PURPOSE: To reduce friction coefficient by performing a composite plating for which solid fine particles having a hardness not lower than a specific Vickers hardness are dispersed on the surface of a work roll by using hard Cr, etc., as a matrix and cold rolling a rolled steel sheet with neat oil or an emulsion of water and oil spraying onto the sheet.
CONSTITUTION: A composite plating is applied onto the surface of a work roll by using Ni, Ni-P, Cu, hard Cr, Fe, Co or Ni-Co as a matrix. The composite plating is such that one or more kinds of solid fine particles having a Vickers hardness of ≥900 are dispersed in the plating layer. Cold rolling is performed by the work roll and spraying neat oil or an emulsion of water and oil onto a rolled steel sheet. At the time of contacting the sheet with the roll surface, actual contact is generated between the sheet and solid fine particles on the outermost surface. Hence, a friction coefficient between the sheet and roll is reduced, service life of the roll is prolonged as well as high speed rolling is performable without making surface quality of the sheet worse.
KATO OSAMU
NAKAMURA KAZUO
YAMAMOTO KUNIYASU
| JPS6333108A | 1988-02-12 |