SHUTTER MATERIAL FOR CARTRIDGE

摘要

PURPOSE:To obtain a shutter material for cartridge having excellent appearance in which flaw does not occur due to scraping of steel plates, press work can be carried out well, and no dust is produced during usage. CONSTITUTION:Vickers hardness Hv is set at 220-350 in the center of thickness of a steel plate while setting higher than 250 in the superficial part. Surface roughness of the steel plate is set such that the center line average roughness Ra is higher than 0.3mum while the roughness Ra of the rear surface subjected to dull finish is in the range of 0.1-0.25mum.