On the sampling in the case of the investigation for earing in deep drawing used one way cold-rolled aluminium sheet

Abstract

When the study on the earing in the process of deep-drawing is made, the blank is oftenly taken from the sheets which are rolled in the early stage of the operation of rolling, when the temperature of roll as well as the other parts of machine is as almost same as the room temperature. But, after the rolling operation gets into stationary state in contenuons work, the temperature of the roll gets naturally higher. If so, the earing phenomenon may also be different between the blanks taken in early stage and stationary stages of rolling operation.
This is to report on the result of the experiment to compare these two. It is found out that the difference as stated above, is recogniged as the cold reduction is increased. It is, therefore, considered that this fact should be taken into consideration when the specimen is taken for examining the earing phenomenon in deep-drawing operation.