A METHOD FOR MANU- FACTURING ALLOYED HOT DIP GALVANIZED STEEL SHEET FOR HOT PRESS FORMING HAVING EXCELLENT PLATING ADHESION AND IMPACT PROPERTY, THE METHOD FOR MANUFACTURING HOT PRESS PARTS MADE OF IT

摘要

is used primarily as a structural member or a reinforcement of the car body, coating adhesion and impact properties superior machining alloyed hot forming Preparation method of hot-dip galvanized steel sheets and hot forming part of the manufacturing method using this plate there is provided a ; to the production method of the steel sheet is weight%, C: 0.1 ~ 0.5%, Si: 0.01 ~ 1.0%, Mn: 2.0 ~ 4.0%, P: less than 0.1%, S: less than 0.03%, soluble Al: not more than 0.1%, N: 0.01 ~ 0.1%, W: 0.1% or less, the composition in balance of Fe and other unavoidable impurities that steel slab reheating at 1100 ~ 1300 , and, Ar ₃ in the transformation temperature above 1000 or less shut down the hot finish rolling, and then wound at 500 ~ 750 , pickling and cold rolling, and then, for less than 10 seconds at a temperature range of 450 ~ 470 subjected to hot-dip galvanizing, cooling to room temperature, in a temperature range of 440 ~ 580 alloying heat treatment is carried out in less than 30 seconds. ; According to the present invention, the coating adhesion is excellent, and after hot forming and coating of 1470MPa or more ultra-high strength after hot forming machining alloy having a yield strength of 100MPa or more rate-dip galvanized steel sheet production process and the steel plate Using it is possible to provide a method of manufacturing a hot-molded part.