Non-Destructive Testing (NDT) Direction
When dense porosity is found in NDT (especially UT), it is a very typical and serious quality issue. Systematic analysis of the root cause is crucial to avoid arbitrary conclusions and unnecessary rework.
Breakthrough Directions for Rare Earth Welding Wire
Although laboratory studies have fully demonstrated the significant potential of rare earth welding wire in improving weld microstructure, refining grain size, and enhancing toughness, its large-scale industrial application does face some practical bottlenecks.
The table below summarizes the main current industrialization bottlenecks.
Robotic automated welding
In summary, the core requirements can be summarized as “consistency” and “predictability.” Robots cannot adjust in real-time through feel or sight like skilled welders, so every characteristic of the welding wire must be highly stable to ensure a smooth welding process and uniform weld quality.
The following are the specific aspects of the higher requirements that robotic automated welding places on welding wire:
Diffused Hydrogen
To ensure welds achieve ultra-low hydrogen levels (≤5mL/100g) or even extremely low hydrogen levels (≤2mL/100g), the key lies in establishing a comprehensive control system covering welding material manufacturing, packaging and storage, and on-site construction. This system can effectively reduce the risk of hydrogen-induced cooling cracking and ensure the welding safety of high-strength steel structures.
Special Discussion: Welding Heat Input
Understanding the differences in heat input sensitivity between flux-cored and solid welding wires, and why strict heat input control is essential for high-strength steel welding, is fundamental to ensuring the welding quality of critical structures.
I. Flux-cored vs. Solid Welding Wire: Sensitivity to Heat Input ……
Why is “low-strength matching” often used when welding thick plates?
“Low-strength matching” refers to the use of welding materials (electrodes, wires, etc.) where the strength of the deposited metal is lower than the standard strength value of the base material. This is especially common in thick plate welding, and the underlying principles can be understood from both mechanical and metallurgical perspectives.
Weld integrity under extreme conditions
For structures operating under low-temperature (below -46°C) and high-temperature (>500°C) creep conditions, the requirements for welding materials are drastically different, but both are extremely stringent.
The following will elaborate on the most critical performance indicators and corresponding testing standards for these two areas.
Welding position refers to the spatial location of the weld during operation. It directly impacts welding difficulty, process selection, quality, and the skill requirements of the welder. Simply put, the welding challenges change depending on the position of the workpiece being welded (e.g., horizontal, vertical, overhead).
【Universidad ARCFORT】Explorando el “Metal de Aporte Super Austenítico”
Superaustenitic stainless steels: This is a high-end stainless steel developed to withstand harsher corrosive environments, such as those containing chloride ions. These stainless steels achieve exceptional corrosion resistance by significantly increasing the content of key alloying elements compared to conventional austenitic stainless steels. Key features include:
【ARCFORT University】Destructive Welding Test
Destructive welding testing is a core tool for welding quality control and process evaluation.
Destructive welding testing refers to a series of experimental methods that involve applying loads to weld joints through physical or mechanical methods until they fail, then inspecting and testing their performance to evaluate weld quality, process rationality, and material suitability.
Welding of Ultra-High Strength Steel
This is a core issue in welding engineering. When welding ultra-high strength steel, focusing solely on strength matching often leads to weld joint failure. Metallurgical compatibility is crucial for ensuring the safety and reliability of welded structures. Besides strength matching, the most critical metallurgical factors when selecting welding materials include the following:
What is the biggest challenge in selecting welding materials when welding dissimilar steels?
Welding P91 (martensitic heat-resistant steel) and 316L (austenitic stainless steel) is a classic and extremely challenging case in dissimilar steel welding. The biggest challenge in selecting welding materials can be summarized as a core contradiction: How to simultaneously address the significant differences in chemical composition, physical properties, and metallurgical behavior of the two base materials in a single weld joint, while ensuring the long-term safe operation of the joint under high-temperature and high-stress conditions.