AbstractThe crack propagation that occurs in corrugated board in connection with die cutting is analysed in order to identify the most crucial liner and fluting parameters and clarify their relative importance.Based on an energy approach and the brittleness concept —Lc‐1(m‐1) —for the liner, a formula is derived. This formula is then verified exeprimentally for a large number of corrugated board qualities of different thicknesses and flat crush strengths as well as for liners with widely differing mechanical properties. The correlation can be regarded as very good.The analysis shows that crack propagation is dependent on three material parameters —the brittleness of the liner, the compression strength of the fluting in relation to the tensile strength of the liner and the breaking strain of the liner. It is shown that crack propagation increases proportionally with increasing liner brittleness, provided that the other material parameters remain unchanged. The compression strength of the fluting layer contributes somewhat more than proportionally — by a power of 1.33. The crack propagation decreases with increased breaking strain, the relation is almost inversely proportional.In practice, none of the above mentioned liner parameters car. be chosen independently of the others. The same applies to the fluting parameters. When estimating the expected crack propagation in a particular corrugated board quality, it is necessary to consider the contribution from all the mentioned parameters according to