What is High-Temperature Corrosion? A Comprehensive Analysis of Causes, Hazards

In the field of industrial production, the safe operation of equipment under high-temperature conditions has always been a core concern. High-temperature corrosion, as a key factor restricting equipment service life and affecting production efficiency, has long been highly valued in industries such as metallurgy, chemical engineering, electric power, and machinery.

Especially for core transmission components such as bearings, once corrosion occurs under high-temperature conditions, it will not only lead to reduced equipment accuracy and frequent failures, but may also cause shutdown accidents, resulting in huge economic losses. This article provides a comprehensive explanation of what high-temperature corrosion is, explores its causes and hazards, and offers scientific protection solutions based on industrial practices, serving as a practical reference for professionals in the industrial field.

I. What Is High-Temperature Corrosion? Core Definition and Nature

High-temperature corrosion refers to the phenomenon in which metal or non-metallic materials undergo chemical or electrochemical reactions with surrounding media (such as gases, molten salts, or liquid metals) in high-temperature environments (typically above 500℃), resulting in surface damage, performance degradation, or even material failure. Essentially, high-temperature corrosion is the accelerated oxidation, sulfidation, carburization, and other reactions caused by high-temperature conditions, with reaction rates far higher than ordinary corrosion at room temperature.

In industrial production, high-temperature corrosion is widely present: boiler furnace tube walls, gas turbine blades, metallurgical furnace linings, and high-temperature bearing components may all face the threat of high-temperature corrosion. Compared with normal temperature corrosion, high-temperature corrosion mechanisms are more complex, influenced by temperature, media composition, and material characteristics. The damage is often irreversible and more destructive. Understanding high-temperature corrosion is the foundation for developing effective protection strategies and is essential for industrial equipment operation and maintenance management.

II. Main Types of High-Temperature Corrosion and Industrial Application Scenarios

In different industrial scenarios, high-temperature corrosion exhibits diverse forms and corrosive media. Identifying corrosion types helps accurately diagnose the causes and adopt targeted protection measures. The common types of high-temperature corrosion include:

These types of high-temperature corrosion often overlap in industrial production, further intensifying equipment damage. Precision components such as bearings are more affected due to their complex structure and high accuracy requirements.

III. Core Causes of High-Temperature Corrosion

High-temperature corrosion does not result from a single factor but is caused by the combined effect of temperature, medium, and material. Understanding these causes is the key to reducing corrosion risks at their root:

IV. Serious Hazards of High-Temperature Corrosion in Industrial Production

High-temperature corrosion shortens equipment service life and triggers safety and economic risks. Its main hazards include:

4.1 Reduced Equipment Lifespan and Increased Maintenance Costs

High-temperature corrosion causes thinning, wear, and cracking of equipment surfaces, forcing early component replacement and increasing maintenance cost. For example, bearing corrosion at high temperatures results in raceway wear and rolling element failure. An industrial-grade high-temperature bearing may cost tens of thousands of yuan, and replacement requires downtime, further reducing production capacity.

4.2 Reduced Production Efficiency and Product Quality

Corrosion reduces equipment accuracy and performance. High-temperature bearing corrosion affects transmission precision and product dimensional accuracy. Boiler tube corrosion reduces heat transfer efficiency, increases energy consumption, and undermines production stability.

4.3 Safety Accidents and Threats to Personnel

When high-temperature corrosion reduces critical component thickness below safety limits (e.g., boiler tubes or pressure vessels), leakage or explosion accidents may occur, threatening personnel safety and causing environmental damage.

V. Effective Protection Measures Against High-Temperature Corrosion

Based on the causes and hazards of high-temperature corrosion, protection can be implemented through multiple strategies:

5.1 Select Materials Resistant to High-Temperature Corrosion

Prefer stainless steels, superalloys, and ceramic matrix composites for components such as bearings, blades, and furnace linings. High-temperature bearing steel with chromium and molybdenum is recommended to improve oxidation and sulfidation resistance.

5.2 Surface Coating Protection

Use spraying, electroplating, CVD, and other technologies to form dense protective coatings. Common coatings include alumina, chromia, and metal-ceramic coatings, improving corrosion resistance by 3–5 times.

5.3 Optimize Processes and Operating Environments

Reduce corrosive media content through flue gas desulfurization and denitrification. Control temperature, avoid long-term extreme heat, and regularly remove ash and scale to reduce localized corrosion.

5.4 Improve Monitoring and Maintenance

Use infrared thermography, ultrasonic inspection, and other techniques for corrosion monitoring. Establish maintenance plans, remove rust, and renew protective coatings to ensure long-term integrity.

High-temperature corrosion is an unavoidable industrial challenge. Understanding its mechanisms, causes, hazards, and protection strategies is critical to ensuring safe equipment operation, reducing costs, and improving production efficiency. With ongoing advances in industrial technology, developments in high-temperature corrosion-resistant materials and protective coatings will provide more solutions for high-temperature corrosion prevention.