Tinplate Hardness Testing

1, what is tinplate

Tinplate is a tin plate coated with a layer of tin on the surface. It is not easy to rust and is also called tinplate. Iron chips are immersed in molten liquid tin and prepared. Tin is a metal that is less reactive than iron. It is neither oxidized by air nor reacts with water. Therefore, it is quite resistant to corrosion. A thin layer of tin is plated on the iron plate for good protection. However, if the plating is electrochemically corroded once it is destroyed, as iron is more active than tin, iron will degenerate as the anode of the primary cell and the presence of tin will accelerate the corrosion rate of iron. Therefore, tin and tin are different. In the case of a good coating, it has the function of protecting the iron.

Tinplate was first produced in Bohemia (now in the Czech Republic and Slovakia). The area has been rich in metal since ancient times, advanced technology, and know how to use water power in machine manufacturing, starting from the 14th century began production of tinplate. For a long period of time, it has been the main producer of tinplate in the world. At that time, tinplate was mainly used to make tableware and drinking equipment.

In the 17th century, Britain, France and Sweden had all hoped to establish their own tinplate industry. However, due to the large amount of funds required, it has not been developed. It was not until 1811 that Brian Tinkin and John Hall opened tin canned foods, but tinplate manufacturing began to develop on a large scale. Today, the world produces about 250,000 tons of tin each year, and more than one-third of it is used to make tinplate, most of which is used in the canned food industry.

2, tinplate hardness test

In the past, the hardness test of tinplate mostly used desktop surface Rockwell hardness tester, and the ordinary steel flat anvil was used to test the hardness of HR30T.

In recent years, since the national standard GB/T2520-2000 for tinplate has adopted the internationally accepted HR30Tm hardness expression method, the HR30Tm hardness value of diamond anvil and test tinplate has been adopted in China.

However, to test the HR30Tm hardness requires a diamond anvil, and the Rockwell hardness tester made in China rarely has such an accessory to purchase. Since the appropriate diamond anvil is difficult to buy, the desktop surface hardness tester is more expensive. Therefore, the application of the HR30Tm hardness representation method in the domestic tinplate industry is not yet common. Especially in the use of tinplate manufacturers, although people are also aware that the hardness of tinplate is very important, it must concern the quality of processed products, and it is related to the production efficiency and business benefits. However, most companies do not conduct hardness re-inspection on purchased tinplate materials.

Now, the situation is different. Shenyang Star Measurement & Control Instrument Co., Ltd. has produced a PHR series of portable Rockwell hardness tester. Its weight is only one percent of that of a desktop computer, and its price is only half that of a desktop computer. The accuracy is the same as that of a desktop computer. Meets the requirements of the national standard GB/T 230.1-2004 for Rockwell hardness test. As an option, Shenyang Tianxing can also provide diamond point anvils for testing HR30Tm hardness, which is only one-fifth the price of similar domestic products.

To test the hardness of tinplate, you can use PHR-1S surface rockwell hardness tester, which weighs only 0.7kg, you can test the thickness of the strip material is 0.05 ~ 25mm, test inner diameter of the pipe inner diameter of 26mm or more, test the inner diameter of 30mm or more Pipe outer wall hardness. With the diamond point anvil, the HR30Tm hardness of tinplate can be tested. This instrument can be easily brought to the production site, sales site and material warehouse to use. It can be used for on-line quality control of tinplate production plants. It can also be used for re-inspection of materials used in tinplate mills. It can also be used to purchase materials for the steel market. If equipped with an optional support base, it can also be placed on a platform (such as a desk) for precise testing.

The PHR-1S surface Rockwell hardness tester is very suitable for testing the hardness of tinplate. Its adoption will definitely bring obvious benefits to the production and use of tinplate manufacturers.