Development of the 600MPa High Aluminum Galvanized Dual Phase Steel and its Application
An original 600MPa high aluminum galvanized dual phase steel had been successfully developed in this paper. The microstructure analysis showed that the microstructures of the steel mainly consist of ferrite and 8%~11% martensite as well as 4%~6% retained austenite which distributed around the ferrite grain boundaries. TEM analysis demonstrated that there exists lots of high density dislocation in ferrite, obvious twin-structures in martensite and some retained austenite in the microstructures. The existence of the retained austenite makes some contribution to the higher elongation of the steel. The tensile test showed that the steel delivers an excellent mechanical properties of Rp0.2=350~400MPa,Rm=610~650MPa, A80mm=26%~30%, n=0.17~0.21 and an excellent bake-hardening value of 50~70MPa. Ball-Punch Experiments showed that the galvanizing dual phase steel had a good and satisfying coating adhesion. Owe to the excellent formability, the steel has successfully been used in the production of some auto parts.
H. Wang et al., "Development of the 600MPa High Aluminum Galvanized Dual Phase Steel and its Application", Advanced Materials Research, Vols. 228-229, pp. 1169-1173, 2011