Microstructural refinement mechanism and its effect on toughness in the nugget zone of high-strength pipeline steel by friction stir welding

2021 ◽  
Author(s):  
R.H. Duan ◽  
G.M. Xie ◽  
P. Xue ◽  
Z.Y. Ma ◽  
Z.A. Luo ◽  
...  
Keyword(s):  
Friction Stir Welding ◽  
Pipeline Steel ◽  
High Strength ◽  
Nugget Zone ◽  
Microstructural Refinement ◽  
Friction Stir ◽  
Refinement Mechanism

Mechanical and Corrosion Behavior of Friction Stir Welded AA 6063 Alloy

2022 ◽  
pp. 206-214
Author(s):  
Radha R. ◽  
Sreekanth D. ◽  
Tushar Bohra ◽  
Surya Bhan Pratap Singh
Keyword(s):  
Friction Stir Welding ◽  
High Strength ◽  
Metallic Alloys ◽  
Fusion Welding ◽  
Corrosion Properties ◽  
Microstructural Refinement ◽  
Significant Development ◽  
Friction Stir ◽  
Mechanical And Corrosion Properties ◽  
Fsw Parameters

Friction stir welding (FSW) is considered to be the most significant development in solid state metal joining processes. This joining technique is energy efficient, environmentally friendly, and versatile. In particular, it can be used to join high-strength aerospace aluminum alloys and other metallic alloys that are hard to weld by conventional fusion welding. The project aims to join Aluminum 6063 alloy plates by FSW and emphasize the (1) mechanisms responsible for the formation of welds without any defects, microstructural refinement, and (2) effects of FSW parameters on resultant microstructure, mechanical, and corrosion properties.

Microstructure, crystallography, and toughness in nugget zone of friction stir welded high-strength pipeline steel

2020 ◽  
Vol 791 ◽  
pp. 139620 ◽  
Author(s):  
R.H. Duan ◽  
G.M. Xie ◽  
Z.A. Luo ◽  
P. Xue ◽  
C. Wang ◽  
...  
Keyword(s):  
Pipeline Steel ◽  
High Strength ◽  
Nugget Zone ◽  
Friction Stir

scholarly journals Effect of Stirring Pin Rotation Speed on Microstructure and Mechanical Properties of 2A14-T4 Alloy T-Joints Produced by Stationary Shoulder Friction Stir Welding

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1938
Author(s):  
Haifeng Yang ◽  
Hongyun Zhao ◽  
Xinxin Xu ◽  
Li Zhou ◽  
Huihui Zhao ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Friction Stir Welding ◽  
Rotation Speed ◽  
Weld Nugget ◽  
Al Alloy ◽  
Nugget Zone ◽  
T Joints ◽  
Friction Stir ◽  
Stationary Shoulder ◽  
Microstructure And Mechanical Properties

In this study, 2A14-T4 Al-alloy T-joints were prepared via stationary shoulder friction stir welding (SSFSW) technology where the stirring pin’s rotation speed was set as different values. In combination with the numerical simulation results, the macro-forming, microstructure, and mechanical properties of the joints under different welding conditions were analyzed. The results show that the thermal cycle curves in the SSFSW process are featured by a steep climb and slow decreasing variation trends. As the stirring pin’s rotation speed increased, the grooves on the weld surface became more obvious. The base and rib plates exhibit W- or N-shaped hardness distribution patterns. The hardness of the weld nugget zone (WNZ) was high but was lower than that of the base material. The second weld’s annealing effect contributed to the precipitation and coarsening of the precipitated phase in the first weld nugget zone (WNZ1). The hardness of the heat affect zone (HAZ) in the vicinity of the thermo-mechanically affected zone (TMAZ) dropped to the minimum. As the stirring pin's rotation speed increased, the tensile strengths of the base and rib plates first increased and then dropped. The base and rib plates exhibited ductile and brittle/ductile fracture patterns, respectively.

