| 摘要 |
The invention relates to a process for making a hot stamped coated steel sheet product, comprising the steps of pre-coating a steel strip or sheet with aluminium-or aluminium alloy, cutting said pre-coated steel strip or sheet to obtain a pre-coated steel blank, heating the blank in a furnace preheated to a temperature and during a time defined by diagram according to thickness, at a heating rate Vc between 20 and 700° C. comprised between 4 and 12° C./s and at a heating rate Vc′ between 500 and 700° C. comprised between 1.5 and 6° C./s, to obtain a heated blank; then transferring said heated blank to a die, hot stamping the heated blank in the die obtain a hot stamped steel sheet product, cooling at a mean rate Vr between the exit of the heated blank from the furnace, down to 400° C., of at least 30° C./s.
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