HIGH-STRENGTH MULTI-PHASE STEEL FOR COLD OR HOT-STEEL STRIP AND METHOD FOR MAKING COLD-AND HOT-STEEL STRIP

摘要

1. High-strength multiphase steel for cold or hot rolled steel strip with excellent molding properties, in particular for automotive industry based on lightweight structures, consisting of elements, wt.%: C - 0,060 to ≤0,115Al - 0,020 to ≤0,060Si - 0,100 to ≤0,500Mn - 1,300 to ≤2,500P - ≤0,025S - ≤0,0100Cr - 0,280 to ≤0,480Mo - ≤0,150Ti - ≥0,005 to ≤0,050Nb - ≥0,005 to ≤0,050B - ≥0,0005 to ≤0 , 0060N - ≤0.0100 iron - the rest, including ordinary associated steels, elements not mentioned above. 2. Steel according to claim 1, characterized in that the Mo content is ≤0.100%. Steel according to claim 1 or 2, characterized in that the Mo content is ≥0.050% .4. Steel according to claim 1, characterized in that the Nb content is ≤0.045% .5. Steel according to claim 1, characterized in that the Nb content is ≤0.040% .6. Steel according to claim 1, characterized in that the Ti content is ≤0.045%. Steel according to claim 1, characterized in that the Ti content is ≤0.040% .8. Steel according to claim 1, characterized in that the content of B is ≤0.0050% .9. Steel according to claim 1, characterized in that the content of B is ≤0.0040% .10. Steel according to claim 1, characterized in that the N content is ≤0.0090% .11. Steel according to claim 1, characterized in that the N content is ≤0.0070% .12. Steel according to claim 1, characterized in that the total content of Ti, Nb and B is ≤0.0106% .13. Steel according to claim 1, characterized in that the total content of Ti, Nb, B and Mo is ≤0.0256%. A method of manufacturing a cold or hot rolled steel strip from steel made according to any one of claims 1 to 13, wherein the necessary multiphase structure is created during continuous annealing, characterized in that the cold or hot rolled steel strip in a continuous annealing furnace is heated to a temperature of range from 700 to 9500 ° C and annealed steel strip