Shock drawing of thin plates by use of dry-ice projectiles (3rd report, transformation of metallic structure of shock-drawn plates)

In the preceding two papers, the shock drawing of thin circular plates using high-speed dry-ice projectiles was investigated experimentally and by numerical simulation. the austenite stainless steel SUS 304 used in the experiments is partially transformed into the martensite structure by machine processing, and ferrite is deposited according to the degree of strength of the machine processing. In this study, the distribution of ferrite content of the shock-drawn plates is measured and microscopic observations are made in order to estimate the shock load in the drawing process.