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The wide applications of deep drawing (DD) steel sheets specifically for the automobile industry are well-known, but their quality control is dependent on empirical engineering simulative tests like the Erichsen cup test, Olsen cup test and Hole-expansion tests [1,2]. The principles of the above tests, in general, attempt to search for an engineering parameter which indicates the mechanical environment for crack initiation and/or propagation under the corresponding experimental condition for each of these tests. The event of crack initiation and propagation is commonly dealt with using fracture mechanics principles; but so far little attention has been paid in this direction. Only Liu and his co-workers [3][4][5] have suggested some guidelines to assess fracture criteria of thin and tough plates of structural materials.The salient conclusions of these reports [3][4][5] indicate that the near tip strain or the crack-tip contraction can be used as a fracture criterion for thin plates of ductile and tough materials. But such analyses were conducted primarily on HY-80 steel plates having thicknesses in the range 1.58-12.3 mm, the upper limit of which is well beyond the maximum thickness limit (-5 mm) of sheet metals. In addition, the experimental techniques involved in those investigations [3][4][5] are too elaborate in nature to employ them for quality control of sheet metals when characterizing their formability and drawability potentials in terms of fracture mechanics based criteria. The objectives of this report are (i) to present a simple technique for obtaining fracture criteria of DD steel sheets following the studies of Liu and co-workers [3-5] and (ii) to examine the effect of the variation of thicknesses of such steel sheets on their fracture criteria.The composition of the investigated steel is given as (C-0.06, Mn-0.38, S-0.03, P-0.017, Si-0.05, Fe-Bal., all in weight %). The microstructure of the material revealed ferrite plus pearlite (-5.1%), and the average ferrite grain size was found to be 7.2 l.tm. The cleanliness assessment of the steel indicated volume fracture of inclusions to be less than 0.1%. The average tensile properties of the material were as follows: yield strength (~)-335.9 MPa, ultimate tensile strength-387 MPa, uniform elongation-24.4% ~/nd total elongation-25.9%. The average hardness of the steel in the Rockwell-B scale was obtained as 71.3. FractureVO (1994) Int Journ of

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