Menetelmä metallipinnoitetun ja kuumamuokatun teräskomponentin valmistamiseksi ja metallipinnoitettu teräsnauhatuote

摘要

The present invention relates to a method for manufacturing a metal coated and hot-formed steel component by direct hot-forming techniques and to a metal coated steel strip product for direct hot-forming. Improvements in mechanical properties of the metal coated and hot-formed steel component are difficult to be obtained without weakening the weldability. According to the invention, the grain structure of a metal coated steel strip made of hardenable steel alloy is deformed comprising non-recrystallized grains and a yield ratio (YS/TS) of said steel strip is higher than 0.75. Recrystallization of said grain structure is at least retarded or even totally avoided or leaved out prior to and during applying metal coating on the surface of the steel strip. This kind of material cannot be used in indirect press hardening, but fits excellently to direct hot press forming and provides possibility to affect mechanical properties without weakening weldability.