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مقاله جوشكاري Finite element analysis of the thermo-mechanical behavior of the resistance spot welding

مقاله جوشكاري با عنوان : Finite element analysis of the thermo-mechanical behavior of the resistance spot welding

Murat Vural

چكيده:

In this study, the formation of the welding nugget and the effect of welding process parameters on nugget shape and size, have been studied. And a combined thermal-electrical-mechanical simulation system is done using a Finite Element Analysis program, and the effect of the welding parameters such as current, time, electrode force, contact resistance temperature distribution on the contact resistance were investigated. The results provided useful information source on the formation of the nugget, and thus provided opportunities to play first true estimate of the quality of welding process.

مقاله جوشكاري Parametric Studies and Finite Element Analysis of Welded Steel in Resistance Spot Welding Process

مقاله جوشكاري با عنوان : Parametric Studies and Finite Element Analysis of Welded Steel in Resistance Spot Welding Process

Kishore, N.1*, Sreenu, S.2, Ramachandran, N.3, Allesu, K.

چكيده :

Resistance Spot Welding (RSW) is a widely used joining process for fabricating sheet assemblies in the automotive,
marine and aerospace industries. Modern vehicles contain 2000-5000 spot welded points. The main requirements of
these automobile parts are corrosion resistance of chassis, the high strength values of sheets used, the stiffness of
welded joints when exposed to an external force and the ability to absorb impacts, along with low غير مجاز مي باشدt and comfort.
In RSW, electrodes travel on a predetermined path and make contact with the sheets at selected weld points to apply
force. Electric current is then turned on and flows through the sheets clamped between the electrodes. Due to the
contact resistance to current flow, the temperature rises from resistance heating. When the temperature reaches the
desired fusing temperature, a molten nugget is formed, the current is shut off after a designated time to allow the
nugget to cool down and solidification of the weld spot occurs under pressure. It is proposed to study the effect of
various parameters on nugget dimensions and strength of the weld joint in RSW and concentrating on different
material and thicknesses to get good weld joint at low غير مجاز مي باشدt and compared with analytical part done in Ansys.

مقاله جوشكاري A study on numerical analysis of the resistance spot welding process

مقاله جوشكاري با عنوان : A study on numerical analysis of the resistance spot welding process

H. Zhigang a, I.S. Kim b,*, J.S. Son b, H.H. Kim b, J.H. Seo b, K.C. Jang c,
D.K. Lee c, J.M. Kuk c

چكيده:

Purpose: Over the last few years, there has been a growing interest in quantitative representation of heat transfer
and fluid flow phenomena in weld pools in order to study relationships between the processing variables and
the quality of the weldment produced and to use this information for the optimization and mobilization of the
welding process.
Design/methodology/approach: A 2D axisymmetric Finite Element Method (FEM) model has been developed
to analyze the transient thermal behaviors of Resistance Spot Welding (RSW) process. In this model, the
temperature dependent material properties, phase change and convectional boundary conditions were taken
account for the improvement of the calculated accuracy, but the determination of the contact resistance at the
surface is moderately simplified in order to reduce the calculating time through the analysis.
Findings: The developed model has been employed the thermal history of the whole process (including cooling)
and temperature distributions for any position in the weldment

مو ز ه

تعريف موزه:

مقاله جوشكاري Modeling and Fuzzy Control of the Resistance Spot Welding Process

مقاله جوشكاري با عنوان : Modeling and Fuzzy Control of the Resistance Spot Welding Process

Xingqiao Chen, Keiiji Araki, Takeshi Miziiiio

چكيده :

This paper establishes a welding energy model and describes a hzzy adaptive process control
scheme for a resistance spot welding system.
For a welding system, it is not easy to measure with on-line the output, the nugget size, by usual
measuring method. And it is also difficult to control the welding process in real time . The paper
proposes a new method with input welding energy to estimate the nugget size and to reckon the
welding process. An optimal welding energy reference model is founded compared with different
input method of welding energy. A fizzy adaptive process control scheme with the model is also,
here, described to realize real time control and to improve control performance.
The results of simulation and experiments show that the reference model is effective on reducing
loss energy and prodiicing a sound nugget and the hzzy adaptive control scheme may obtain an
optimal control process for resistance spot welding

نقد موزه هنر سانفرانسيسكو

پس از زلزله سهمگين <لوما پرتيا> در سال 1989 كه در پي آن ساختمان موزه ديانگ بسيار آسيب ديد مسئولان موزه در صدد بازسازي بنا بر آمدند و طي مطالعات گسترده اي فهرستي از اسامي معماراني كه براي اين منظور شرايط لازم را داشتند تهيه شد.