Study of the Key Issues of Friction Stir Welding of Titanium Alloy

2010 ◽  
Vol 638-642 ◽  
pp. 1185-1190 ◽  
Author(s):  
Hui Jie Liu ◽  
Li Zhou ◽  
Yong Xian Huang ◽  
Qi Wei Liu
Keyword(s):  
Titanium Alloy ◽  
Friction Stir Welding ◽  
Melting Point ◽  
Titanium Alloys ◽  
Welding Process ◽  
High Strength ◽  
Liquid Cooling ◽  
Friction Stir ◽  
Key Issues ◽  
Aluminum And Magnesium Alloys

As a new solid-state welding process, friction stir welding (FSW) has been successfully used for joining low melting point materials such as aluminum and magnesium alloys, but the FSW of high melting point materials such as steels and titanium alloys is still difficult to carry out because of their strict requirements for the FSW tool. Especially for the FSW of titanium alloys, some key technological issues need to solve further. In order to accomplish the FSW of titanium alloys, a specially designed tool system was made. The system was composed of W-Re pin tool, liquid cooling holder and shielding gas shroud. Prior to FSW, the Ti-6Al-4V alloy plates were thermo-hydrogen processed to reduce the deformation resistance and tool wear during the FSW. Based on this, the thermo-hydrogen processed Ti-6Al-4V alloy with different hydrogen content was friction stir welded, and the microstructural characterizations and mechanical properties of the joints were studied. Experimental results showed that the designed tool system can fulfill the requirements of the FSW of titanium alloys, and excellent weld formation and high-strength joint have been obtained from the titanium alloy plates.

Effect of plasma preheating on weld quality and tool life during friction stir welding of DH36 steel

2021 ◽  
pp. 095440542199013
Author(s):  
Avinish Tiwari ◽  
Pardeep Pankaj ◽  
Saurav Suman ◽  
Piyush Singh ◽  
Pankaj Biswas ◽  
...  
Keyword(s):  
Friction Stir Welding ◽  
Tool Life ◽  
Force Measurement ◽  
Deep Understanding ◽  
High Strength ◽  
Microstructural Characterization ◽  
Stir Zone ◽  
Friction Stir ◽  
Allotriomorphic Ferrite ◽  
Fsw Parameters

Friction stir welding (FSW) of high strength materials is challenging due to high tool cost and low tool life. To address this issue, the present investigation deals with an alternative of plasma-assisted friction stir welding (PFSW) of DH36 steel with WC-10%Co tool. Plasma preheating current (13 A, 15 A, and 17 A) was varied by keeping other FSW parameters as constant. During the FSW and PFSW process, force measurement and thermal history aided in a deep understanding of the process, tool degradation mechanisms, accompanied by the mechanical and microstructural characterization of the welded joints. The stir zone hardness was increased from 140 HV0.5 to about 267 HV0.5. The yield and tensile strength of weld increased from 385 MPa and 514 MPa to about 391 MPa and 539 MPa, respectively. Weld joint elongation (%) was increased from ~10% of weld 1 to ~13.89% of weld 4. During PFSW, the process temperature was increased, the cooling rate was lowered, and the weld bead was widened. The results also revealed that the plasma-assisted weld resulted in polygonal ([Formula: see text]) and allotriomorphic ferrite as the major constituents in the stir zone. Pearlite dissolution and spheroidization were observed in the ICHAZ and SCHAZ, respectively. Additionally, the plasma preheating reduced the tungsten tool’s wear by 58% compared to FSW.

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>

Microstructure and Mechanical Properties of a Friction Stir Processed Al-Zn-Mg-Cu Alloy

2010 ◽  
Vol 654-656 ◽  
pp. 1428-1431 ◽  
Author(s):  
Margarita Vargas ◽  
Sri Lathabai
Keyword(s):  
Mechanical Properties ◽  
Rotational Speed ◽  
High Strength ◽  
Travel Speed ◽  
Nugget Zone ◽  
Friction Stir ◽  
Complex Interactions ◽  
Cu Alloy ◽  
Microstructure And Mechanical Properties ◽  
Aa 7075

Friction stir processing (FSP) was performed on AA 7075-T6, a heat treatable high strength Al-Zn-Mg-Cu alloy. The two main FSP parameters, the tool rotational and travel speed, were varied systematically in order to understand their influence on the microstructure and mechanical properties of the processed zone. At a given rotational speed, increasing the travel speed increased the microhardness of the nugget (stir) zone; for a given travel speed there appeared to be an optimum rotational speed which resulted in the highest microhardness. The range of FSP parameters used did not significantly influence the nugget zone grain size. It is suggested that the observed mechanical properties are a result of the complex interactions between the FSP thermo-mechanical effects and the processes of dissolution, coarsening and re-precipitation of the strengthening precipitates in this alloy.

