Effects of Friction Stir Welding Parameters on Microstructures and Mechanical Properties of Brass Joints

The aim of this research was to investigate the effect of friction stir welding (FSW) parameters on microstructure and mechanical properties of Sc-modified AA2519 extrusion joints. The workpiece was welded by FSW in non-heat-treated condition with seven different sets of welding parameters. For each obtained joint macrostructure and microstructure observations were performed. Mechanical properties of joints were investigated using tensile test together with localization of fracture location. Joint efficiencies were established by comparing measured joints tensile strength to the value for base material. The obtained results show that investigated FSW joints of Sc-modified AA2519 in the non-heat-treated condition have joint efficiency within the range 87–95%. In the joints obtained with the lowest ratio of the tool rotation speed to the tool traverse speed, the occurrence of imperfections (voids) localized in the stir zone was reported. Three selected samples were subjected to further investigations consisting microhardness distribution and scanning electron microscopy fractography analysis. As the result of dynamic recrystallization, the microhardness of the base material value of 86 HV0.1 increased to about 110–125 HV0.1 in the stir zone depending on the used welding parameters. Due to lack of the strengthening phase and low strain hardening of used alloy the lack of a significantly softened zone was reported by both microhardness analysis and investigation of the fractured samples.

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Friction Stir Welding Parameters: Impact of Abnormal Grain Growth during Post-Weld Heat Treatment on Mechanical Properties of Al–Mg–Si Welded Joints

Metals ◽

10.3390/met10121607 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1607

Author(s):

Amir Hossein Baghdadi ◽

Zainuddin Sajuri ◽

Mohd Zaidi Omar ◽

Armin Rajabi

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Friction Stir Welding ◽

Grain Growth ◽

Precipitation Hardening ◽

Al Alloys ◽

Abnormal Grain Growth ◽

Post Weld Heat Treatment ◽

Welding Parameters ◽

Friction Stir

Friction stir welding (FSW) is an alternative method to join aluminum (Al) alloys in a solid-state condition. However, the coarsening or dissolution of precipitation hardening phases in the welding zone causes strength reduction or softening behavior in the welded area of age-hardened Al alloys. Therefore, this research aimed to improve the mechanical properties of an FSW Al–Mg–Si alloy via post-weld heat treatment (PWHT) and the possibility of controlling the abnormal grain growth (AGG) using different welding parameters. FSW was performed with different rotational and travel speeds, and T6 heat treatment was carried out on the FSW samples as the PWHT. The results showed a decrease in the strength of the FSW samples compared with that of the base material (BM) due to the dissolution of precipitation hardening particles in the heat-affected zone. However, the emergence of AGG in the microstructure after the T6-PWHT was identified as the potential event in the microstructure of the PWHT samples. It is found that the AGG of the microstructure in similar joints of Al6061(T6) was governed by the welding parameters. The results proved that PWHT was able to increase the tensile properties of the welded samples to values comparable to that of Al6061(T6)-BM. The increased mechanical properties of the FSW joints were attributed to a proper PWHT that resulted in a homogeneous distribution of the precipitation hardening phases in the welding zones.

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Mechanical Property of Friction Stir Welded Retardant Magnesium Alloy Joint

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.1929 ◽

2011 ◽

Vol 295-297 ◽

pp. 1929-1932

Author(s):

Yi Min Tu ◽

Ran Feng Qiu ◽

Hong Xin Shi ◽

Xin Zhang ◽

Ke Ke Zhang

Keyword(s):

Mechanical Properties ◽

Mechanical Property ◽

Friction Stir Welding ◽

Magnesium Alloy ◽

Welding Speed ◽

Rotational Speed ◽

Maximum Strength ◽

Welding Parameters ◽

Tool Rotational Speed ◽

Friction Stir

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.

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Influence of Tool Rotational Speed on the Mechanical Properties of Friction Stir Welded Al-Cu-Li Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.857.228 ◽

2016 ◽

Vol 857 ◽

pp. 228-231

Author(s):

Ho Sung Lee ◽

Ye Rim Lee ◽

Kyung Ju Min

Keyword(s):

Mechanical Properties ◽

Friction Stir Welding ◽

Space Shuttle ◽

Welding Process ◽

High Strength ◽

Fusion Welding ◽

Welding Parameters ◽

Friction Stir ◽

Mechanical And Microstructural Properties ◽

Tool Rotation

Aluminum-Lithium alloys have been found to exhibit superior mechanical properties as compared to the conventional aerospace aluminum alloys in terms of high strength, high modulus, low density, good corrosion resistance and fracture toughness at cryogenic temperatures. Even though they do not form low-melting eutectics during fusion welding, there are still problems like porosity, solidification cracking, and loss of lithium. This is why solid state friction stir welding is important in this alloy. It is known that using Al-Cu-Li alloy and friction stir welding to super lightweight external tank for space shuttle, significant weight reduction has been achieved. The objective of this paper is to investigate the effect of friction stir tool rotation speed on mechanical and microstructural properties of Al-Cu-Li alloy. The plates were joined with friction stir welding process using different tool rotation speeds (300-800 rpm) and welding speeds (120-420 mm/min), which are the two prime welding parameters in this process.

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EFFECT OF TOOL GEOMETRY AND WELDING PARAMETERS ON THE MECHANICAL PROPERTIES OF COMMERCIAL ALUMINUM WELD JOINTS BY FRICTION STIR WELDING

ERJ. Engineering Research Journal ◽

10.21608/erjm.2011.67273 ◽

2011 ◽

Vol 34 (2) ◽

pp. 205-214

Author(s):

M. A. ‌ Shaker ◽

A. El Baghdady ◽

S. Misbah

Keyword(s):

Mechanical Properties ◽

Friction Stir Welding ◽

Tool Geometry ◽

Welding Parameters ◽

Friction Stir ◽

Weld Joints

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Effect of welding parameters on mechanical properties and microstructure of friction stir welded brass joints

Matériaux & Techniques ◽

10.1051/mattech/2018060 ◽

2018 ◽

Vol 106 (6) ◽

pp. 606 ◽

Cited By ~ 1

Author(s):

İnan Geçmen ◽

Zarif Çatalgöl ◽

Mustafa Kemal Bilici

Keyword(s):

Mechanical Properties ◽

Friction Stir Welding ◽

Rotation Speed ◽

Stir Zone ◽

Weld Strength ◽

Welding Parameters ◽

Feed Speed ◽

Friction Stir ◽

Tool Rotation Speed ◽

Tool Rotation

Friction stir welding is a method developed for the welding of high-alloy aluminum materials which are difficult to combine with conventional welding methods. Friction stir welding of MS 63 (brass) plates used different tools (tapered cylindrical, tapered threaded cylindrical), tool rotational speeds (1040, 1500, 2080 rpm) and traverse speeds (30,45,75,113 mm.min−1). Tensile, bending, radiography and microstructure tests were carried out to determine the mechanical properties of brass plates joined by friction stir welding technique. Microstructure characterization studies were based on optical microscope and SEM analysis techniques. In addition, after joining operations, radiographs were taken to see the internal structure failure. Brass sheets were successfully joined to the forehead in the macrostructure study. In the evaluation of the microstructure, it was determined that there were four regions of base metal, thermomechanically affected zone (TMEB), heat-affected zone (HAZ) and stir zone. In both welding tools, the weld strength increased with increasing tool rotation speed. The particles in the stir zone are reduced by increasing of the tool rotation speed. Given the strength and % elongation values, the highest weld strength was achieved with tapered pin tool with a tool rotation speed of 1040 rpm and a tool feed speed of 113 min−1.

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