Quantitative Characterization of the Affected Zones in a Single Crystal Fe-6Si Steel Sheet by Fine Piercing

Abstract

An iron loss in the motor core was often enhanced by formation of plastically affected zones in piercing the electrical steel sheets. A platform methodology to carry out quantitative evaluation of these affected zones in the pierced electrical steel sheets was proposed to search for the way to minimize the affected zone widths. A coarse-grained electrical steel sheet was employed as a work material for a fine piercing experiment under the narrowed clearance between the plasma-nitrided SKD11 punch and core-die. The shearing behavior by the applied loading for piercing was described by in situ measurement of the load-stroke relationship. The plastic straining in the single-crystal electrical steel sheet was characterized by SEM (scanning electron microscopy) and EBSD (electron back-scattering diffraction) to define the affected zone size and to analyze the rotation of crystallographic orientations by the induced plastic distortion during piercing. Integral and differentiation of spin rotation measured the affected zones. The effect of punch edge sharpness on these spin-rotation measures was also discussed using the nitrided and ion-milled SKD11 punch and core-die.

Plasma Nitriding-Assisted 3D Printing for Die Technology in Digital Micro-Manufacturing

“…Then, an ion milling is employed to finish the edge width down to 1 μm or less than. As reported in [57,58], the edgesharpened punch and die with higher hardness than 1000 HV by the plasma nitriding has a capacity to improve the quality of sheared surfaces without loss of die life.…”

Fine Blanking of Austenitic Stainless Steel Gears Using Carbon-Supersaturated High-Speed Steel Tools

“…In the similar manner to the post-treatment of thick DLC and diamond coatings, the plasma carburized layer has enough thickness to be post-treated for adjusting the punch edge profiles without deterioration to in situ solid lubrication mechanism in the above. In fact, the edge profile of plasma nitrided SKD11 punches was post-treated to have sharpness enough to improve the punching behavior of electrical steel sheets [25].…”

Massive Nitrogen Supersaturation to CoCrMo alloys for Surface Microstructure Control

“…The derivative of  or  was calculated from the difference of  between the neighboring measurement points along the specified line. This  value is sensitive to the crystallographic change in local as stated in [21].…”

“…The integral of , or , was also calculated by the accumulation of  from the surface to the end along the specified line. This  depicts the gradual change in the crystallographic structure [21].…”