Abstract: The invention concerns a method for making hardenable steel plates by firing comprising: preparing a steel whereof the composition comprises, expressed in weight percent: 0.03=C=0.06, 0.50=Mn=1.10, 0.08:=Si=0.20, 0.015=Al=0.070, N=0.007, Ni=0.040, Cu=0.040, P=0.035, S=0.015, Mo=0.010, Ti=0.005; provided that it comprises boron in an amount such that 0.64=B/N=1.60 the rest consisting of iron and impurities resulting from production; casting a slab of said steel, then hot rolling of said slab to obtain a plate, the final rolling temperature being higher than the point Ar3; winding said plate at a temperature ranging between 500 and 700° C.; then cold rolling of said plate at a reduction rate ranging between 50 and 80%; continuous annealing heat treatment for a time interval less than 15 minutes; and strain hardening with a reduction rate ranging between 1.25 and 2.5%. The invention also concerns the hardenable plates and the parts obtainable therefrom.

Abstract: A steel having a composition, expressed in wt. %, of: 0.03?C?0.06; 0.50?Mn?1.10; 0.08?Si?0.20; 0.015?Al?0.070; N?0.007; Ni?0.040; Cu?0.040; P?0.035; S?0.015; Mo?0.008; Ti?0.005; and boron in an amount such that: 0.65?B/N?1.60, the rest of the composition consisting of iron and impurities resulting from preparation. Also a method for making steel plates having this composition, and the resulting plates, produced by the method.

Abstract: The invention concerns a method for making hardenable steel plates by firing comprising: preparing a steel whereof the composition comprises, expressed in weight percent: 0.03=C=0.06, 0.50=Mn=1.10, 0.08:=Si=0.20, 0.015=Al=0.070, N=0.007, Ni=0.040, Cu=0.040, P=0.035, S=0.015, Mo=0.010, Ti=0.005; provided that it comprises boron in an amount such that 0.64=B/N=1.60 the rest consisting of iron and impurities resulting from production; casting a slab of said steel, then hot rolling of said slab to obtain a plate, the final rolling temperature being higher than the point Ar3; winding said plate at a temperature ranging between 500 and 700° C.; then cold rolling of said plate at a reduction rate ranging between 50 and 80%; continuous annealing heat treatment for a time interval less than 15 minutes; and strain hardening with a reduction rate ranging between 1.25 and 2.5%. The invention also concerns the hardenable plates and the parts obtainable therefrom.

Abstract: The invention concerns a steel whereof the composition, expressed in wt. %, comprises: 0.03≦C<0.06; 0.50≦Mn≦1.10; 0.08≦Si≦0.20; 0.015≦Al≦0.070; N≦0.007; Ni≦0.040; Cu≦0.040; P≦0.035; S≦0.015; Mo≦0.008; Ti≦0.005; providing that it also comprises boron in an amount such that: 0.65≦B/N≦1.60, the rest of the composition consisting of iron and impurities resulting from preparation. The invention also concerns a method for making steel plates having said composition and the resulting plates.

Abstract: An electrogalvanizing process, in which a strip is moved past an anode, plating solution is made to flow at a speed V with respect to the moving strip, and an electric current of current density J greater than 50 A/dm.sup.2 is passed between the strip and the anode, which comprises carrying out the deposition under conditions such that:J/J.sub.lim is less than or equal to 0.15;J.sup.2 /J.sub.lim is less than or equal to 22 A/dm.sup.2 ;where J.sub.lim is the limiting current density, corresponding to the current density plateau in the current versus potential curve characteristic of the plating solution flowing at the speed V in the vicinity of the strip. An electroplating cell of the radial type for implementing the process, in which cell the anode bed is continuous, is disclosed. The process facilitates the high-speed deposition of zinc which has low rugosity and is free of edge dendrites.