Short answer

When welding structural steel for demanding applications like offshore wind, designers must not only consider the increased tensile strength but also proactively manage the introduced distortion and residual stresses to ensure long-term fatigue resistance.

Field: Final Production
Source: Fatigue & Fracture of Engineering Materials & Structures (2025)
Method: Experimental investigation combined with modeling and image analysis.
Evidence: Strong effect

While submerged arc welding of S355G10+M steel for offshore wind applications increases ultimate tensile strength, it also introduces distortion and residual stresses that can negatively impact fatigue performance. This final production research insight is drawn from a 2025 study published in Fatigue & Fracture of Engineering Materials & Structures. Using Experimental investigation combined with modeling and image analysis., researchers explored how this design variable affects real-world outcomes. The key design takeaway: When welding structural steel for demanding applications like offshore wind, designers must not only consider the increased tensile strength but also proactively manage the introduced distortion and residual stresses to ensure long-term fatigue resistance.

Study

Final ProductionNew This WeekStrong effect

Submerged Arc Welding of S355G10+M Steel Enhances Tensile Strength but Introduces Distortion and Residual Stresses Affecting Fatigue

Fatigue & Fracture of Engineering Materials & Structures · 2025

Key Findings

01Welded sections exhibited greater ultimate tensile strength than the base material.
02Welded sections showed lower yield strength compared to the base material.
03Hardness and residual stresses correlated with plate thickness.
04A potential weak point was identified at the heat-affected zone (HAZ) and base material transition.
05Angular distortions, axial misalignments, stress concentrations, and residual stresses were found to influence fatigue performance.

Application

Design takeaway

How to apply

In the design phase for offshore wind structures, incorporate post-weld heat treatment or controlled cooling strategies to reduce residual stresses. Utilize finite element analysis to predict distortion and stress concentrations, guiding weld sequencing and joint design.

Project actions

01When investigating welding processes, consider how different parameters affect not just strength but also geometric accuracy and internal stresses.
02Document any observed distortions or signs of stress concentration meticulously, as these are critical performance factors.

Method & Evidence

AimTo analyze the impact of submerged arc welding on the strength, ductility, hardness, distortion, residual stresses, and fatigue performance of S355G10+M structural steel intended for offshore wind turbine applications.

MethodExperimental investigation combined with modeling and image analysis.

ProcedureS355G10+M steel plates of varying thicknesses were welded using a submerged arc welding process with a double V-groove and multi-pass technique. Mechanical properties (tensile strength, ductility, hardness), distortion, residual stresses, and fatigue performance were then experimentally evaluated and analyzed.

ContextOffshore wind turbine structural components (tower and monopile).

Variables

IV["Welding process (Submerged Arc Welding)","Plate thickness","Weld joint type (Double V-groove)","Multi-pass technique"]

DV["Ultimate tensile strength","Yield strength","Ductility","Hardness","Angular distortion","Axial misalignment","Residual stresses","Fatigue performance"]

CV["Steel grade (S355G10+M)","Welding consumables","Welding parameters (e.g., current, voltage, travel speed - if kept constant across some tests)"]

Strengths & Limitations

Strengths

+Comprehensive analysis of multiple material performance aspects (strength, distortion, stress, fatigue).
+Direct relevance to a critical industrial application (offshore wind turbines).

Limitations

The complexity of simulating real-world offshore conditions and the cost of extensive material testing can limit the scope of practical investigations.

Reliability & validity

The study's validity is supported by combining experimental testing with modeling. Reliability would depend on the number of replicate tests performed for each measurement and the consistency of the welding process.

Think critically

To what extent can post-weld treatments or alternative welding techniques fully mitigate the negative effects of distortion and residual stress without compromising the observed gains in tensile strength?

Design Principles

"Optimize welding processes to minimize distortion and residual stresses while maximizing beneficial material property enhancements for critical structural applications."

Understanding the trade-offs between weld strength enhancement and the introduction of detrimental factors like distortion and residual stress is crucial for ensuring the long-term structural integrity and safety of offshore wind turbine components. This knowledge informs material selection, welding process optimization, and design considerations to mitigate potential failure modes.

What This Means for Your Design

When you weld metal for big projects like wind turbines, it gets stronger in some ways, but it can also bend or warp, and internal stresses build up. These issues can make it more likely to break over time, so you need to be careful about how you weld it.

How to use in your project

1.Reference this study when discussing the trade-offs between material strength and the impact of manufacturing processes like welding on structural integrity and fatigue life in your design project.

Add to My Project

Quick Cite

Paragraph starter

The investigation into submerged arc welding of S355G10+M steel for offshore wind applications reveals that while the process enhances ultimate tensile strength, it concurrently introduces distortion and residual stresses. These factors, particularly concentrated in the heat-affected zone, are critical determinants of fatigue performance and must be carefully managed during the design and fabrication stages to ensure structural integrity.

Source

Fatigue & Fracture of Engineering Materials & Structures

Submerged Arc Welding of S355G10+M Steel: Analyzing Strength, Distortion, Residual Stresses, and Fatigue for Offshore Wind Applications

journal · 2025

View source

Questions About This Research

What does the research say about submerged arc welding of s355g10+m steel enhances tensile strength but introduces distortion and residual stresses affecting fatigue?: When welding structural steel for demanding applications like offshore wind, designers must not only consider the increased tensile strength but also proactively manage the introduced distortion and residual stresses to ensure long-term fatigue resistance. Evidence: Fatigue & Fracture of Engineering Materials & Structures (2025).
Why does "Submerged Arc Welding of S355G10+M Steel Enhances Tensile Strength but Introduces Distortion and Residual Stresses Affecting Fatigue" matter for design?: Understanding the trade-offs between weld strength enhancement and the introduction of detrimental factors like distortion and residual stress is crucial for ensuring the long-term structural integrity and safety of offshore wind turbine components. This knowledge informs material selection, welding process optimization, and design considerations to mitigate potential failure modes.
How can designers apply this research?: When welding structural steel for demanding applications like offshore wind, designers must not only consider the increased tensile strength but also proactively manage the introduced distortion and residual stresses to ensure long-term fatigue resistance.
What were the main findings?: Welded sections exhibited greater ultimate tensile strength than the base material.. Welded sections showed lower yield strength compared to the base material.. Hardness and residual stresses correlated with plate thickness.. A potential weak point was identified at the heat-affected zone (HAZ) and base material transition.
What research method was used?: Experimental investigation combined with modeling and image analysis..
How strong is the evidence?: Evidence strength is rated Strong effect, based on a 2025 journal from Fatigue & Fracture of Engineering Materials & Structures.
What should I do differently in my next project?: In the design phase for offshore wind structures, incorporate post-weld heat treatment or controlled cooling strategies to reduce residual stresses. Utilize finite element analysis to predict distortion and stress concentrations, guiding weld sequencing and joint design.
What are the limitations?: The study focused on a specific steel grade (S355G10+M) and welding process (SAW); findings may not be directly transferable to other materials or welding techniques. The long-term performance under actual offshore environmental conditions was not fully simulated.