Higher-strength steels

Description

Micro-alloyed steels
Micro-alloyed steels have been in use for a considerable time. They combine relatively good formability with high tensile strength. Designation: ZStE 260, ZStE 300, ZStE 340, ZStE 380, ZStE 420.
The number listed in the designation of the steel for steels ending in ""E"" represents the tensile yield strength of the material in N/mm² (1 N/mm² = 142 psi). For ultra-high-strength steels on the other hand the tensile strength is often given. The clearest designation includes both values, for example ZstE 340/410.

Phosphorus-alloyed steels
Phosphorus-alloyed steels are similar to micro-alloyed steels.  In this case, the alloyed element, phosphorus, increases the strength. Designation: ZStE 220 P, ZStE 260 P, ZStE 300 P

Isotropic steels
These are improved micro-alloyed steels that demonstrate no dependence of the material values on the rolling direction (no "earing").