Using a neural network for predicting the average grain size in friction stir welding processes

2009 ◽  
Vol 87 (17-18) ◽  
pp. 1166-1174 ◽  
Author(s):  
Livan Fratini ◽  
Gianluca Buffa ◽  
Dina Palmeri
Keyword(s):  
Neural Network ◽  
Grain Size ◽  
Friction Stir Welding ◽  
Friction Stir ◽  
Average Grain Size ◽  
Welding Processes

Metallurgical Phenomena Modeling in Friction Stir Welding of Aluminium Alloys: Analytical Versus Neural Network Based Approaches

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
Livan Fratini ◽  
Gianluca Buffa
Keyword(s):  
Neural Network ◽  
Friction Stir Welding ◽  
Aluminium Alloys ◽  
Element Model ◽  
Simple Analytical Expression ◽  
Friction Stir ◽  
Average Grain Size ◽  
Trained Neural Network ◽  
Welding Processes ◽  
The Finite Element Model

In this paper, the metallurgical phenomena occurring in friction stir welding processes of AA6082-T6 and AA7075-T6 aluminum alloys are investigated. In particular, to predict the local values of the average grain size, either a simple analytical expression depending on a few material constants or a properly trained neural network is linked to the finite element model of the process. The utilized tools, which take as inputs the local values of strain, strain rate, and temperature, were developed starting from experimental data and numerical results.

Investigation of Microstructure and Mechanical Properties of Friction Stir Lap Jointed Ni Base Superalloy

2012 ◽  
Vol 724 ◽  
pp. 481-485
Author(s):  
Kuk Hyun Song ◽  
Kazuhiro Nakata
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Friction Stir Welding ◽  
Base Material ◽  
Lap Joints ◽  
Stir Zone ◽  
Inconel 600 ◽  
Friction Stir ◽  
Microstructure And Mechanical Properties ◽  
Average Grain Size

This study evaluated the microstructure and mechanical properties of friction stir welded lap joints. Inconel 600 and SS 400 as experimental materials were selected, and friction stir welding was carried out at tool rotation speed of 200 rpm and welding speed of 100 mm/min. Applying the friction stir welding was notably effective to reduce the grain size of the stir zone, as a result, the average grain size of Inconel 600 was reduced from 20 μm in the base material to 8.5 μm in the stir zone. Joint interface between Inconel 600 and SS 400 showed a sound weld without voids and cracks. Also, the hook, along the Inconel 600 alloy from SS 400, was formed at advancing side, which directly affected an increase in peel strength. In this study, we systematically discussed the evolution on microstructure and mechanical properties of friction stir lap jointed Inconel 600 and SS 400.

Synergetic Effect of ECAP and Friction Stir Welding on Microstructure and Mechanical Properties of Aluminium Sheets

2010 ◽  
Vol 667-669 ◽  
pp. 505-510
Author(s):  
Ilya Nikulin ◽  
Alla Kipelova ◽  
Sergey Malopheyev ◽  
Rustam Kaibyshev
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Grain Size ◽  
Friction Stir Welding ◽  
Base Metal ◽  
Synergetic Effect ◽  
Aluminum Matrix ◽  
Friction Stir ◽  
Microstructure And Mechanical Properties ◽  
Average Grain Size

Friction stir welding (FSW) was used to join the submicrocrystalline (SMC) grained Al-Cu-Mg-Ag sheets produced by equal channel angular pressing (ECAP) followed by hot rolling (HR). The effect of SPD and FSW on the microstructure and mechanical properties in the zone of base metal, as well as in the stirred zone (SZ) were examined. In addition, effect of standard heat treatment on microstructure and mechanical properties in these zones was considered. A refined microstructure with an average grain size of ~ 0.6 m and a portion of high-angle grain boundaries (HAGBs) of ~0.67 was produced in sheets by ECAP followed by HR at 250°C. The microcrystalline grained structure with average grain size of ~2.3 mm was found in joint weld. The moderate mechanical properties were revealed in SMC sheets and joint welds. Heat treatment considerably increases strength of the base metal as well as the joint welds. The higher strength of the alloy after T6 temper is attributed to the dense precipitations of  dispersoids having plate-like shape which are uniformly distributed within aluminum matrix. It was observed that FSW can produce full strength weld both in the tempered and in the un-tempered conditions.

