Research status of titanium alloy micro-arc oxidation resistance to high temperature oxidation
Titanium alloys have high strength, hardness and corrosion resistance, but when titanium alloys are oxidized at high temperatures, problems such as surface oxidation and quality loss will occur. Micro-arc oxidation of titanium alloy is a common surface modification method, which can form a micro-arc oxidation layer with high hardness, wear resistance and insulation on the surface of titanium alloy, thereby improving the high-temperature oxidation performance of titanium alloy. This article discusses the current research status of micro-arc oxidation resistance of titanium alloys to high-temperature oxidation, including the morphological structure, physical and chemical properties of the micro-arc oxidation layer, and the mechanism by which the micro-arc oxidation layer enhances the high-temperature oxidation performance of titanium alloys.
1. Titanium alloy micro-arc oxidation resistance to high temperature oxidation
Titanium alloy has high strength, hardness and corrosion resistance, and is widely used in aviation, aerospace, medical equipment and other fields. However, when titanium alloys are oxidized at high temperatures, problems such as surface oxidation and quality loss may occur. Therefore, it is very important to improve the performance of titanium alloys under high temperature oxidation conditions.
Micro-arc oxidation is a common surface modification method that can form a micro-arc oxidation layer with high hardness, wear resistance and insulation on the surface of titanium alloy, thereby improving the high-temperature oxidation performance of titanium alloy. At present, the research on high-temperature oxidation resistance of titanium alloy micro-arc oxidation has formed a certain scale. This article aims to explore the current research status of titanium alloy micro-arc oxidation resistance to high-temperature oxidation.
2. Morphology and structure of micro-arc oxidation layer
Micro-arc oxidation is an electrochemical reaction produced by electric discharge in dielectric liquid. During the micro-arc oxidation process, a discharge arc is generated on the surface of the titanium alloy to form a micro-arc oxidation layer. The micro-arc oxidation layer has a complex morphological structure, including pores, cracks, particles, grains and other microstructures. Porosity is one of the most significant features in micro-arc oxidation layers, and the size and distribution of pores have an important impact on the performance of micro-arc oxidation layers. Cracks are also a common structure in micro-arc oxidation layers. The number and distribution of cracks will affect the uniformity and stability of micro-arc oxidation layers. Particles and grains are the basic components of the micro-arc oxidation layer. The size and shape of the particles and grains also have an important impact on the performance of the micro-arc oxidation layer.
3Physical and chemical properties
The micro-arc oxidation layer has some special physical and chemical properties, including high hardness, corrosion resistance, insulation and other properties. The hardness of the micro-arc oxidation layer reaches 500-1500HV, which can improve the wear resistance of the titanium alloy surface. In addition, the micro-arc oxidation layer also has good corrosion resistance and can protect the titanium alloy surface from being corroded by chemicals such as acids and alkalis. The insulation performance of the micro-arc oxidation layer is also very good, which can reduce the electromagnetic interference of titanium alloy parts to a certain extent.
4. The mechanism of micro-arc oxidation layer to enhance the high-temperature oxidation performance of titanium alloy. The micro-arc oxidation layer can improve the high-temperature oxidation performance of titanium alloy. Its main mechanism includes the following aspects:
(1) Stability of the micro-arc oxidation layer: The micro-arc oxidation layer can maintain its structure and performance stability, thereby protecting the titanium alloy surface from oxidation.
(2) Oxidation resistance of the micro-arc oxidation layer: The micro-arc oxidation layer will generate an oxide layer at high temperature. This oxide layer can prevent oxygen molecules from further penetrating into the surface of the titanium alloy, thereby reducing the degree of high-temperature oxidation.
(3) Chemical reaction of the micro-arc oxidation layer: The surface chemical reaction of the micro-arc oxidation layer can adsorb a certain amount of oxygen molecules, thereby reducing the contact between oxygen molecules and the surface of the titanium alloy, thereby reducing high-temperature oxidation.
5. Conclusion
Micro-arc oxidation of titanium alloy is an effective surface modification method, which can form a micro-arc oxidation layer with high hardness, wear resistance and insulation, and improve the high-temperature oxidation performance of titanium alloy. The morphological structure, physical and chemical properties of the micro-arc oxidation layer and the mechanism by which the micro-arc oxidation layer enhances the high-temperature oxidation performance of titanium alloys are important aspects of studying the high-temperature oxidation resistance of titanium alloys by micro-arc oxidation, and require further in-depth research and exploration.
