Provided are: a high-strength cold-rolled steel sheet for which little load is required during cold working and which has superior formability and ductility such that certain conditions are satisfied with regard to the evaluation of formability and retained austenite; a hot-rolled steel sheet which serves as the material of the high-strength cold-rolled steel sheet; and manufacturing methods for the high-strength cold-rolled steel sheet and the hot-rolled steel sheet, each of the manufacturing methods including a first step for subjecting a rolling material to rough rolling with a total rolling reduction of 30% or greater, a second step for subjecting the rolling material to finish rolling with a total rolling reduction of 40% or greater using a plurality of different diameter rolls having diameters that differ from one another in a temperature environment of 800ºC or greater, and a third step for winding the rolled product in a temperature environment of 700ºC or greater.
C21D 9/46 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articlesFurnaces therefor for sheet metals
B21B 1/22 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-sectionSequence of operations in milling trainsLayout of rolling-mill plant, e.g. grouping of standsSuccession of passes or of sectional pass alternations for rolling bands or sheets of indefinite length
B21B 1/26 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-sectionSequence of operations in milling trainsLayout of rolling-mill plant, e.g. grouping of standsSuccession of passes or of sectional pass alternations for rolling bands or sheets of indefinite length in a continuous process by hot-rolling
B21B 3/00 - Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences
Provided is a fully-fledged industrial-use material amorphous alloy with a wide range of applications, that solves the issues of delayed fractures and ductility, etc., and that includes: 63 at% or more Ni; 10%-25 at% B, as a semimetal for amorphization; and one or more of Cr, Mo, or Nb for the remainder.
A device for forming an amorphous coating film is disclosed in which a flame containing raw-material particles is jetted from a spray gun toward a base material to melt the raw-material particles by the action of the flame, and the raw-material particles and the flame are cooled with a cooling gas before reaching the base material. In the device, a cylindrical structure which separates the flame from the outside air have been disposed in the region for melting the raw-material particles which is part of the passage through which the flame from the spray gun is jetted, and a channel for the cooling gas has been formed so that the channel is integrated with the cylindrical structure. This device has advantages that it is possible to form amorphous coating films of various metals including a metal that has a high melting point and a narrow supercooled-state temperature range and that the device is compact and generates little oxide.
B05B 7/20 - Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas incorporating means for heating the material to be sprayed by flame or combustion
C23C 4/12 - Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
4.
PROCESS FOR PRODUCTION OF COLD-ROLLED STEEL SHEET HAVING EXCELLENT PRESS MOLDABILITY, AND COLD-ROLLED STEEL SHEET
Disclosed are: a cold-rolled steel sheet which undergoes less load during cold rolling and has excellent press moldability and high strength; and a process for producing the cold-rolled steel sheet. A hot-rolled steel sheet comprising 0.10 to 0.30 mass% of C, 0.2 mass% or more of Mn, 0.01 mass% or more of Ni (wherein the sum total of Mn and Ni is 0.5 to 2.5 mass%), and 1.2 to 9.0 mass% of Cr, with the remainder being iron and unavoidable impurities, and having a tensile strength of 1000 MPa or less is washed with an acid, and is subjected to cold rolling at a total rolling ratio of 60% or more, thereby producing a cold-rolled steel sheet. The cold-rolled steel sheet is subjected to the final continuous annealing treatment at a homogenizing temperature of 750˚C or higher and a cooling rate of 3 to 100˚C/s. In this manner, a cold-rolled steel sheet having a tensile strength of 1280 MPa or more, a breaking elongation of 3% or more, and a thickness of 0.05 to 0.60 mm.
A method and apparatus for forming an ordinary amorphous coating film not limited to metallic glasses, etc. by thermal spraying. A flame (F) containing material particles is ejected from a nozzle (5) toward a base material (M). The material particles are melted by the flame (F), and these material particles and the flame (F) begin to be cooled before they reach the base material (M). For the cooling, a gas (H) is blown from outer peripheral areas apart from the flame (F) so that the gas (H) approaches the center line for the flame (F). It is preferable that the material particles in the flame (F) have a particle diameter of 10-100 쎽m.
C23C 4/12 - Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
B05B 7/20 - Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas incorporating means for heating the material to be sprayed by flame or combustion
patents
