A series of micro-deep drawing experiments were conducted on stainless steel 304 foils with four thicknesses that were heat treated at four different temperatures. Due to heat treatments, a variety of different grain sizes and T/D ratios (the number of grains throughout thickness) were obtained. In this study, the limit drawing rations (LDR) of these foils were obtained; it has also been found that the factors that influence LRD of the foils include, but are not limited to, thickness, grain size, and T/D ratios. Tensile tests were conducted to obtain their mechanical properties that were used for two macroempirical equations to predict the maximum drawing load and LDR. It has been verified that the two equations can be applied to foils that are not thinner than 150 m for reasonable predictions. However, the size effects are more noticeable and significant for the foils that are less than or equal to 100 m so that the macroscale empirical equations cannot be applied to them.

Tensile test and a micro stretch bending test were conducted to study the behavior of the stainless steel 304 foils for micro sheet forming. In this study, 4 different thicknesses stainless steel 304 foils were used as specimens while 5 micro deep draw dies were used for micro stretch bending experiments. By observing the tensile test results, it can be found that the stainless steel 304 foils with T/D (thickness/average grain diameter: the numbers of grains throughout the metal thickness) <10 has less formability than those with T/D>10. By observing the results of the micro stretch bending experiments, it can be concluded that the stainless steel foils with T/D>10 have less springback amount and smaller springback deviation in comparison with those with T/D<10. In order to have a better formability and less springback, it is recommend having the stainless steel 304 foils with T/D>10 for micro sheet forming application.