Views: 208 Author: Site Editor Publish Time: 2021-05-25 Origin: Site
The "stainlessness" of stainless steel is not absolutely non-rusting, but it is relatively non-rusting under certain conditions. If the user uses it improperly or in an environment that exceeds its corrosion resistance, stainless steel products will rust.
With the improvement of safety awareness, when people buy stainless steel kitchenware and wine utensils, they will choose food-grade stainless steel to protect their safety and health. The stainless steel products commonly used in our lives mainly include stainless steel water bottle, stainless steel insulated tumbler and stainless lunch box.
Many people still don't know much about food grade stainless steel. What types of food-grade stainless steel are there? What are the differences between food-grade stainless steel and 304 stainless steel? Below we will reveal how to easily identify stainless steel.
As we all know, 304 stainless steel products are food grade, which is healthy and harmless to humans. Consumers usually prefer 304 stainless steel wine and cooking utensils. However, how to determine that the stainless steel purchased is made of 304 stainless steel?
The well-known 304 steel is austenitic stainless steel. The extensive use of stainless steel products is a revolution in the kitchen, directly changing the color and touch of the kitchen.
1. Magnetic detection. Stainless steel is divided into austenitic stainless steel and ferritic stainless steel. Among them, austenitic stainless steel is non-magnetic, while ferritic stainless steel is a strong magnetic steel body. A series of experiments have proved that austenitic stainless steel has insignificant magnetism under certain special conditions, but it is non-magnetic under normal conditions. Although the magnet can basically distinguish between chromium stainless steel and chromium nickel stainless steel, it cannot correctly distinguish certain steel grades for special purposes and cannot distinguish specific steel grades.
This method can be used to distinguish the stainless steel thermo lunch box and the stainless bento box.
2. Identify with copper sulfate. Remove the oxide layer on the steel, drip a drop of water, and rub it with copper sulfate. The color does not change after rubbing, so it is usually stainless steel. The color changes to purple after rubbing, the non-magnetic steel is high manganese steel, and the magnetic steel is usually ordinary steel or low alloy steel.
3. Identification of color. The pickled stainless steel has a silvery white and smooth surface. The color of chromium-nickel stainless steel is silver and jade. The color of chrome stainless steel is white and slightly gray and weak in luster. The color of chromium-manganese-nitrogen stainless steel is slightly lighter than that of chromium-nickel stainless steel. The surface color of unpickled stainless steel. Chrome-nickel steel is brown-white, chrome steel is brown-black, and chromium-manganese-nitrogen is black (the three colors refer to the more oxidized colors). The surface of cold-rolled, unannealed chromium-nickel stainless steel is silver-white and reflective.
In this way you can roughly check the stainless steel coffee cup, stainless steel camping mug and kid stainless steel bento box.
For products with untrustworthy sources, the most reliable method is to send them to the laboratory. But most consumers do not have this condition. The above methods allow us to reasonably identify single wall stainless steel water bottle and stainless steel wine tumbler to a certain extent.