On the problem of tool destruction when obtaining fixed joints of thick-walled aluminum alloy blanks by friction welding with mixing

2021 ◽  
Vol 23 (3) ◽  
pp. 72-83
Author(s):  
Kirill Kalashnikov ◽  
◽  
Andrey Chumaevskii ◽  
Tatiana Kalashnikova ◽  
Aleksey Ivanov ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Friction Stir Welding ◽  
Friction Welding ◽  
Welding Process ◽  
High Strength ◽  
Heterogeneous Structure ◽  
Adhesive Interaction ◽  
Friction Stir ◽  
Tool Shoulder ◽  
Electric Erosion

Introduction. Among the technologies for manufacturing rocket and aircraft bodies, marine vessels, and vehicles, currently, more and more attention is paid to the technology of friction stir welding (FSW). First of all, the use of this technology is necessary where it is required to produce fixed joints of high-strength aluminum alloys. In this case, special attention should be paid to welding thick-walled blanks, as fixed joints with a thickness of 30.0 mm or more are the target products in the rocket-space and aviation industries. At the same time, it is most prone to the formation of defects due to uneven heat distribution throughout the height of the blank. It can lead to a violation of the adhesive interaction between the weld metal and the tool and can even lead to a destruction of the welding tool. The purpose of this work is to reveal regularities of welding tool destruction depending on parameters of friction stir welding process of aluminum alloy AA5056 fixed joints with a thickness of 35.0 mm. Following research methods were used in the work: the obtaining of fixed joints was carried out by friction welding with mixing, the production of samples for research was carried out by electric erosion cutting, the study of samples was carried out using optical metallography methods. Results and discussion. As a result of performed studies, it is revealed that samples of aluminum alloy with a thickness of 35.0 mm have a heterogeneous structure through the height of weld. There are the tool shoulder effect zone and the pin effect zone, in which certain whirling of weld material caused by the presence of grooves on tool surface is distinctly distinguished. It is shown that the zone of shoulders effect is the most exposed to the formation of tunnel-type defects because of low loading force and high welding speeds. It is revealed that tool destruction occurs tangentially to the surface of the tool grooves due to the high tool load and high welding speeds.

Control of Material Flow During Friction Stir Welding Between Aluminum and Steel by Welding Tool Shape

2020 ◽  
Author(s):  
Toshiaki Yasui ◽  
Yuki Ogura ◽  
Xu Huilin ◽  
F. Farrah Najwa ◽  
Daichi Sugimoto ◽  
...  
Keyword(s):  
Friction Stir Welding ◽  
Material Flow ◽  
Simulation Experiment ◽  
Low Cost ◽  
Flow Analysis ◽  
Material Flow Analysis ◽  
High Strength ◽  
Friction Stir ◽  
Tool Shape ◽  
Computational Fluid Dynamics Cfd

Abstract For the Friction stir welding (FSW) between aluminum and steel is important to fabricate vehicles with light weight and high strength for safety at low cost. For the fabrication of sound weld, it is necessary to control the material flow during FSW. In this study, the material flow during FSW was elucidated by numerical simulation by computational fluid dynamics (CFD) analysis and simulation experiment by transparent Poly-vinyle chloride (PVC) as simulant of aluminum and tracer material. Based on this material flow analysis, several shapes of welding tool were examined for control of material flow during FSW. Scroll shoulder is effective for enhancement of stirring zone by increasing material velocity around the probe. Flute and fine screw probe promote the material flow in depth and horizontal direction. The welding tool with scroll shoulder and flute and fine screw probe achieved sound weld with highest tensile strength of 120.4 MPa.

Sign in / Sign up

Export Citation Format

Share Document