Disclosed is a duplex stainless clad steel plate in which a duplex stainless steel plate as a cladding metal is bonded or joined to one or both surfaces of a base steel plate, in which the base steel plate comprises a predetermined chemical composition such that Nb/N is 3.0 or more and Ceq is 0.35 to 0.45, and the duplex stainless steel plate comprises: a predetermined chemical composition such that PI is 34.0 to 43.0; and a microstructure containing a ferrite phase in an area fraction of 35% to 65%, and in the microstructure, an amount of precipitated Cr is 2.00% or less and an amount of precipitated Mo is 0.50% or less.

Process for rolling aluminum foils includes: providing first and second laminates each having two aluminum foils overlapped one to another between which a lubricant is interposed; lubricating one face of one laminate between the first and second laminate; coupling the first laminate with the second laminate obtaining a double laminate. The lubricated face is a contact face between the first and second laminate; or it is a non-contact face between the first and second laminate, in this case being provided the intermediate steps of winding the double laminate obtaining a wound double laminate having n coils; partially separating the wound double laminate by unwinding, by one coil, both the aluminum foils of one of the first and second laminate, obtaining an at least partially wound double laminate having an end portion constituted by a respective portion of both the aluminum foils of only one of the first and second laminate.

Process for rolling aluminum foils includes: providing first and second laminates each having two aluminum foils overlapped one to another between which a lubricant is interposed; lubricating one face of one laminate between the first and second laminate; coupling the first laminate with the second laminate obtaining a double laminate. The lubricated face is a contact face between the first and second laminate; or it is a non-contact face between the first and second laminate, in this case being provided the intermediate steps of winding the double laminate obtaining a wound double laminate having n coils; partially separating the wound double laminate by unwinding, by one coil, both the aluminum foils of one of the first and second laminate, obtaining an at least partially wound double laminate having an end portion constituted by a respective portion of both the aluminum foils of only one of the first and second laminate.

A dual-hardness clad steel plate. One surface of the steel plate is a high-hardness layer, the other surface of the steel plate is a low-hardness layer, and a combination of atoms is achieved between the high-hardness layer and the low-hardness layer by rolling bonding, wherein Mn13 steel is adopted for the low-hardness layer, and the Brinell hardness of the high-hardness layer is greater than 600. Further disclosed is a production method of the dual-hardness clad steel plate, comprising: 1) respectively preparing a high-hardness layer slab and a low-hardness layer slab; 2) assembling: preprocessing combined faces of the slabs, carrying out peripheral welded sealing on joint faces of the slabs, and carrying out vacuumizing treatment on a composite slab after welded sealing; 3) heating; 4) carrying out composite rolling; 5) cooling; and 6) carrying out thermal treatment, wherein the heating temperature is 1050-1100 C., the heating time is 2-3 min/mmslab thickness, and water cooling is performed on the heated slab, and the water temperature is lower than 40 C. The steel plate has different hardness characteristics and good low-temperature toughness.

A dual-hardness clad steel plate. One surface of the steel plate is a high-hardness layer, the other surface of the steel plate is a low-hardness layer, and a combination of atoms is achieved between the high-hardness layer and the low-hardness layer by rolling bonding, wherein Mn13 steel is adopted for the low-hardness layer, and the Brinell hardness of the high-hardness layer is greater than 600. Further disclosed is a production method of the dual-hardness clad steel plate, comprising: 1) respectively preparing a high-hardness layer slab and a low-hardness layer slab; 2) assembling: preprocessing combined faces of the slabs, carrying out peripheral welded sealing on joint faces of the slabs, and carrying out vacuumizing treatment on a composite slab after welded sealing; 3) heating; 4) carrying out composite rolling; 5) cooling; and 6) carrying out thermal treatment, wherein the heating temperature is 1050-1100 C., the heating time is 2-3 min/mmslab thickness, and water cooling is performed on the heated slab, and the water temperature is lower than 40 C. The steel plate has different hardness characteristics and good low-temperature toughness.

The ratio of the difference between a surface distance L at each of the different positions in a width direction DW of a metal sheet and a minimum surface distance Lm to the minimum surface distance Lm is an elongation difference ratio. The elongation difference ratio in a center section in the width direction DW of the metal sheet is less than or equal to 310.sup.5. The elongation difference ratios in two edge sections in the width direction DW of the metal sheet are less than or equal to 1510.sup.5. The elongation difference ratio in at least one of the two edge sections in the width direction DW of the metal sheet is less than the elongation difference ratio in the center section in the width direction of the metal sheet.

The ratio of the difference between a surface distance L at each of the different positions in a width direction DW of a metal sheet and a minimum surface distance Lm to the minimum surface distance Lm is an elongation difference ratio. The elongation difference ratio in a center section in the width direction DW of the metal sheet is less than or equal to 310.sup.5. The elongation difference ratios in two edge sections in the width direction DW of the metal sheet are less than or equal to 1510.sup.5. The elongation difference ratio in at least one of the two edge sections in the width direction DW of the metal sheet is less than the elongation difference ratio in the center section in the width direction of the metal sheet.

A method for forming a multilayer composite structure comprises providing a first sheet comprising a copper-comprising layer sandwiched by first and second graphene layers, wrapping the first sheet to form a first rod, and compacting the first rod to form a first multilayer composite structure.

An interlockable structural panel with a channel cross-section including a base and first and second side wall forming the sides of the channel, wherein an end of the first side wall distal the base is curved as a first arc directed away from a central portion of the channel and an end of the second side wall is curved as a second arc directed towards the central portion of the channel and wherein a straight section extends from the end of the second arc distal the base. Also methods for forming interlockable structural panels and for forming curved interlockable structural panels for constructions including roofs.

An interlockable structural panel with a channel cross-section including a base and first and second side wall forming the sides of the channel, wherein an end of the first side wall distal the base is curved as a first arc directed away from a central portion of the channel and an end of the second side wall is curved as a second arc directed towards the central portion of the channel and wherein a straight section extends from the end of the second arc distal the base. Also methods for forming interlockable structural panels and for forming curved interlockable structural panels for constructions including roofs.