（1） Yield strength
The yield strength is small and the material is easy to deform. When compressed, it is not easy to wrinkle. For bending deformation, it will have little elasticity, that is, good moldability and setting.
（2） Yield ratio
The smaller the yield ratio is, the material is easy to plastic deformation and not easy to crack.
（3） Elongation
Elongation represents the sheet metal's ability to produce uniform deformation or stable plasticity, which directly determines the stamping forming ability in elongation deformation. Elongation is the most important parameter affecting the forming performance of hole turning or reaming.
（4） Strain hardening index n
The higher the value of N, the higher the strength of the high deformation zone in the forming process of steel, and the deformation is easy to spread to the near low deformation zone, so that the strain distribution is more uniform and the phenomenon of local deformation concentration is reduced. The value of n is particularly important for stretch bulging.
（5） Plastic strain ratio R value
Due to the different properties of cold rolled steel sheet, R value represents the strain ratio in width direction and thickness direction when the steel sheet is stretched. The larger R, the less likely the material is to develop deformation in the thickness direction, and the better the deep drawing performance.
In addition to the above main mechanical properties, common ones are cupping value (ie) and bake hardening value (BH). Cup protrusion value is used to evaluate the stretch bulging energy of sheet metal. The larger the cup protrusion value, the better the stretch bulging energy. Bake hardening value refers to the increase of yield strength when the sample is maintained at 170 temperature for 20 minutes after deep drawing. It is one of the main properties of bake hardening steel.
（6） Deep drawing steel plate, also known as deep drawing ordinary strength cold rolled steel, includes ST12, ST13 and ST14 (st1405, st14f and st14hf).
ST12, also known as aluminum killed steel, has certain strength and good plasticity. It is used for general forming processing of automobile water tank shell.
ST13 and ST14 are also called special killed steel, i.e. non aging steel. Compared with ST12, this steel has no slip line on the part surface after stamping, that is, the surface quality of stamping parts is better. ST13 is commonly used in stamping forming of automobile doors and windows. ST14 is commonly used for deep stamping forming such as automobile fuel tank. 05 in st1405 indicates that the surface quality of steel is good and there are no scratches and other defects, while ST14 (F / HF), f indicates complex drawing level and HF indicates very complex drawing level.
（7） High strength steel plate, also known as deep drawing phosphorus containing high strength ultra-low carbon killed steel, including B170P1 and b210p1.
Due to the addition of phosphorus in the steel plate, phosphorus has a strong strengthening ability, about 7 times that of silicon and 10 times that of manganese. Therefore, in order to obtain the same strength, only a small amount of phosphorus needs to be added, and the reduction of plasticity and elongation due to the addition of a large amount of silicon and manganese can be avoided. On the other hand, the carbon content in the steel is very low, which improves the plasticity and elongation of the steel. Therefore, this kind of steel has good stamping properties, high strength and bake hardening properties.
（8） Ultra deep drawing steel plate, also known as ultra deep drawing high strength and ultra-low carbon if steel, refers to ST16 and st1605.
The steel is also called interstitial free steel because strong carbon and nitriding living substances are added to fix the carbon and nitrogen atoms in the steel. The steel has very good stamping properties and good bake hardening properties.
（9） Bake hardening plate, also known as ultra-low carbon bake hardening steel, refers to b140h1 and b180h1.
When the steel is cold rolled and annealed, the carbon and nitrogen atoms exist in interstitial solid solution. When the high-temperature aging treatment after pre deformation, the carbon and nitrogen atoms gather and nail to the dislocation, which improves the yield strength of the material. Therefore, this kind of steel has good bake hardening properties. The steel plate has low yield strength before stamping. After deep drawing deformation or stamping forming and painting and baking, the yield strength is improved to a certain extent, that is, the concave resistance is improved.
（10） Pickled steel plate, including SPHC, sphe and saph370.
This kind of steel has the advantages of short production process, low cost, high strength and good elongation. It is used to manufacture automobile frames, wheels and other parts.
