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Investigation the Ultrasonic Vibration on Tin Soldering Welding of Copper Wires and Plates Thanh-Hai Nguyen1,2,a*, Truong Dang Khoa1,b, Bui Duy Khanh1,2,c, Dao Duy Qui1,2,d, and Hoang Ba Cuong3,e 1Faculty of Mechanical Engineering, Ho Chi Minh City University of Technology (HCMUT), Ho Chi Minh City, Vietnam, 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City 700000, Vietnam; 2Viet Nam National University of Ho Chi Minh City (VNUHCM), Linh Trung Ward, Thu Duc District, Ho Chi Minh City 700000, Vietnam. 3The Research Laboratories of Saigon High Tech Park Lot I3, N2 Road, Saigon High Tech Park, Thu Duc City, Ho Chi Minh City 700000, Vietnam ahaint@hcmut.edu.vn, btdkhoa.sdh19@hcmut.edu.vn, bdkhanh@hcmut.edu.vn duyqui@hcmut.edu.vn, ccuong.hoangba@shtplabs.org *Corresponding author: haint@hcmut.edu.vn Keywords: ultrasonic welding, ultrasonic soldering, copper soldering, curved reflector.
Kago et al. developed ultrasonic soldering device using 28 kHz and 150 W for increasing the properties of Sn-Bi alloy.
Soldering time and temperature are the two major factors affected to the joint strength and reaching highest value at 45 s.
Figure 3: Ultrasonic soldering welding equipment – (1) Ultrasonic generator; (2) Heat controller; (3) Ultrasonic transducer & horn; (4) Mechanical frame; (5) Tin tank; Copper plates with 10x2 mm2 are dipped in the liquid soldering tank.

The Effect of Alloying Elements on the Stability of Centerline Segregation Mihály Réger1,a, Balázs Verő 2,b, Ibolya Kardos3,c, Péter Varga 1,d 1 Budapest Tech, Bánki Donát Fac. of Mechanical and Safety Engineering, Hungary 2 Bay Zoltán Institution for Materials and Technology, Hungary 3 ISD DUNAFERR Co., Hungary a reger.mihaly@bgk.bmf.hu, bvero@bzaka.hu, cikardos@rt.dunaferr.hu, dvarga.peter@bgk.bmf.hu Keywords: centerline segregation, activity of carbon, effect of manganese, diffusional homogenization Abstract.
The centerline segregation is a disadvantageous failure of slabs which can affect the quality properties of the final products.
It is claimed by the authors without detailed explanation that manganese decreases the activity of carbon and this affects the carbon diffusion, but other elements like phosphorus can also play an important role [1].
Welding has a double role: it gives a rigid mechanical connection between the parts and protects the inner surfaces of the steel plates from oxidation.
The calculation method described above can be applied for this case by using the carbon activity field data and the "effective" carbon diffusion coefficient supposing that manganese does not affect considerably the value of the "effective" carbon diffusion coefficient.

The influence of temperature above 100℃ on concrete is apparent: besides the degradation of material strength which is usual for high temperature, decomposition of materials within concrete, phase change and moisture movement within concrete will seriously affect the mechanical behaviour of concrete everywhere.
Mechanical behaviour is the major factor determining the bearing capacity of a concrete structure under room temperature.
This model is essentially a chemical-hydro-thermo-mechanical model.
Constitutive equations for the mechanical response of the solid phase.
F., Concrete at High Temperature: Material Properties and Mathematical Models[M].

Die premature failure seriously affected the normal production.
The changes of process variables like stress and temperature will affect metal forming behavior.
So, all factors possibly causing workpiece changes of heat and force during every forging step should be considered carefully in simulations.
From the simulation results, the equivalent effective stresses have achieved 1290MPa in most of region such as transition surfaces between the side surfaces or tip surface and even reached 1940MPa in local area. 5CrNiMo hot-work die steel has stable mechanical properties below 500 and yield strength is about 1220MPa, tensile strength of about 1290MPa [7].
All above factors finally result in the most of blow energy had been received by dies and cause the sharp increase of die stress. ②The small round radius of transition between inner tip surface and inner side surfaces of grinding tooth increases outflow resistance of metal.

Table 1 Physical and mechanical properties of soil Layer No.
Analysis of Factors that Affect the Deformation [12] Influence of Retaining Pile Rigidity.
(3) By changing the factors that affect the deformation and analyzing, we can conclude that the displacement of pile can be controlled by enlarging the pile diameter, but there is little economic effect when the pile diameter reaches a certain value.

For intelligent photovoltaic systems, the overall block diagram of the system can be divided into optical systems, mechanical and actuators, photovoltaic sensing, signal acquisition and processing, drive and control, micro computers and their interfaces.
Other factors affecting the system must also be figured out, such as cost, weight, volume, and reliability and operating complexity.
It completely eliminates the subjective factors, reflecting the optical properties of the human eye more accurately and quickly, which has become the optometry technology development direction. 108 101 102 104 105 103 111 110 113 109 112 CCD CPU SRAM Circuit conversion Sync separation Address generator Signal amplifying circuit Sample hold Processor circuit Two values Processor Buffer Buffer Figure 1.

Surface roughness is used as the critical quality indicator for the machined surfaces and has influence on several properties such as wear resistance, fatigue strength, coefficient of friction, lubrication, wear rate and corrosion resistance of the machined parts (Feng and Wang, 2002).
The work of Davim and Figueira (2007), concerning the machinability evaluation of cold-work tool steel (D2) using statistical techniques, presented that the most influential factors for surface roughness are feed rate and cutting time, with percentage of contributions of 29.6% and 32.0%, respectively.
They also established surface roughness equations and demonstrated that surface finish is more directly affected by: in first term feed rate, secondly, tool’s nose radius, finally, by the cutting speed.
Singh and Rao (2007) predicted that the feed was the dominant factor determining the surface finish followed by nose radius and cutting velocity.
Prof. in Mechanical Engg.

Differences in the mechanical properties appear between weld metals, heat affected zone, and base metal.
Crack growth resistance curves, e.g., determined in terms of crack tip opening displacement (CTOD), exhibit variations in the crack growth resistance of the welded joint as a consequence of the local variations in the material properties.
Theoretical investigations have shown that also the local near-tip crack driving force (CDF) may deviate strongly from the far-field CDF, if the material properties vary locally.
The chemical compositions and mechanical properties of the BM and the OM and UM weld metals are given in Tabs. 1 and 2.
The strength mis-match factors M, i.e., the ratio between the yield stress of the weld metal to the yield stress of the BM, are 0.86 for the under- and 1.19 for the over-matched welded joint.

The key technical problems are mechanical analysis of its structure and optimization of the design of truss structure.
Finally both practical and economical factor was chosen to meet the engineering truss structure.
During the time of project construction, according to the terrain, quantities, concrete properties and enterprise ability and so on to adopt different mode of transportation.
Finite Element Model Finite element model will affect the reliability of the results.

Mineral powders, which have a certain proportion of aluminosilicate component, exhibit better astringent properties.
Marl in natural form, volcanic tuff, dune sands can be considered the most promising additives for improving the properties of cement paste, but undoubtedly, the decisive factor for assessing the effectiveness of the systems under study will be the activity of binders of multicomponent bonds.
This will slow down the beginning of setting of astringent ligaments and improve their properties.
It is quite possible that this will have a positive effect on the properties.
Muraviov, Mechanical properties of fiber-reinforced concrete using composite binders.