هر چند كه در اين فهرست اسامي معماراني چون: مه ير - گهري - پيانو و بوتا ديده مي شد *جاكوب هرزوگ* و *پي ير دمورن* جهت طراحي موزه انتخاب شدنداين دو معمار سوئيسي كه به پاس آثار بديع خود در سال 2001 ميلادي مفتخر به كسب جوايز معتبر *پرايتزكر* در فاصله سالهاي 1970-75 معماري را نزد *آلدو روسي* آموختند و در سايل 1987 شركت هرتزوگ دمورن و همكاران را تاسيس كردند.

فايل مورد نظر پاورپوينت بوده و داراي 12 اسلايد ميباشد.

موزه هنرهاي معاصر تهران

در مورد موزه:

در طراحي موزه هنرهاي معاصر دو ديدگاه مورد بررسي قرار گرفته است يكي در محوطه ي اطراف سايت يعني پارك لاله كه پارك نسبتا بزرگي است و ديگري مسير دسترسي كه در كنار محور هاي ارتباطي پارك است.

كامران ديبا در طراحي از موزه حياط مركزي را انتخاب كرد كه علاوه بر اينكه يكي از نشانه هاي معماري ايراني باشد بتواند فضايي مجزا از پارك را ايجاد كند.علاوه بر آن كامران ديبا با طراحي ديد مناسب از حياط مركزي به پارك سعي بر برقراري رابطه با پارك نيز دارد.

اين رابطه در طراحي داخلي نيز با پنجره هاي ديواري وسقفي حفظ شده است.

فايل مورد نظر پاورپوينت بوده و داراي 15اسلايد ميباشد

مقاله جوشكاري Study of Forward Method on Imaging of Nugget in Resistance Spot Welding

مقاله جوشكاري با عنوان : Study of Forward Method on Imaging of Nugget in Resistance Spot Welding

Wenbo Xuan, Zhen Luo, Yang Li, Naifeng Fan

چكيده:

Inversion imaging of nugget in resistance spot
welding (RSW) is a new developing method of monitoring the
welding quality in RSW in recent years, which is based on the
rapid developments of the inverse problems in mathematics
and physics. This paper does some research on the forward
problem of inversion imaging of nugget and establishes the
forward model of RSW on the basis of the forward theory and
the electromagnetic field theory. And the soft wares of
MATLAB and ANSYS are used to simulate the
electromagnetic field of the forward model. The model’s
reliability is verified by comparing the experimental results
with the simulated results, which makes a good foundation for
the inversion imaging of nugget in RSW.

نقد راه آهن ليون فرانسه

معماري هاي - تك

مقاله جوشكاري Finite element analysis of resistance spot welding process

مقاله جوشكاري با عنوان : Finite element analysis of resistance spot welding process

Guo Zhong

چكيده :

A coupled finite element model is developed to
analyze the transient thermal and mechanical behaviors of
Resistance Spot Welding (RSW) process using commercial
software ANSYS. A direct-coupled electrical-thermal Finite
Element Analysis (FEA) is firstly performed to simulate the
transient thermal characteristics of RSW process. The thermal
history of the whole process and the temperature distribution of
the weldment are obtained through the analysis. Then based on
the thermal results a sequential coupled thermo-elastic-plastic
analysis is conducted to determine the mechanical features of
RSW process. The mechanical features, including the
distributions of the contact pressure at both the faying surface
and the electrode-workpiece interface, the stress and strain
distributions in the weldment and their changes during the RSW
process and the deformation of the weldment are also calculated.