Grain size of a deliverable metal product can be improved by pre-setting recrystallization-suppressing dispersoids during casting. The outer regions of a direct chill cast embryonic ingot can undergo reheating before casting is complete. Through unique wiper placement and/or other reheating techniques, the temperature of the ingot can be permitted to reheat (e.g., up to approximately 410? C. to approximately 420? C.), allowing dispersoids to form. Stirring and/or agitation of the molten sump can facilitate formation of a deeper sump and desirably fine grain size as-cast. The formation of dispersoids during and/or immediately after casting can pin the grain boundaries at the desirably fine grain size, encouraging the same grain sizes even after a later recrystallization and/or solutionizing step.

Systems and associated methods are provided for controlling the shape of an ingot head during formation. At the end of a cast, prior to forming the ingot head, chill bars or other cooling structure may be lowered into an ingot mold and define a reduced casting footprint for forming the ingot head. Supplemental molten metal may be fed into the reduced casting footprint, and the chill bars may be moved laterally towards the center of the ingot, further reducing the casting footprint. As additional molten metal fills the reduced mold footprint, the ingot may be lowered relative to the chill bars to further increase the height of the ingot head. Additional molten metal may be added until the desired shape of the ingot head is formed.

Systems and associated methods are provided for controlling the shape of an ingot head during formation. At the end of a cast, prior to forming the ingot head, chill bars or other cooling structure may be lowered into an ingot mold and define a reduced casting footprint for forming the ingot head. Supplemental molten metal may be fed into the reduced casting footprint, and the chill bars may be moved laterally towards the center of the ingot, further reducing the casting footprint. As additional molten metal fills the reduced mold footprint, the ingot may be lowered relative to the chill bars to further increase the height of the ingot head. Additional molten metal may be added until the desired shape of the ingot head is formed.

A process for the sand casting of metals and their alloys includes the steps of providing at least a mold equipped with a plurality of cooling nozzles, making a layer of coolant permeable materials covering the nozzles and maintaining the materials at desired temperatures, delivering a molten metal into the mold, supplying predetermined amount of coolant to each nozzles to contact the external surface of the casting at desired rate, time, and duration to achieve an acceptable level of progressive solidification from the distal end of the casting towards the riser until the casting has reached desired temperatures.

A process for the sand casting of metals and their alloys includes the steps of providing at least a mold equipped with a plurality of cooling nozzles, making a layer of coolant permeable materials covering the nozzles and maintaining the materials at desired temperatures, delivering a molten metal into the mold, supplying predetermined amount of coolant to each nozzles to contact the external surface of the casting at desired rate, time, and duration to achieve an acceptable level of progressive solidification from the distal end of the casting towards the riser until the casting has reached desired temperatures.

The present invention belongs to the field of metal processing and fabrication, and particularly relates to an apparatus for high-throughput screw caster of a multi-component gradient metal material from elongate materials, such as multi-component alloy pipes, rods, profiles, and other such materials, having in the lengthwise direction a continuous gradient distribution of chemical components. The apparatus includes an online powder flow-rate regulation system, a rotary feed system, a heating system, a heat insulation system, a motor drive system, a blank forming system and a control system. Due to the adoption of the above technical solution, the apparatus of the present invention is simple in structure, and easy to use and control.

The present invention belongs to the field of metal processing and fabrication, and particularly relates to an apparatus for high-throughput screw caster of a multi-component gradient metal material from elongate materials, such as multi-component alloy pipes, rods, profiles, and other such materials, having in the lengthwise direction a continuous gradient distribution of chemical components. The apparatus includes an online powder flow-rate regulation system, a rotary feed system, a heating system, a heat insulation system, a motor drive system, a blank forming system and a control system. Due to the adoption of the above technical solution, the apparatus of the present invention is simple in structure, and easy to use and control.

Provided is a spray nozzle configured so that the angle of spray does not change even if the flow rate of liquid is adjusted largely. A circular conical primary hole narrowing toward the discharge-side front end is provided in a communicating manner at the discharge-side center of a primary flow passage extending along the center axis of a nozzle body, and a pair of secondary holes is provided on both sides of the primary hole in the width direction so as to communicate with the primary flow passage and the primary hole. The secondary holes are formed in an elongated shape, and portions of the long sides of the secondary holes on both sides, the portions facing each other across the primary hole, and both side portions of the primary hole are connected.

A high strength steel sheet having excellent surface quality and formability with a tensile strength of 980 MPa or more and a TS-El balance of 30000 MPa % or more is provided. A high strength steel sheet comprises: a chemical composition containing C: 0.08% to 0.30%, Si: 2.0% or less, Mn: more than 3.0% and 10.0% or less, P: 0.05% or less, S: 0.01% or less, Al: 1.5% or less, Ti: 0.010% to 0.300%, and N: 0.0020% to 0.0100% in a range satisfying 1.1(Ti+Mn.sup.1/2/400)/(0.01+5N)6.0; and a microstructure including a retained austenite phase and a ferrite phase, wherein a ratio Mn/Mn of an average Mn concentration (Mn) of the retained austenite phase to an average Mn concentration (Mn) of the ferrite phase is 1.5 or more.

A process that produces a microalloyed steel in an integrated casting-rolling plant having a continuous casting machine with a mold, a single- or multi-stand prerolling train, a finish-rolling train having a first stand group with at least one first finish-rolling stand and a second stand group having at least one stand cooler. A metallic melt is cast in the mold to obtain a partly solidified thin-slab strand, which is supported, deflected and cooled. The solidified thin-slab strand is rolled by the prerolling train to obtain a prerolled strip that is finish-rolled in the first stand group to obtain the finish-rolled strip, which is fed to the second stand group and force-cooled in the second stand group, the finish-rolled strip having a thickness that results in a cooling rate of the core of the finish-rolled strip in the second stand group greater than 20? C./s and less than 200? C./s.