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It was suggested that mechanical rubbing forces the polymer chains in the surface region to orient parallel to the rubbing direction [3], and this orientation of the polymer chains, having been confirmed using a variety of methods [4-8], is believed to be the key factor for the alignment of LC molecules.
Here, we demonstrate that mechanical rubbing creates optical anisotropy at PI surface.
Linearly polarized light reflected at an oblique angle of incidence from an absorbing sample becomes elliptically polarized, and this change in polarization contains useful information on the optical properties of the sample.
Spectroscopic ellipsometry (SE) is well suited for probing bulk optical properties, and has also been used to study rubbed PI films [7].
Whereas the opportunity for ellipsometry to be a real time monitor to obtain information in situ on dynamic properties is limited as optical anisotropy measurement by ellipsometry requires sample rotating.

That is, de-bonding of CFRP plate can be considered as an important factor of specimen failure.
Especially, CFRP plate whose mechanical properties and chemical resistance are excellent is recently used much.
The threshold level was fixed at 48dB considering the electrical and mechanical noise, and then measured data were analyzed in PC.
Used material properties were provided from manufacturer, and tensile strength and elastic modulus of CFRP plate were 2.7~3.0GPa and 165MPa, respectively.
This was attributed to the fact that in case of small strengthening width AE count was affected by partial composite action such as slip between concrete and CFRP plate.

Maier1,h 1 Lehrstuhl für Werkstoffkunde (Materials Science), University of Paderborn, Pohlweg 47-49, 33098 Paderborn, Germany 2German Aerospace Center (DLR), Institute of Materials Research, 51170 Köln, Germany 3 Department of Mechanical Engineering, Texas A&M University, College Station, TX 77843, USA 4 Siberian Physical-Technical Institute, Tomsk 634050, Russia 5 Department of Mechanical Engineering, University of Kentucky, Lexington, KY 40506-0503, USA aniendorf@mail.upb.de, bjayaram.dadda@dlr.de, cjan.lackmann@benteler.de, djamonroe848@tamu.edu, eikaraman@tamu.edu, fpanchenko@mail.tsu.ru, gkaraca@engr.uky.edu, hhmaier@mail.upb.de Keywords: shape memory alloys (SMA); martensitic phase transformation; nucleation, phase transformation; internal friction; martensite variants Abstract.
Introduction In recent years, high-temperature shape memory alloys (HTSMAs) have gained increasing attention owing to their attractive properties, which are of interest for applications in aerospace, automobile, robotic and energy exploration and conversion industries, where the operating temperatures are often well above 100 °C [1].
Many of the properties of CoNiGa HTSMAs such as structural and phase transformation characteristics [11,12] and fundamental shape memory and pseudoelastic behavior (i.e. transformation strains, stress and thermal hysteresis and cyclic stabilities as functions of temperature and stress) [13-17] have been thoroughly examined.
The stress state also affects the thermal hysteresis and the magnitude of the transformation strains of the [001]-oriented Co49Ni21Ga30 crystals.
Since the Schmidt factor of the prevailing {110} <001> slip system is zero in B2-ordered alloys such as NiTi and CoNiGa [18], the influence of dislocation slip is minimized in this orientation.

The effective scope in the production of mechanical engineering products is still limited by both the materials used and the design of the products.
In this case, the error of the arms, taking into account their parallel action, affects the positioning error of the end effector in a complex way.
Kovalkova, Аutomatisation of Calculation Method of Technological Parameters of Wiredrawing with Account of Speed Factor and Material Properties, Solid State Phenomena. 299 (2020) 552-558
Oglodkov, Investigation into the Formation of Texture, Microstructure, and Anisotropy of Properties during Rolling Sheets of the Aluminum–Lithium 1420 Alloy, Russian Journal of Non-Ferrous Metals. 59 (2018) 56-61
Bonnard, Design and dimensional synthesis of a Linear Delta robot with single legs for additive manufacturing, Journal of the Brazilian Society of Mechanical Sciences and Engineering. 41 (2019) 536

The Stress and Strain Analysis in the Broadening Stage of Multi-wedge Synchrostep Rolling Railway Axle by Cross-wedge Rolling Xuedao Shu1,a , Min Xiao 1, Chuanmin Li2 and Zhenghuan Hu2 1College of Mechanical Engineering and Mechanics, Ningbo University, China, 315211 2College of Mechanical Engineering, University of Science and Technology Beijing, China, 100083 ashuxuedao@nbu.edu.cn Keywords: Multi-wedge, Synchrostep, Cross-wedge Rolling, Railway axle, Stress and strain Abstract.
According to the references [6], to the any wedge: (2) (3) (4) (5) (6) From Eq.(2) to Eq.(6)： Here a is the forming angle, b is the spreading angle, m is the number of the rollers, r and d is the radius and diameter of the rolled-piece separately, R and D is the radius and diameter of the roller separately, dk is the roller diameter, k is the instant spread factor of the rolled-piece.
The following are the mechanical properties of materials in calculate: The elastic modulus of roll is E=210GPa, the Poisson ratio is v=0.3, the density is ρ＝7.82×103Kg/m3.
The strain distribution which showed in Fig. 4 indicates that non-rolled metal between the wedges hardly with any strain, so the strain in the thin areas rolled by three wedges was not affected during the broadening process.

