Patent application number | Description | Published |
20090238715 | STEEL SHEET FOR HOT PRESS FORMING HAVING LOW-TEMPERATURE HEAT TREATMENT PROPERTY, METHOD OF MANUFACTURING THE SAME, METHOD OF MANUFACTURING PARTS USING THE SAME, AND PARTS MANUFACTURED BY THE SAME - A steel sheet for forming having low-temperature heat treatment property, in which heat treatment is performed within a range of lower temperature than a conventional steel sheet in the event of hot press forming or post-heat treatment after cold forming, a method of manufacturing the same, and a method of manufacturing parts using the same. The steel sheet has a composition of, by weight, carbon (C): 0.15 to 0.35%, silicon (Si): 0.5% or less, manganese (Mn): 1.5 to 2.2%, phosphorus (P): 0.025% or less, sulfur (S): 0.01% or less, aluminum (Al): 0.01 to 0.05%, nitrogen (N): 50 to 200 ppm, titanium (Ti): 0.005 to 0.05%, tungsten (W): 0.005 to 0.1%, and boron (B): 1 to 50 ppm, wherein Ti/N: less than 3.4, where Ti/N is the atomic ratio of the corresponding elements, Ceq expressed by the following formula ranges from 0.48 to 0.58, and temperature Ar3 ranges from 670° C. to 725° C. Wherein Ceq=C+Si/24+Mn/6+Ni/40+Cr/5+V/14 where C, Si, Mn, Ni, Cr and V indicate the contents (wt %) of the respective elements. | 09-24-2009 |
20110300407 | Aluminum-Plated Steel Sheet Having Superior Corrosion Resistance, Hot Press Formed Product Using the Same, and Method for Production Thereof - Provided are a coated steel sheet, a hot press formed product using the steel sheet, and a producing method thereof. Conditions for hot-dip coating bath are optimized when an aluminum-coated steel sheet is produced using a hot rolled steel sheet or a cold rolled steel sheet, and processes are controlled during production of a hot press formed product from the steel sheet, thereby forming a coating layer having a high ratio of (Fe | 12-08-2011 |
20120267012 | ZINC-PLATED STEEL SHEET FOR HOT PRESSING HAVING OUTSTANDING SURFACE CHARACTERISTICS, HOT-PRESSED MOULDED PARTS OBTAINED USING THE SAME, AND A PRODUCTION METHOD FOR THE SAME - Provided is a zinc-plated steel sheet for hot pressing having outstanding surface characteristics, comprising: a steel foundation plate comprising a metal surface diffusion layer of which the Gibbs free energy reduction per mole of oxygen during oxidation is less than that of Cr; an aluminum-rich layer containing at least 30 wt. % of aluminium formed on the surface diffusion layer, and a zinc plating layer formed on the aluminum-rich layer. In this way, a metal having a low affinity for oxygen is coated to an effective thickness prior to annealing and thus the creation of annealing oxides at the surface of the steel sheet is suppressed and a uniform zinc plating layer is formed, and alloying of the zinc plating layer is promoted during press-processing heat treatment. Cracking in the steel foundation plate during hot press molding is prevented. | 10-25-2012 |
20120291510 | HOT PRESS FORMING PROCESS OF PLATED STEEL AND HOT PRESS FORMED ARTICLES USING THE SAME - Disclosed are a hot press forming method and a product formed using the hot press forming method, able to process a plated steel blank under appropriate heat treatment conditions to prevent the volatilization of a plated layer and the formation of oxidized scale, and which divisionally heats the plated steel blank in a secondary heating process to provide different strengths and physical properties to the product. The hot press forming method includes primarily and entirely heating the plated steel material to a predetermined temperature and maintaining the plated steel material at the predetermined temperature, secondarily and rapidly heating at least one portion of the plated steel material after the high temperature maintenance of the plated steel material, and performing a hot press forming and cooling process on the secondarily heated plated steel material. | 11-22-2012 |
Patent application number | Description | Published |
20130295402 | Steel Sheet for Formed Member Having Enhanced Ductility, Formed Member, and Method for Manufacturing the Formed Member - Provided is a steel sheet for a formed member having enhanced ductility, a formed member, and a method for manufacturing the formed member, and more particularly, to a steel sheet for making a formed member having high strength and ductility such as an automotive structural member and a reinforcing member, a formed member, and a method for manufacturing the formed member. The steel sheet for a formed member has enhanced ductility, and includes, by weight %, C: 0.1% to 1.0%, Si+Al: 0.4% to 3.0%, Mn: 0.1% to 5.0%, P: 0.0001% to 0.1%, S: 0.0001% to 0.03%, N: 0.03% or less (but not 0%), and the balance of Fe and inevitable impurities. The formed member having high strength and ductility that can be used for forming an automotive structural member, a reinforcing member, etc. In addition, the formed member can be used for a heat-treatable impact resistant member. | 11-07-2013 |