified among the influences of other disturbance factors so far.
As an additional aspect, the tube dimensions affect the material characterization which leads to inaccurate material properties in numerical simulations.
In this contribution the scatter of some geometrical tubes properties and its impact on the 3-roll-push-bending process is investigated.
The characterization of the mechanical properties of tubes is done by tensile tests.
Thereby, the scatter of the mechanical material properties can be determined.

Possibility of Evaluating a Depth of Defects as a Hole in a Composite Dielectric Sample by the Parameters of Electric Response to Pulse Mechanical Excitation Petr Khorsova*, Anatoly Surzhikovb, Vladimir Surzhikovc and Roman Laasd National Research Tomsk Polytechnic University, 30, Lenina Ave., 634050, Tomsk, Russia *apnh1@tpu.ru, bsurzhikov@tpu.ru, civa1954@mail.ru, dromanlaas@tpu.ru Keywords: mechanoelectrical transfomations, mathematical model, defect, acoustic wave Abstract.
Introduction Designs from composite dielectric materials are used in aviation, space technology, automotive, mining, civil engineering and other areas in conditions of mechanical, thermal and other loads.
Besides, various technological factors in the manufacturing process can lead to product mismatch with project values: composition violation, a cavities formation, hit of various inclusions.
The essence of the phenomenon is that as a result of pulsed mechanical impact on the heterogeneous non-metallic materials occurs a variable electromagnetic field due to acoustic wave impact on dipole moments of double electric layers on the borders of dissimilar materials, as well as on inclusions with piezoelectric properties.
In the aftermath, the response begins to be affected by responses due to reflected acoustic waves from the sample boundaries and hole lateral boundaries.

To understand inhomogeneous deformation mechanism in polycrystalline metals is important matter for structural use materials, because the deformation behavior of each grain governs the mechanical properties such as deformability, ductility, fracture, and so on.
The mechanical test rig with 200N loading capacity is installed on the rotation stage.
We should take shape factor, Sf more than 0.3 at least.
These are affected by grain microstructure.
The partial deformations affected by local grain orientation are clearly observed in εx and εy.