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The American Welding Society conducted industrial coupon tests on zinc and aluminum thermal spray coatings over a period of 19 years in three types of environments: industrial environments, seawater environments (partially submerged in still seawater and fully submerged in flowing seawater), and marine environments. A total of 4,248 coupons were used in these tests, and the results showed that both zinc and aluminum coatings, when combined with sealing coatings, could provide long-term and effective corrosion protection for steel structural components in these three types of environments. The world-renowned 19-year test report on thermal spraying, AWSC2 14-74, was published as a result of these studies. The performance test reports on anti-corrosion coatings over 34 years in marine atmospheres, prepared by the LAQUE Corrosion Technology Center in the United States, confirm that thermally sprayed zinc and aluminum coatings remain effective in various hostile environments over the long term. Based on these findings, along with reports from 19 years of research, the U.S. developed the AWSC2 18-93 guidelines for thermally spraying processes, which serve as a quality control manual for companies engaged in thermally spraying operations, aiming to guide production processes. The U.S. Navy Civil Engineering Laboratory conducted 10-year tests on zinc- and aluminum-coated surfaces with a thickness of 75 μm in marine climates and seawater, and no red rust was observed, proving the effectiveness of these coatings in preventing corrosion. The French Metro company conducted 10-year exposure tests on zinc and aluminum coatings, and the results showed that they were effective in preventing corrosion. Tests on underground mines in Tbilisi, former Soviet Union, showed that zinc spraying for corrosion protection provides at least 30 years of corrosion resistance. The test results of different **technicians are consistent. Immediate thermal spraying of zinc and aluminum coatings can both provide long-term and effective protection for steel in marine atmospheres, industrial atmospheres, and seawater environments. These test results were directly used as the basis for formulating standards for thermal spraying anti-corrosion techniques, and they played a key role in promoting the use of thermal spraying anti-corrosion on large steel bridges in developed countries around the world after the 1960s, making a significant contribution to the development of thermal spraying worldwide.