| Patent application number | Description | Published |
|---|
| 20080210351 | Formed product and method for production thereof - A formed product, characterized in that it is produced by using, as a material, a steel having an ultra fine structure comprising ferrite grains having an average grain diameter of 3 μm or less and by a method comprising only a forming step and including none of refining steps; and a method for producting the above formed product with ease. The formed product contains no alloying element and has been subjected to no refining step, and has been imparted with high strength and high toughness by the above ultra fine structure. | 09-04-2008 |
| 20090185943 | STEEL PLATE AND STEEL PLATE COIL - In a steel plate having tensile strength of 1 GPa or more at the normal temperature, the steel plate is made, stress decrement (SD) after uniform elongation in the stress-strain diagram obtained by using a tabular specimen of which is not less than 1.8×10 | 07-23-2009 |
| 20090236015 | ULTRAHIGH STRENGTH STEEL SHEET AND STRENGTH PART FOR AUTOMOBILE UTILIZING THE SAME - There is provided an ultrahigh strength steel sheet containing 0.10 to 0.40 mass % of C, 0.01 to 3.5 mass % of Cr, at least one selected from the group consisting of 0.10 to 2.0 mass % of Mo, 0.20 to 1.5 mass % of W, 0.002 to 1.0 mass % of V, 0.002 to 1.0 mass % of Ti and 0.005 to 1.0 mass % of Nb, 0.02 mass % or less of P and 0.01 mass % or less of S as impurities and the balance being Fe and unavoidable impurities based on the total mass of the steel sheet and having a base structure of lower bainite, a prior austenite grain size of 30 μm or smaller and a tensile strength of 980 MPa or higher. There is also provided an automotive strength part using the ultrahigh strength steel sheet. | 09-24-2009 |
| 20100051144 | EXCELLENT COLD-WORKABILITY EXHIBITING HIGH-STRENGTH STEEL, WIRE OR STEEL BAR OR HIGH-STRENGTH SHAPED ARTICLE, AND PROCESS FOR PRODUCING THEM - There are provided an excellent cold-workability exhibiting high-strength steel wire or steel bar, or high-strength shaped article and a process for producing them. In particular, there is provided a process comprising carrying out hot working at 350 to 800° C. of a steel ingot, cast slab, steel slab or steel semifinished product having a C content of not greater than the solid solution limit of carbon of ferrite phase at Ae | 03-04-2010 |
| 20100173716 | FORMED PRODUCT AND METHOD FOR PRODUCTION THEREOF - A formed product, characterized in that it is produced by using, as a material, a steel having an ultra fine structure comprising ferrite grains having an average grain diameter of 3 μm or less and by a method comprising only a forming step and including none of refining steps; and a method for producting the above formed product with ease. The formed product contains no alloying element and has been subjected to no refining step, and has been imparted with high strength and high toughness by the above ultra fine structure. | 07-08-2010 |
| 20110083775 | HEAVY WALL STEEL MATERIAL HAVING SUPERIOR WELDABILITY AND METHOD FOR PRODUCING THE SAME - A tough high strength heavy wall steel material having superior weldability is provided, said steel material has a diameter or a side 5 mm or more in length, and comprises oxides 1 μm or less in particle diameter homogeneously dispersed at a dispersion density in a range of from 10,000 to 100,000 particles/mm | 04-14-2011 |
| 20110303655 | WELDING EQUIPMENT FOR METALLIC MATERIALS AND METHOD FOR WELDING METALLIC MATERIALS - A welding equipment for metallic materials capable of performing heat treatment such as tempering based on partial heating in spot welding is provided. The welding equipment | 12-15-2011 |
| 20120118440 | HIGH-STRENGTH AND HIGH-DUCTILITY DIE-QUENCHED PARTS AND METHOD OF MANUFACTURING THE SAME - A high-strength die-quenched part | 05-17-2012 |
