Effect of welding parameters on porosity distribution of dual laser beam bilateral synchronous welding in 2219 aluminum alloy T-joint

This paper presents the laser beam welding process of a lap joint between galvanized steel (Z225) and an aluminum alloy (A6000) from an IPG fiber laser. Welding of steel to aluminum has become popular in the automotive industry as a means of reducing the total vehicle body mass. This approach reduces fuel consumption and, ultimately, carbon emissions. Laser welding parameters used to control heat input for the study were laser power ranging between 800 and 1200 W, as well as laser welding speeds between 2 and 4 m/min. Distinct features of the dissimilar joints were microscopically examined. The SEM-EDS technique was employed to study the intermetallic phases along the Fe-Al interface. The outcome revealed the presence of “needle-like phases” and “island-shaped phases” at high heat inputs. Traces of both Fe2Al5 and FeAl3 phases were detected. For low heat input, there was evidence of insufficient fusion. Weld width was influenced by welding parameters and increased with an increase in heat input. Mechanical properties of the joints indicated that the microhardness values of the weld joints were higher than those of both base metals. The maximum tensile shear strength obtained was 1.79 kN for a sample produced at 1200 W and 3 m/min.

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Welding Parameters Optimization in Plunging and Dwelling Phase of FSW Medium Thickness 2219 Aluminum Alloy

10.21203/rs.3.rs-1131926/v1 ◽

2021 ◽

Author(s):

Xiaohong Lu ◽

Jinhui Qiao ◽

Junyu Qian ◽

Shixuan Sun ◽

Steven Y. Liang

Keyword(s):

Aluminum Alloy ◽

Temperature Distribution ◽

Simulation Model ◽

Rotational Speed ◽

Parameters Optimization ◽

Welding Parameters ◽

Medium Thickness ◽

Dwelling Time ◽

Friction Stir ◽

2219 Aluminum Alloy

Abstract The influence of welding parameters on temperature distribution in plunging and dwelling phase of friction stir welding (FSW) medium thickness 2219 aluminum alloy is blank. Improper selection of welding parameters will result in uneven temperature distribution along the thickness of the weldment, which will lead to welding defects and ultimately affect the mechanical properties of the weldment. To realize the prediction of temperature distribution and achieve the optimization of welding parameters, a simulation model of FSW 18mm thick 2219 aluminum alloy is built based on DEFORM. The validity of the simulation model is verified by temperature measurement experiments. With the minimum temperature difference in the core area of the weldment as target value, and weldable temperature range of 2219 aluminum alloy as constraint conditions, orthogonal experiments are conducted considering the rotational speed, the press amount, the tool tilt angle, the plunging traverse speed and the dwelling time. The results of variance analysis show that the rotational speed and the dwelling time are significant factors affecting temperature field during plunging and dwelling phase. Through single factor simulation, the welding parameters in plunging and dwelling phase are optimized. This study provides a reference for realizing high-quality welding of a heavy rocket fuel tank.

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