Spheroidal graphite cast iron

Abstract

Abstract PURPOSE: To manufacture a spheroidal graphite cast iron having high impact value at low temp. in the as-cast state, by adding specific amounts of Bi to a molten metal in which specific amounts of C, Si, Mn, P, Cr, and Mg are incorporated to iron and also CE value is specified and then applying inoculation so as to regulate the number of graphite grains to a specific value. CONSTITUTION: Bi is added by 0.005W0.03%, by weight, to a molten metal consisting of 3.0W4.0% C, 1.5W2.3% Si, <0.3% Mn, <0.03% P, <0.10% Cr, 0.02W0.06% Mg, and the balance iron with inevitable impurities. Simultaneously with or after the Bi addition, inoculation is carried out to regulate the number of graphite grains to 300 piece/mm 2 and, if necessary, residual Bi content is also regulated to 0.0015W0.0150%. By this method, the spheroidal graphite cast iron capable of securing sufficient elongation and impact value at low temp. by means of short-time heat treatment can be obtained. COPYRIGHT: (C)1989,JPO&Japio

Inventors

• 👤 Yasuoki Ishihara
• 👤 Fumio Obata
• 👤 Jun Sakai
• 👤 Takeshi Natsume

Bibliographic Details