CAFE modeling, neural network modeling, and experimental investigation of friction stir welding

2012 ◽  
Vol 227 (6) ◽  
pp. 1164-1176 ◽  
Author(s):  
C Patel ◽  
Sumitesh Das ◽  
R Ganesh Narayanan
Keyword(s):  
Neural Network ◽  
Grain Size ◽  
Finite Element ◽  
Friction Stir Welding ◽  
Yield Strength ◽  
Strain Rate ◽  
Virtual Machine ◽  
Hybrid Model ◽  
Neural Network Modeling ◽  
Friction Stir

The main aim of the present work is to develop a cellular automata finite element –artificial neural network (CAFE-ANN) hybrid model to predict the evolution of grain size and yield strength during friction stir welding. The CAFE model was developed by linking CA cells with elements in ABAQUS, a finite element code. Then a neural network was developed and trained appropriately by using the data obtained from the validated CAFE model that predicts the grain size and yield strength. The ANN results are validated. Finally it has been demonstrated that ANN can be used as a ‘virtual machine’ to examine the effect of rotational speed, welding speed, axial force and shoulder diameter on the variation in grain size and yield strength. The temperature and strain-rate distribution predicted by the thermal and strain-rate models are consistent with the existing results. The CAFE model grain size predictions are also accurate as compared to experiments. The grain size and yield strength predictions from ANN coincide well with the experimental values and CAFE model predictions. It has been demonstrated that CAFE-ANN hybrid model can be used as a ‘virtual machine’ to predict and analyze the effect of above said parameters on the grain size and yield strength evolution. The predicted influence is found to agree with some of the available results. In few cases, a slight deviation in the trend is witnessed as compared to literature results.

Metallurgical and Mechanical Properties of Friction Stir Welded Ultra Fine Grained Steel

2007 ◽  
Vol 539-543 ◽  
pp. 3727-3732 ◽  
Author(s):  
Satoshi Hirano ◽  
Kazutaka Okamoto ◽  
S.H.C. Park ◽  
K. Aota ◽  
T. Tsukamoto
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Friction Stir Welding ◽  
Cubic Boron Nitride ◽  
Joint Effect ◽  
The Other ◽  
Friction Stir ◽  
Polycrystalline Cubic Boron Nitride ◽  
Fine Grained ◽  
Average Grain Size

Friction Stir Welding (FSW) has been applied to ultra fine grained (UFG) steel which is the plane carbon steel with the average grain size of 1mm. The plates of 5mm thickness was successfully welded using pcBN tool (polycrystalline cubic boron nitride) and the metallurgical and mechanical properties of the joint were evaluated. In the stir zone, Bainite has been formed which shows the highest harness in the joint. On the other hand, grain growth is observed in the heat affected zone. The joint effect of 88% has been obtained for UFG steel by FSW process.

The Effects of Heat Treatment and Cold Working on the Microstructure of Aluminum Alloys Welded by Friction Stir Welding (FSW) Technique

2011 ◽  
Vol 409 ◽  
pp. 287-292
Author(s):  
M. Mohammadtaheri ◽  
M. Haddad-Sabzevar ◽  
Mohammad Mazinani
Keyword(s):  
Grain Size ◽  
Friction Stir Welding ◽  
Aluminum Alloys ◽  
Cold Work ◽  
Base Material ◽  
Work Conditions ◽  
Weld Nugget ◽  
Hardness Profile ◽  
Friction Stir ◽  
Average Grain Size

The application of hot deformation during Friction Stir Welding (FSW) gives rise to produce a weld nugget consisting usually of dynamically recrystallized grains whose size is substantially lower than that of the base material. In the present study, several specimens with different conditions were first prepared using 2024 and 5083 aluminum alloys, which were then welded with FSW method. The microstructures of weld nugget in both series of specimens were examined using optical and scanning electron microscopes. The specimen of 2024 with anneal (O) and artificial aging (T6) conditions, and type 5083 with anneal (O), 30% and 50% cold work conditions were friction stir welded. Grain size distribution, hardness and temperature profiles in the welded zones were determined in order to obtain the relationship between the grain structure and the hardness profile in these regions. In each alloy, the average grain size in the weld nuggets was identical. The hardness of nugget zones in each alloy was the same due to their similar microstructures. According to the results obtained in this investigation, the initial microstructure showed no considerable effect on final microstructure and hardness of the weld nuggets, which this effect may be attributed to continuous dynamic recrystallization phenomenon.

