Experimental Study on Friction Stir Welding of Dissimilar Al 6061 to Trip 780/800 Steel

2014 ◽  
Author(s):  
Xun Liu ◽  
Shuhuai Lan ◽  
Jun Ni

Friction stir welding (FSW) of dissimilar Al 6061 and TRIP 780/800 steel has been performed under different process parameters, including tool rotational speed, welding speed as well as the relative position of the tool axis to the abutting edge. Temperature and mechanical welding force was recorded during the process. Welding speed has an insignificant effect on either the maximum temperature or welding force. However, it can directly change the length of high temperature duration, which will accordingly influence temperature distribution in the weld and the microstructure. Higher rotational speed can effectively elevate weld temperature through greater amount of heat input. Metallurgical observations on weld cross sections perpendicular to the joint line was performed using both optical and scanning electron microscope. Microstructure evolution was analyzed and related to the force and temperature measurement results during the FSW process.

Author(s):  
Shubham Verma ◽  
Joy Prakash Misra ◽  
Meenu Gupta

The present study deals with the application of sequential procedure (i.e. steepest ascent) to obtain the optimum values of process parameters for conducting friction stir welding (FSW) experiments. A vertical milling machine is modified by fabricating fixture and tool ( H13 material) for performing FSW operation to join AA7039 plates. The steepest ascent technique is employed to design the experiments at different rotational speed, welding speed, and tilt angle. The ultimate tensile strength is considered as a performance characteristic for deciding the optimal levels. The mechanical and metallurgical characteristics of the joints are studied by executing tensile and microhardness tests. It is concluded from the graphical analysis of the steepest ascent technique that the optimal maximum and minimum values are 1812–1325 r/min for rotational speed, 43–26 mm/min for welding speed, and 2°–1.3° for tilt angle, respectively. Besides, optical microscope and scanning electron microscope are utilized for microstructural and fractographic analyses for a better understanding of the process.


2011 ◽  
Vol 295-297 ◽  
pp. 1929-1932
Author(s):  
Yi Min Tu ◽  
Ran Feng Qiu ◽  
Hong Xin Shi ◽  
Xin Zhang ◽  
Ke Ke Zhang

In order to obtain better understanding of the friction stir weldability of the magnesium alloy and provide some foundational information for improving mechanical properties of retardant magnesium alloy joints. A retardant magnesium alloy was weld using the method of friction stir welding. The influence of welding parameters on the strength of the joint was investigated. The maximum strength of 230 MPa was obtained from the joint welded at the tool rotational speed of 1000 r/min and welding speed of 750 mm/min.


Author(s):  
Fadi Al-Badour ◽  
Ibrahim H. Zainelabdeen ◽  
Rami K. Suleiman ◽  
Akeem Adesina

Abstract A hybrid additive manufacturing (AM) and friction stir processing (FSP) was used to heal a crack in 6 mm thick Al 6061-T6 aluminum alloy. AL-6061 is usually used in H2 high-pressure vessel fabrication as well as aerospace applications. In this work, Al-Si powder was utilized to fill the crack, then FSP was applied to consolidate and stir the powder with the base metal to fill and close the crack zone. Effect of FSP parameters including welding speed and tool rotation speed on the quality of repair was studied. Various mechanical tests, as well as characterization techniques such as hardness test, optical microscopy, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS), were employed to study the newly developed hybrid process on the quality of the repair. The investigation revealed that low rotational speed of 800 rpm results in minimum variation in microhardness. Moreover, the impact of welding speed on microhardness is smaller as compared to rotational speed.


Author(s):  
Shubham Verma ◽  
Joy Prakash Misra

This research investigates the effect of process parameters on real-time temperature and forces distribution during friction stir welding of AA7039. Experiments are conducted at different rotational speed, welding speed, and tilt angle conditions. For the experimentation, a low-cost real-time force-measuring fixture is indigenously developed in-house. However, eight K-type L-shaped thermocouples are used to examine the real-time temperature distribution. The forces in the z-direction are of a higher magnitude than the x-direction. The maximum force in the z-direction of 3.25 kN is witnessed for 2° tilt angle and a minimum of 2.1 kN for 26 mm/min of welding speed. The maximum force in the x-direction of 0.97 kN is obtained at 2° tilt angle and a minimum of 0.27 kN is obtained at 1.3° tilt angle. The maximum temperature of 390 °C is observed at 1812 r/min, whereas a minimum of 283 °C is observed at 43 mm/min of welding speed. The variations in temperature and force distribution during friction stir welding are also evaluated by utilizing two phenomenological models.


