The secret of the attraction between stainless steel and magnet
Stainless steel iron with exquisite appearance, corrosion resistance, no deformation and other advantages, more and more by the majority of consumers. More and more stainless steel materials are used in daily necessities, urban buildings, etc., but people still don’t know enough about stainless steel materials. Some people grind stainless steel kitchenware with magnets when they buy stainless steel kitchenware. It is believed that what the magnet attracts is iron, but what it cannot attract is stainless steel.
Iron and steel are distinguished by their carbon content. The iron carbon alloy with carbon content less than 2% is steel, while the one with carbon content more than 2% is iron. Steel is widely used because of its toughness, elasticity and rigidity. What we come into contact with in our life is actually steel, but it’s called differently. Whether the magnet can hold or not, it is stainless steel as long as it meets the standard.
The corrosion resistant element of stainless steel is chromium. Steel containing more than 10.5% chromium will not rust. When smelting, the alloy elements added are different, so there is a talk between magnets that can be absorbed and magnets that cannot be absorbed. Stainless steel is generally divided into austenite, ferrite, martensite, etc. If different proportions of chromium and nickel are added to the molten steel, the austenitic steel produced is stainless steel which can not be absorbed by magnets; If chromium and a small amount of nickel are added to the molten steel, the steel is stainless steel that can be absorbed by magnets; The main alloying elements of martensitic stainless steel are chromium, iron and carbon. There are more than 100 kinds of stainless steel due to different alloy content. Except austenite, all stainless steels are magnetic.
Nickel has few reserves in the world and its price is very expensive. Therefore, the price of stainless steel with high nickel content is also higher in the market, and the magnet is not attractive. There is also a kind of stainless steel magnet that can’t be absorbed. That is the stainless steel with high manganese and little nickel or no nickel. The market price of this kind of stainless steel is 1000 yuan lower than that of stainless steel with high nickel content per ton. Some businesses will take advantage of people’s misunderstanding that “good stainless steel magnets can’t be absorbed” to mix goods and sell them as products of the same quality. There are more than 100 kinds of stainless steel with different characteristics and functions. Generally, austenitic stainless steel is used for decorative sculpture. Because of the low thermal conductivity of austenitic stainless steel, it is not suitable to use it as kettle and frying pan, which will waste energy and work time. Using ferritic stainless steel as frying pan and rice cooker not only has excellent corrosion resistance, but also its thermal conductivity is nearly half higher than that of austenitic stainless steel. Ferritic stainless steel should be used for washing machine inner barrel, water heater, vegetable washing basin, etc. as long as the utensils are in contact with water. Some people complain that stainless steel cutting tool is not fast, this is because the wrong choice of stainless steel. Austenitic stainless steel cannot be hardened and is not suitable for cutting tools.
Post time: Apr-26-2021