1,Tinplate tin sheet strip is an iron sheet with a layer of tin plated on the surface.Electrolytic tinplate steel in sheet is not easy to rust, and is also called tin-plated iron. Tin sheet strip is made by immersing an iron piece in molten tin. Tin is a metal that is less active than iron. It is neither oxidized by air nor reacted with water, so tin plate has a strong ability to resist corrosion. A thin layer of tin is plated on the iron sheet for good protection. However, once the coating is damaged and electrochemical corrosion occurs, because iron is more active than tin, iron will be lost as the negative electrode of the galvanic battery by oxidation reaction. The presence of tin will accelerate the corrosion rate of iron. Therefore, tin sheet strip is different from white iron. Only when the coating is intact can it protect the iron.
Electrolytic tinplate steel in sheet was first produced in Bohemia (in today's Czech Republic and Slovakia). The area has been rich in metal since ancient times, with advanced technology and know how to use water power to engage in machine manufacturing. Tin plate has been produced since the 14th century. For a long period of time, this place has always been the main producing area of tin sheet strip in the world. At that time, tin sheet strip was mainly used to make tableware and drinking utensils. In the 17th century, Britain, France, and Sweden all hoped to establish their own tin plate industries, but due to the need for large amounts of funds, they have not been developed for a long time. It was not until 1811 that Brian Donkin and John Hall started tin plate canned food that tin sheet strip manufacturing developed on a large scale. Today, the world produces about 250,000 tons of tin annually, and more than one-third is used to make tin sheet strip, most of which is used in the canned food industry.
2. Hardness test of tin sheet strip
In the past, the hardness test of tin sheet strip mostly used the desktop surface Rockwell hardness tester, and the ordinary tin plate test anvil was used to test the HR30T hardness.
In recent years, since the national standard GB/T2520-2000 for tin plate has adopted the internationally accepted HR30Tm hardness representation method, diamond anvils have been used in China to test the HR30Tm hardness value of electrolytic tinplate steel in sheet.