# Methodology to Reduce Distortion Using a Hybrid Thermal Welding Process

^{1}

^{2}

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Method Details

## 3. Methodology

^{2}) was defined for the exterior surfaces of the assembly. The model was built using the ESI.Syweld software (2014, ESI Group, Paris, France).

- The heatline forming process using a heatline laser diode was applied over small plates (300 × 200 mm) with two thickness values (6 and 8 mm) under different power density configurations. The assembly chosen was a cantilever-like structure. The laser scanning was performed in the middle line of the plate;
- The propane gas static heating process characterization was performed, using a heating propane torch over a vertical plate. The heating of the heatprint and the cooling the plate were analyzed;
- Weld process characterization over a large T-joint using a FCAW (flux cored arc welding) process. The tests were performed with continuum and double-sided welds. Every sample used was three meters long. The thickness values chosen were 8 mm for the web and 12 mm for the flange.

## 4. Results

## 5. Discussion

## 6. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Schematic of the manufacturing process with the size of the T-joint. (dimensions in mm). (

**a**) Distance between process torches; (

**b**) P1 geometry; (

**c**) P2 geometry.

**Figure 2.**Experimental procedures, (

**a**) heatline laser forming process; (

**b**) propane heating process; (

**c**) flux cored arc welding (FCAW) welding process.

**Figure 5.**Vertical deflection comparison against torch temperature and torch position parametrization.

**Figure 6.**(

**a**) Measurement points for the residual stresses; (

**b**) Residual stresses over the measurement line for thermal transient tensioning (TTT)-HL283.

**Figure 7.**(

**a**) Stresses distribution during the high-temperature TTT (htTTT) process (MPa); (

**b**) stress distribution during the process.

**Figure 8.**(

**a**) Longitudinal residual stresses for different locations of the additional heat source (Figure 3a); (

**b**) schematic superposition of residual stresses from FCAW welding and an additional heat source.

**Figure 9.**(

**a**) Residual stresses for several htTTT tests; (

**b**) stress comparison along the measurement line (Figure 3a).

**Figure 10.**(

**a**) P2 distortion results on the reference non-symmetrical weld (mm); (

**b**) results of the distortion with htTTT.

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**MDPI and ACS Style**

Souto, J.; Ares, E.; Alegre, P.; Cerqueiro, J.
Methodology to Reduce Distortion Using a Hybrid Thermal Welding Process. *Materials* **2018**, *11*, 1649.
https://doi.org/10.3390/ma11091649

**AMA Style**

Souto J, Ares E, Alegre P, Cerqueiro J.
Methodology to Reduce Distortion Using a Hybrid Thermal Welding Process. *Materials*. 2018; 11(9):1649.
https://doi.org/10.3390/ma11091649

**Chicago/Turabian Style**

Souto, Javier, Enrique Ares, Paulino Alegre, and Jorge Cerqueiro.
2018. "Methodology to Reduce Distortion Using a Hybrid Thermal Welding Process" *Materials* 11, no. 9: 1649.
https://doi.org/10.3390/ma11091649