Therefore, any attempt to control the product properties must be done through the understanding of the raw material properties and by the control of the processing parameters [3].
These failures affect the quality of the ceramic part, generating economic damages to the ceramic industries [5].
From this curve, it is possible to select the ceramic material part, that is able to be subjected to the temperature variations of the firing step and present the desired properties in the finished part.
It is dependent on the surface geometry, the nature of the flow (forced or natural) and the properties of the fluid (density, viscosity, thermal conductivity and specific heat).
Other factors should be taken into account when choosing the type of thermal insulation, such as the useful life and the average cost of maintenance.

Compare to traditional power supply of spot welding ,inverting spot welding has a lot of advantages :with small volume of transformer ,light ,integration of welding clamp ,transformer and secondary rectifier , it is used into the spot welding robot ,the drive power and assembly weight of the spot welding robot[3] ;the inverting frequency of inverting spot welding power supply could be tens thousands of Hz ,even hundreds of Hz ,so the speed of response and ability to control and discompose of the whole feedback control system is better than traditional frequency spot welding power supply ,and easy to realize automation and intelligent control ;according to frequency spot welding power supply ,inverting spot welding power supply can save 25% - 30% energy with high power factor and good energy-efficient economy ;in welding area ,inverting spot welding has the advantage of large range of current of forming stable nugget ,long life of electrode ,small electromagnetic elects ,no alternating
“skin” affect ,and big ability of spot welding dissimilar metal .Summing up the appeal ,inverting spot welding power supply is the best spot welding power supply with every technical specifications[4，5].
Optimize Circuit Parameters WITH ACA The Process of electric resistance spot welding is very complicated :the influence of technological parameter on quality of welding is nonlinear process ,and each technological parameter which works to each other, interferes each other ,affect the quality and the property of weldment .So it’s impossible to build accurate model in theory ,and determine optimal program with mathematical programming method.
References [1] XiHua Zhao .Pressure Welding [M] .Being Jing :Mechanical Industry Press ,1995 [2] Zhengxing Zhu ,Xiangming Yan ,Min Wang .Resistance Welding Technology [M] .Bei Jing : Mechanical Industry Press ,2002 :51-55 [3] Zhicheng Deng ,Jun Lin ,Juntao Wang .The Development of Spot Welding Power [J] .Shanxi Science and Technology ,2007(1) :132-134 [4] Ping Fang .A Review of the Application of Invert Technology to the Resistance Spot Welding [J] .Journal of Nanchang Institute of Aeronautical Technology ,2001 ,(3) :16-19 [5] Minyu Zhao ,The Research of Medium Frequency Inverter Resistance Spot Welding Control System Based on DSP [D] .Shenyang University of Technology ,2008 :14-20 [6] Xigong Li ,Ludong Yang ,Liang Zhang .20kHz High Frequency Inverter Power Supply for Resistance Welding [J] .Transactions of the China Welding Institution ,2006(2) :105-107 [7] EIBann，Mahmoud ,Filevoimitar ,Intelligent constant current control for resistance spot welding[J] .IEEE Intemational Conference

High-intensity neutron powder diffraction offers opportunities in time- and parameterresolved diffraction, in investigation of small samples, or the precise intensity measurement to determine structure factors of disordered samples or weak peak intensities by differential diffraction.
This preferred orientation, or texture, can determine a material’s properties or divulge a material’s history.
Structure factors: Disordered materials.
The determination of the structure factor of liquids or amorphous materials needs a very good counting statistics over a large Q-range.
Therefore, a high intensity of detected neutrons is needed, but also good detection stability, a low instrumental background, which has to be subtracted and affects statistics, a low wavelength and a reproducible, stable sample position and environment control.

Mechanical compression of as-coated TiO2 particles was first attempted by Hagfeldt et al.
This affects overall conversion efficiency which shows a saturation at the same thickness.
This situation is further affected by a relatively large internal resistance against the flow of photocurrent, which brings about a voltage loss (IR loss) and reduces fill factor (FF) of the I-V curve.
Apart from the photoanode, substrate of counterelectrode need not necessarily has transparent property like FTO and ITO.
It can supply a large photocurrent by exposure to sunlight without a large loss in fill factor (IR loss).

Copper was chosen for the tubes due to its high thermal conductivity, mechanical durability, and corrosion resistance—key properties for efficient heat transfer and system longevity.
The detail of thermal properties for both PCM and Copper can be referred to Table 3.
Thermo-physical properties of Paraffin Wax RT-82 and Copper Property Paraffin Wax RT82 Copper Density solid, ρm [kg/m3] - 8978 Density liquid, ρ1 [kg/m3] 770 - Specific heat, Cp1, Cps[J/kg.
All fin structures were integrated into the same triplex-tube shell-and-tube model, maintaining consistent boundary conditions, material properties, and PCM volume across simulations to ensure comparability.
Particular attention should be given to thermal stratification, onset of natural convection, and phase interface stability, as these factors can strongly influence the overall charging/discharging efficiency under variable HTF conditions.