2017 ◽  
Vol 867 ◽  
pp. 97-104 ◽  
Author(s):  
T. Ganapathy ◽  
K. Lenin ◽  
K. Pannerselvam

This paper deals with the effective application of friction stir welding similar to butt joining technique.AL6063 T-6 alloys prepared in 125x 100 x 7mm thickness plate and FSW tool setup were H13 of diameter 25mm rotary tool with straight cylindrical pin profile. The maximum strength was considered for selection of combined process parameter. The process parameters were optimized using Taguchi method. The Rotational speed, welding speed, and axial speed are the main process parameter which taken into our consideration. The optimum process parameters are determined with reference to tensile strength of the joint. From the experiments, it was found the effects of welding parameter are the axial force is highest substantial parameter to determining the tensile strength of the joint. The paper which revealed the optimal values of process parameter are to acquire a maximum tensile strength of friction stir welded AL6063-T6 plates is 101.6Mpa with the combination level of rotational speed, welding speed and axial force are found to be 1100 RPM, 60 mm/min and 12.5 KN. validation test was carried out and results were nearer to the optimized results confirmed by the optimum results.


2015 ◽  
Vol 799-800 ◽  
pp. 251-255 ◽  
Author(s):  
Adeel Zafar ◽  
Mokhtar Awang ◽  
Sajjad Raza Khan ◽  
Sattar Emamian

Friction stir welding (FSW) of polymers is relatively a new concept among modern polymer joining techniques. This study demonstrates the applicability of FSW on 16mm thick nylon-6 plates at constant welding rate of 25mm/min and varying rotational speed between 300 to 1000RPM. A special designed tool was fabricated which has double shoulder and right-hand threaded pin profile. It has shown excellent results at relatively lower rotation speeds. Visual inspection and microstructural examination of cross sections showed that the cavities and tunnel defects appeared only at higher rotational speeds. A linear relationship was observed between temperature and rotation speed.


10.30544/221 ◽  
2017 ◽  
Vol 23 (2) ◽  
pp. 119-130 ◽  
Author(s):  
Nagabhushan Kumar Kadigithala ◽  
Vanitha C

Friction stir welding (FSW) is an efficient technique which can be used particularly for magnesium and aluminum alloys that are difficult to fusion weld. In this work AZ91D Mg alloy plates 3mm thick were friction stir welded at different process variables such as rotational speed and welding speed. The range of rotational speeds varied from 1025 to 1525 rpm, and the welding speed varied from 25 to 75 mm/min. Good quality welds were obtained under 1025 rpm of rotational speed with the welding speeds range from 25 to 75 mm/min. The microstructure of the AZ91D alloy consists of primary α-phase, eutectic α-phase and eutectic β (Mg17Al12) phase in the received condition (gravity die cast). The original dendrite grain structure completely disappeared and was transformed to fine equiaxed grains in stir zone (SZ). It was observed that there was a slight increase in hardness in SZ, because of fine recrystallized grain structure. The transverse tensile test results of weld specimens indicated constant strength irrespective of traveling speed. Fractrographic analysis of the friction stir welded specimens showed the brittle failure.


Metals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1236
Author(s):  
Ni ◽  
Mao ◽  
Qin ◽  
Xiao ◽  
Fu

Thermal cycles and deformations during high-speed micro friction stir welding (μFSW) under different welding conditions were studied by experimental methods. The results show that the peak temperature and elevated-temperature exposure time (t150) increased with the increasing of rotational speed and decreased with the increasing of welding speed. Increasing rotational speed or welding speed led to an increase in both heating and cooling rates. The joint fabricated by the pinless tool experienced a lower peak temperature, a shorter elevated-temperature exposure time, and a larger temperature gradient than that by the pin tool. The welded sheet presented an anti-saddle deformation character, with convex bending in a longitudinal direction and concave angular bending in a transverse direction. In comparison to the pin tool, the longitudinal maximum bending deformation, Zmax, of the joint fabricated by the pinless tool was reduced by 12.35%, and the transverse angular deformation, α, was reduced by 6.67%. In comparison to the steel backing plate, the Zmax of the joint produced using a copper backing plate was reduced by 40.66%, but the α was increased by 53.27%.


Author(s):  
C Ganesan ◽  
K Manonmani

Friction stir welding is a high potential technology for joining similar and dissimilar aluminum materials, utilized extensively in aerospace and automotive industrial applications to eradicate the problems like hot cracking, porosity, element loss, etc. due to the fusion welding process. This Research addresses the joining of two dissimilar materials of AA 5754 – H32 and AA 8090T6511 – Al-Li and their mechanical properties analysis with the effects of friction stir welding process parameters like tool rotational speed, welding speed and axial load on weld nugget zone formation quality. The significant roles of different tool pin profiles are also emphasized. A mathematical modeling equation was formed by using regression analysis to optimize the process parameter and found the best tool pin profile for defect-free weld nugget zone and higher tensile and hardness properties. This research also portrays the contribution of various pin profiles and each process parameter on the ultimate tensile strength by response surface methodology. The results indicate that the defect-free weld joints are observed with 1800 r/min of rotational speed, welding speed of 15 mm min−1 and 8.5 kN of axial load with hexagonal pin profile.


Sign in / Sign up

Export Citation Format

Share Document