Magnet why can not suck stainless steel magnet manufacturer people often with magnet adsorption stainless steel material, verify the quality of true and false.
Don't absorb non-magnetic, think is good, on the other hand, is considered a fake fake.
Actually, this is a kind of unrealistic about it.
Recently, operating stainless steel window has more than 10 years of Mr Li told reporters, depend on whether the traditional magnetic to discriminant method of stainless steel, is likely to suffer.
According to his introduction, there are many different kinds of stainless steel and normal temperature can be divided into austenite size according to the organization structure and martensite or iron grain size.
Austenite size is non-magnetic or weak magnetic, martensite or iron grain size are magnetic.
However, is not necessarily so.
Such as usually used for decoration of austenite tube plate material 304, generally speaking is no magnetic, but caused by smelting chemical composition may also appear different magnetic fluctuations or processing status, it cannot be considered a counterfeit or substandard.
Another 304 stainless steel after cold working, the organization structure to martensite transformation, the greater the degree of cold deformation, martensitic transformation, the more the greater the magnetic steel.
On the contrary, a little quality time of 200 series stainless steel, is likely not magnetic, thus determine it is real stainless steel, would be a mistake.
Stainless steel is a great invention in the history of metallurgy in the 20th century, he is on the basis of the carbon steel to add a certain content of chromium elements made of smelting.
Stainless steel is not rust resistance, the key is because of containing chromium in steel.
The required minimum chromium content in the United States, the European standard for not less than 10.
After mass fraction, with)
, Japanese industrial standard provision is generally not less than about 11%, China's general think not less than 12%.
Because of the influence of chromium in corrosive medium, under the action of the generated on the surface of the steel a strong dense layer of oxide film, called & other;
Passivation membrane & throughout;
The membrane to make metal dielectric isolation with the outside world, prevent the metal from being further corrosion;
And also have the ability to repair itself, if once destroyed, the chromium in steel can with the oxygen in medium to regenerate the passivation membrane, continue to protection.
Stainless steel stainless sex, but also related to use of the environment, different environment, to use the chromium content in different stainless steel.
The discretion of the chromium content is the fundamental factors to stainless steel performance.
So no chrome, no stainless steel and ordinary carbon steel and stainless steel containing chromium are a magnet material.
Stainless steel is divided into five categories: austenitic stainless steel and ferritic stainless steel, martensite stainless steel, austenitic & ndash;
Ferrite duplex stainless steel and precipitation hardening stainless steel.
Only one part of austenitic stainless steel and precipitation hardening stainless steel (
Austenitic precipitation-hardening stainless steel)
Is no magnetic, can't use magnet to absorb;
He and the types of stainless steel are the magnet, can use a magnet to absorb.
In weak corrosive medium, such as air, water, steam and not rusty steel is stainless steel, the strong corrosive medium such as acid, alkali, salt solution in the corrosion of the steel is corrosion resistant steel, stainless steel not corrosion resistant, corrosion resistant must be stainless steel.