Abstract: A high ductility machinable cast iron with mixed austenitic-bainitic structure is made by a method which involves limiting the manganese content to less than 0.3% by weight and utilizing a substantially lower temperature austenitizing heat treatment (820.degree. to 830.degree. C.) for a shorter period (10 to 25 minutes) than has hitherto been considered to be necessary to achieve such structures. The low alloy cast iron can therefore be made from available scrap with low manganese content and at low cost.
Type:
Grant
Filed:
December 16, 1983
Date of Patent:
September 17, 1985
Assignee:
Horst Muhlberger
Inventors:
Horst Muhlberger, Bruno Prinz, Wolf Wunder, Ulrich Schafer, Josef Bognar