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Early steel bridges built around the world were generally protected against corrosion using paint; ordinary coatings provided protection for 3 to 5 years, while heavy-duty anti-corrosion coatings lasted 8 to 10 years. After that, repainting was required every 3 to 5 years, and the effectiveness of such maintenance measures was not satisfactory, and China was no exception. Historically, the damage caused by corrosion of painted and anti-corrosive steel bridges has been severe, and the costs associated with their anti-corrosive maintenance are enormous. Due to corrosion and the weathering of existing paint, a large number of steel bridges currently require maintenance, repair, and repainting. For this reason, whether it is new steel bridges being built or existing steel bridges in use, there is an urgent need for a long-lasting anti-corrosion coating with a lifespan of 30 to 50 years or more, so as to provide protection once applied and ensure that the steel bridges remain free from corrosion over time. In Europe, the transportation sector has been using long-lasting metal spray anti-corrosion coatings for over half a century. Countries such as the United States, the United Kingdom, Norway, and Sweden began to widely use zinc spraying and aluminum anti-corrosion coatings for bridge protection as early as the 1950s and 1960s ； China’s thermal spraying technology (especially arc spraying) has reached an internationally advanced level, yet this technology is rarely used for the anti-corrosion protection of steel bridges in the country. In our country, heavy-duty anti-corrosion paints are still widely used to protect steel bridges, and there is inevitably a significant gap between the designed service life of these bridges and their actual anti-corrosion lifespan. In recent years, **significant investment has been made in the construction of transportation infrastructure: 500 billion yuan has been invested in roads, and 250 billion yuan in railways. A large number of steel bridges need to be built over major rivers. For newly built bridges, only coatings that can provide excellent durability while causing the least impact on the environment are suitable for use. Thermal spray metal coatings have attracted the attention of bridge engineers due to their superior corrosion resistance and environmental adaptability. Since the 1990s, the arc spraying technology in our country has been further improved, which has significantly enhanced the quality of coatings and production efficiency while reducing production costs. It is widely used for long-term corrosion protection of steel structural elements, and its corrosion prevention effect is far superior to that of paint; it enables corrosion protection to last throughout the design life of steel bridges. The widespread application of arc spray coatings for long-term corrosion protection on steel bridges in our country will, over the coming decades, help to save substantial amounts of money on maintenance costs related to corrosion protection of these bridges. It will also reduce environmental pollution caused by paint-based corrosion protection methods, and extend the service life of steel bridges. This will undoubtedly bring about significant economic and social benefits.