Hot Dip Plated Steel Sheet Having Excellent Plating Adhesiveness and Method of Manufacturing the Same

Abstract

Provided is a hot dip plated steel sheet used in automotive materials and a method of manufacturing the same, and more particularly, to a hot dip plated steel sheet having excellent platability and plating adhesiveness in which a steel sheet containing alloying elements forming oxides on a surface of the steel sheet at high temperatures is used as an underlying steel sheet, and a method of manufacturing the same. According to the present invention, a hot dip plated steel sheet having excellent platability and plating adhesiveness is provided, in which a steel sheet containing alloying elements forming oxides on a surface of the steel sheet at high temperatures is used as an underlying steel sheet, and thus, limitations in added amounts of silicon (Si), manganese (Mn), or aluminum (Al) may be mitigated. Therefore, development of new steels may be accelerated.

1 . A hot dip plated steel sheet having excellent plating adhesiveness comprising:
 a steel sheet containing alloying elements forming oxides on a surface of the steel sheet at high temperatures as an underlying steel sheet; and   a plating material plated on the underlying steel sheet,   wherein a discontinuous reduced iron (Fe) layer and a Fe-plating material alloy phase are formed at an interface of the underlying steel sheet and a plating layer.   
     
     
         2 . The hot dip plated steel sheet having excellent plating adhesiveness of  claim 1 , wherein the underlying steel sheet comprises one or more alloying elements of silicon (Si), manganese (Mn), and aluminum (Al). 
     
     
         3 . The hot dip plated steel sheet having excellent plating adhesiveness of  claim 1 , wherein the underlying steel sheet is any one of a dual phase (DP) steel, a transformation induced plasticity (TRIP) steel, a complex phase (CP) steel, a martensitic (MART) steel; and a twinning induced plasticity (TWIP) steel. 
     
     
         4 . The hot dip plated steel sheet having excellent plating adhesiveness of  claim 1 , wherein the plating material comprises one or more of zinc (Zn), aluminum (Al), and magnesium (Mg) as main components. 
     
     
         5 . The hot dip plated steel sheet having excellent plating adhesiveness of  claim 1 , wherein a discontinuous Si—Mn oxide layer is formed between the underlying steel sheet and the plating layer. 
     
     
         6 . The hot dip plated steel sheet having excellent plating adhesiveness of  claim 1 , wherein the Fe-plating material alloy phase is distributed within a thickness of 60% of a total thickness of the plating layer from the interface of the plating layer and the underlying steel sheet to a direction of a surface of the plating layer. 
     
     
         7 . The hot dip plated steel sheet having excellent plating adhesiveness of  claim 1 , wherein a discontinuous Al—Fe inhibition layer is distributed between the underlying steel sheet and the plating layer. 
     
     
         8 . The hot dip plated steel sheet having excellent plating adhesiveness of  claim 1 , wherein a Si—Mn internal oxide is distributed up to a depth of 7 μm from the interface of the plating layer and the underlying steel sheet to an inner direction of the underlying steel sheet. 
     
     
         9 . A method of manufacturing a hot dip plated steel sheet having excellent plating adhesiveness, the method comprising:
 oxidizing a steel sheet containing alloying elements forming oxides on a surface of the steel sheet at high temperatures by using a direct fired furnace at an air/fuel ratio or an air/gas ratio range of about 1.01 to about 1.5 and a steel sheet temperature range at an exit of the direct fired furnace of about 550° C. to about 750° C.;   performing reduction annealing and hot dip plating; and   performing a slight annealing treatment in a temperature range of 400° C. to about 550° C.   
     
     
         10 . The method of  claim 9 , wherein an underlying steel sheet comprises one or more of silicon (Si), manganese (Mn), and aluminum (Al). 
     
     
         11 . The method of  claim 9 , wherein the underlying steel sheet is any one of a dual phase (DP) steel, a transformation induced plasticity (TRIP) steel, a complex phase (CP) steel, a martensitic (MART) steel, and a twinning induced plasticity (TWIP) steel. 
     
     
         12 . The method of  claim 9 , wherein a temperature of the slight annealing treatment is within a range of 440° C. to about 500° C. 
     
     
         13 . The method of  claim 9 , wherein the plating material comprises one or more of zinc (Zn), aluminum (Al), and magnesium (Mg) as a main component.