Cast Iron Mach Inability: The Effect of Aging on Material Properties Determines the Optimal Machining Time
Understanding how age strengthening affects machinability enables manufacturers to schedule the optimal window for machining. Aging studies in quenched iron-based alloys indicated a three stage precipitation process. In some cases, a dip in strength is observed during the start of the aging process. The machinability test articles recommended by the American Foundry Society were used for facing cuts on a computer numeric control lathe. These test articles were produced in a laboratory using nobake molds and in industrial metalcasting facilities using green sand molds. Pearlite/ferrite cast irons with variations in carbon equivalent from 3.9% to 4.3% were tested in as-cast condition and after 25 days of natural aging. A reverse type of dependency appeared in which the cutting force decreased when the increasing hardness was due only to natural aging in each iron.
S. N. Lekakh and V. Richards, "Cast Iron Mach Inability: The Effect of Aging on Material Properties Determines the Optimal Machining Time," Metal Casting Design and Purchasing, vol. 15, no. 5, pp. 25-29, American Foundry Society, Sep 2013.
Materials Science and Engineering
Keywords and Phrases
Age strengthening; American foundry societies; Carbon equivalent; Computer numeric control; Machinability tests; Metalcasting facilities; Optimal machining; Precipitation process; Optimization; Precipitation (chemical); Cast iron
International Standard Serial Number (ISSN)
Article - Journal
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