Use of Novel Welding Technologies for High-Entropy Alloys Joining

2018 ◽  
Vol 941 ◽  
pp. 919-924 ◽  
Author(s):  
Sergey Zherebtsov ◽  
Nikita Stepanov ◽  
Dmitry Shaysultanov ◽  
Sergey Malopheyev ◽  
Igor Vysotskiy ◽  
...  
Keyword(s):  
Grain Size ◽  
Friction Stir Welding ◽  
Laser Beam ◽  
Weld Zone ◽  
Laser Beam Welding ◽  
High Entropy Alloys ◽  
Pronounced Increase ◽  
High Entropy ◽  
Friction Stir ◽  
Average Grain Size

Laser beam welding and friction stir welding of high entropy alloys (HEA) of the CoCrFeNiMn system were studied. The HEAs were produced by self-propagating high-temperature synthesis (SHS). Along with the principal elements, Al, C, S, and Si impurities were detected in the composition of the alloys. The as-cast alloys consisted of columnar fcc grains with coarse precipitates of MnS and fine Cr-rich M23C6carbides. Laser beam welding resulted in the formation of a defect-free weld joint. Precipitation of nanoscale B2 phase particles in the weld zone leaded to a pronounced increase in microhardness from ~150 HV of the base material to ~220 HV in the fusion zone. Friction stir welding (FSW) of a recrystallized state of the HEA with the average grain size of 3-5 μm resulted in the formation of a fine microstructure with a grain size of ~1.5 μm in the most strained area. Noticeable rise in strength and some decrease in ductility of the processed alloy in comparison with the initial condition can be associated with the formation of nanosized M23C6carbides.

A Friction Stir Welding Platform of Thin Plates

2012 ◽  
Vol 628 ◽  
pp. 206-210 ◽  
Author(s):  
Jia Liang Zhang ◽  
Bei Zhi Li ◽  
Xin Chao Zhang ◽  
Qing Xia Wang
Keyword(s):  
Friction Stir Welding ◽  
Virtual Instrument ◽  
Production Efficiency ◽  
Cost Effective ◽  
Field Analysis ◽  
Sensor Data ◽  
Thin Plates ◽  
Increase Production Efficiency ◽  
Friction Stir ◽  
Welding Processes

Friction stir welding processes involve many variables. Engineers and operators often find it difficult to effectively design or control it. The objective of this work is to develop a friction stir welding platform of thin plates to improve welding quality and to increase production efficiency. The study is conducted by using finite element modeling and temperature field analysis technology to obtain optimization parameters, and using virtual instrument, multi-sensor data fusion to monitor the force of the stirring spindle. Experiment results show that the developed platform can reach the requirements of processing quality and is cost-effective.

The Use of Bobbin Tools for Friction Stir Welding of Aluminium Alloys

2010 ◽  
Vol 638-642 ◽  
pp. 1179-1184 ◽  
Author(s):  
Philip L. Threadgill ◽  
M.M.Z. Ahmed ◽  
Jonathan P. Martin ◽  
Jonathan G. Perrett ◽  
Bradley P. Wynne
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Friction Stir Welding ◽  
Cross Section ◽  
Axial Force ◽  
Aluminium Alloys ◽  
Processing Parameters ◽  
Machine Design ◽  
Friction Stir ◽  
Triangular Zone

The use of a double sided friction stir welding tool (known as a bobbin tool) has the advantage of giving a processed zone in the workpiece which is more or less rectangular in cross section, as opposed the triangular zone which is more typically found when conventional friction stir welding tool designs are used. In addition, the net axial force on the workpiece is almost zero, which has significant beneficial implications in machine design and cost. However, the response of these tools in generating fine microstructures in the nugget area has not been established. The paper presents detailed metallographic analyses of microstructures produced in 25mm AA6082-T6 aluminium wrought alloy, and examines grain size, texture and mechanical properties as a function of processing parameters and tool design, and offers comparison with data from welds made with conventional tools.

scholarly journals Design and Fabrication of Friction Stir Welding End-Effector for an ABB IRB1410 Robot

2016 ◽  
Vol 5 (2) ◽  
pp. 98
Author(s):  
Santosh Vanama
Keyword(s):  
Friction Stir Welding ◽  
High Strength ◽  
Fusion Welding ◽  
Fusion Temperature ◽  
End Effector ◽  
Friction Stir ◽  
Aluminum Sheets ◽  
Operation Pressure ◽  
Welding Processes ◽  
Tool Rotation

<p>The paper propose modelling and fabrication of friction stir welding end-effector for ABB IRB1410 robot. A dynamically developing version of pressure welding processes, join material without reaching the fusion temperature called friction stir welding. As friction stir welding occurs in solid state, no solidification structures are created thereby eliminating the brittle and eutectic phase’s common to fusion welding of high strength aluminium alloys. In this paper, Friction stir welding is applied to aluminum sheets of 2 mm thickness. A prototype setup is developed to monitor the evolution of main forces and tool temperature during the operation. Pressure of a gripper plays a major role for tool rotation and developing torque.  Fabrication of the tool has done. Force calculations are done by placing the sensors on the outer surface of gripper. Methods of evaluating weld quality are surveyed as well.</p>

Sign in / Sign up

Export Citation Format

Share Document