Masafumi Azuma

Spot-welded joint and spot welding method

High-strength hot-dip galvanized steel sheet and hot-dip galvannealed steel sheet having fatigue resistance, corrosion resistance, ductility and plating adhesion, after severe deformation, and a method of producing the same

High-strength steel sheets which are extremely excellent in the balance between burring workability and ductility and excellent in fatigue endurance, zinc-coated steel sheets, and processes for production of both

HIGH-STRENGTH STEEL SHEET HAVING EXCELLENT HYDROGEN EMBRITTLEMENT RESISTANCE AND MAXIMUM TENSILE STRENGTH OF 900 MPa OR MORE, AND PROCESS FOR PRODUCTION THEREOF

High-strength galvanized steel sheet, high-strength alloyed hot-dip galvanized sheet, and high-strength cold-rolled steel sheet which excel in moldability and weldability, and manufacturing method for the same

High-strength steel sheet and galvanized steel sheet having very good balance between hole expansibility and ductility, and also excellent in fatigue resistance, and methods of producing the steel sheets

HIGH STRENGTH STEEL PLATE WITH ULTIMATE TENSILE STRENGTH OF 900 MPa OR MORE EXCELLENT IN HYDROGEN EMBRITTLEMENT RESISTANCE AND METHOD OF PRODUCTION OF SAME

HIGH-STRENGTH COLD-ROLLED STEEL SHEET, HIGH-STRENGTH GALVANIZED STEEL SHEET, AND HIGH-STRENGTH ALLOYED HOT-DIP GALVANIZED STEEL SHEET HAVING EXCELLENT FORMABILITY AND WELDABILITY, AND METHODS FOR MANUFACTURING THE SAME

High-strength galvanized steel sheet and method of manufacturing the same

High-strength hot-dipped galvanized steel sheet and high-strength alloyed hot-dipped galvanized steel sheet, each having tensile strength of 980 mpa or more, excellent plating adhesion, excellent formability and excellent bore expanding properties, and method for producing same