Formability of Micro Sheet Hydroforming of Ultra-fine Grained Stainless Steel

• Published in: Procedia engineering Vol. 81; pp. 1463 - 1468
• Main Authors: Sato, Hideki, Manabe, Ken-ichi, Kondo, Daiki, Wei, Dongbin, Jiang, Zhengyi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 2014
• Subjects: Formability; Micro hydromechanical deep drawing; Micro sheet hydroforming; Ultra-fine grain; Micro sheet hydroforming; Formability; Micro hydromechanical deep drawing; Ultra-fine grain
• ISSN: 1877-7058; 1877-7058
• DOI: 10.1016/j.proeng.2014.10.174

The formability of ultra-fine grained stainless steel is investigated in micro hydromechanical deep drawing. The materials used are ultra-fine grained stainless steel and SUS304-H with thickness of 20 and 50μm. The micro cups are successfully fabricated for the ultra-fine grained stainless steel but it cannot be fabricated for SUS304-H with thickness of 20μm. The fracture type of ultra-fine grained stainless steel foil is the shortage of tensile strength at plain strain state and does not change with a decrease of the thickness. In contrast, the fracture type of SUS304-H foil changes to the bending deformation with decreasing the thickness due to its low ductility. The ultra-fine grained metal foil is required to obtain the high formability and fabricate the sharp micro cups.