Is The Mesh Belt Of The Heat Treatment Normalizing Furnace Prone To Hydrogen Embrittlement? What Causes This?

During the heat treatment normalizing process, the fracture of metal mesh belts not only leads to frequent downtime and increased maintenance costs, but also affects production progress. Today, Jiaoyang Mesh Belt will explore the causes of hydrogen embrittlement in normalizing furnace mesh belts with everyone, to ensure the stable operation of normalizing furnaces.

1. Precise traceability: main causes of hydrogen embrittlement fracture

Hydrogen embrittlement fracture is not accidental, but rather the result of the combined effects of hydrogen atom accumulation and external conditions. Through extensive case analysis, Jiaoyang has identified three core contributing factors:

The dew point of the furnace gas is out of control

In pursuit of a bright workpiece finish, excessively lowering the dew point results in insufficient water vapor within the furnace, which cannot "neutralize" the protective atmosphere. Over time, this accumulation exceeds the critical threshold.

Improper preprocessing of workpiece

If the workpiece is not cleaned thoroughly before entering the normalizing furnace, the residual oil, cutting fluid, moisture, etc. on its surface will decompose and generate a large amount of hydrogen at high temperatures.

The equipment is not sealed properly

Improper adjustment of the combustion system in the normalizing furnace (such as an improper air/gas ratio, leading to incomplete combustion) can generate a large amount of water vapor and incomplete combustion products, and may also increase the local hydrogen content within the furnace.

Why did it start to break after a few months?

The accumulation process of hydrogen

During daily operation, hydrogen atoms continuously enter the steel. A few months of operation is sufficient for the hydrogen content in the mesh belt to accumulate to a dangerous threshold.

The effect of stress

The mesh belt, enduring tensile and bending stresses at high temperatures, not only provides a site for hydrogen enrichment but also promotes the formation of cracks.

Fatigue and creep

The operation of the mesh belt is cyclic, and it is exposed to high temperatures for extended periods, leading to a combined effect of thermomechanical fatigue and creep.

3. Improvement of Jiaoyang Craftsmanship

Regarding the mechanism of hydrogen embrittlement in the mesh belt of the normalizing furnace, Jiaoyang has achieved breakthroughs from material selection to process optimization:

Carefully selected materials resistant to hydrogen embrittlement

High-quality stainless steels such as 310S and 314, which have undergone special heat treatment (all supporting traceability), are selected to enhance the material's resistance to brittleness while maintaining high temperature tolerance, making the mesh belt more durable.

Innovative molding process

Taking into account various factors such as the size of the workpiece, the usage environment, and specific customer requirements, Jiaoyang adopts a balanced/herringbone weaving process. The mesh belt structure is dense and uniform, reducing stress concentration points and extending the service life of the mesh belt.

Full-cycle service enhancement

Establish a 24-hour technical response mechanism to provide remote guidance or on-site troubleshooting for issues related to mesh belt operation;

Regularly provide maintenance suggestions to reduce the risk of hydrogen embrittlement throughout the entire process.