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Is the material of stainless steel screws magnetic?

There are many types of materials for making stainless steel screws, and they can be divided into several categories according to the structure at room temperature: austenitic type: such as 304, 321, 316, 310, etc.; martensite or ferrite type: such as 430, 420, 410 Wait;


 

Austenite is non-magnetic or weakly magnetic, while martensite or ferrite is magnetic. Due to component segregation or improper heat treatment during smelting, a small amount of martensite or ferrite in austenitic 304 stainless steel will result. In this way, 304 stainless steel will have weak magnetic properties.
    After 304 stainless steel is cold worked, the structure will also be transformed into martensite. The greater the degree of cold working deformation, the more martensite transformation and the greater the magnetic properties of the steel. Like a batch of steel belts, Φ76 tubes are produced without obvious magnetic induction, and Φ9.5 tubes are produced. Because the bending deformation is larger, the magnetic induction is more obvious, and the deformation of the square rectangular tube is larger than that of the round tube.
The stainless steel screws usually used as decorative tube plates are mostly austenitic 304 materials. Generally speaking, they are non-magnetic or weak magnetic. However, due to chemical composition fluctuations or different processing conditions caused by smelting, magnetism may also appear.
Hexagon head bolts and screws (thread diameter ≥ 5mm). Embossed or indented logo on the top of the head, or indented logo on the side of the head. Including performance level and factory standard. Carbon steel: The strength grade marking code is composed of two numbers separated by "•". The meaning of the number part before the "•" in the mark code indicates the nominal tensile strength, such as the "4" of the 4.8 grade indicates 1/100 of the nominal tensile strength of 400N/MM2. The meaning of "•" in the mark code and the number after the point indicates the yield strength ratio, that is, the ratio of the nominal yield point or the nominal yield strength to the nominal tensile strength. For example, the yield point of grade 4.8 products is 320 N/mm2. The strength grade mark of stainless steel products is composed of two parts separated by "—". The symbol before the "—" in the logo code indicates the material. Such as: A2, A4 and other signs "—" indicate strength, such as: A2-70 level.
Carbon steel: The mechanical performance levels of metric bolts can be divided into 10 performance levels: 3.6, 4.6, 4.8, 5.6, 5.8, 6.8, 8.8, 9.8, 10.9, and 12.9. Stainless steel is divided into three types: 60, 70, 80 (austenite); 50, 70, 80, 110 (martensite); 45, 60 (ferrite).

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