Hot galvanizing alloyed H220BD steel plate with uniform pores and low surface waviness and preparation method of hot galvanizing alloyed H220BD steel plate

The invention discloses a hot-dip galvanized alloyed H220BD steel plate with uniform pores and low surface waviness and a preparation method of the hot-dip galvanized alloyed H220BD steel plate. The steel plate comprises the following chemical components in percentage by weight: 0 < C < = 0.003%, 0.04% < = Si < = 0.08%, 0.25% < = Mn < = 0.65%, 0.03% < = P < = 0.07%, 0 < S < = 0.012%, 0 < N < = 0.005%, 0.02% < = Al < = 0.08%, 0 < Cr < = 0.06%, 0.001% < = Nb < = 0.006%, 0 < Ti < = 0.01%, 0 < Ni < = 0.06%, 0 < B < = 0.0005%, wherein N * 48/14/2lt; tilt, Tilt; n * 48/14, Algt; (N-Ti * 14/48) * 27/14, 10 ppm < = C-Nb * 12/93 < = 18 ppm, and the balance Fe and inevitable impurities. According to the invention, the hot-dip galvanized alloyed bake-hardened steel plate with uniform pore structure, surface waviness Wsa of less than or equal to 0.35 mu m after 5% stamping deformation and yield strength of 220Mpa grade is obtained through the processes of effectively blending key alloy elements, accurately designing anne