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苏联曾研究了高强度球铁的流体动力学热挤压方法。这种方法目前在机器制造业中巳得到广泛的应用,并在许多情况下,有效地代替着轧钢件。使用非合金的球铁试样其化学成份为:3.46%C;2.47%Si;0.46%Mn;0.08%P;0.009%S;0.056%Mg。采用低硫炉料(精炼的铸造生铁和废钢)在HCT-016犁感应炉中熔炼,出铁温度为1520℃。在六个大气压的高压釜中用0.1%的金属镁进行球化处理。浇注之前,用0.5%的75%—硅铁进行孕育,然后在湿型中浇注φ30毫米的圆柱试棒。在进行流体动力学热挤压之前,将一批毛坯件先经过940±10℃,保温2小时的正火处理,并在530±10℃,保温2.5小时,进行高温回火。热处理后,试样的金属基体由索氏体珠光体和少量(<3%)铁素体组成。石墨为球形,试样的硬度HB=269～275。
The Soviet Union has studied hydrodynamic hot extrusion of high-strength ductile iron. This method is currently used extensively in machine building and, in many cases, effectively replacing rolled steel. The chemical composition of the non-alloyed ductile iron sample is 3.46% C, 2.47% Si, 0.46% Mn, 0.08% P, 0.009% S and 0.056% Mg. Low-sulfur charge (refined cast iron and scrap) is melted in an HCT-016 plow induction furnace with a tapping temperature of 1520 ° C. Spheroidization was performed with 0.1% metallic magnesium in a six-atmosphere autoclave. Prior to casting, it is inoculated with 0.5% 75% ferrosilicon and then a φ30 mm cylindrical test rod is placed in a wet form. Prior to hydrodynamic hot extrusion, a plurality of blanks were first subjected to normalizing at 940 ± 10 ° C for 2 hours and holding at 530 ± 10 ° C for 2.5 hours for high temperature tempering. After heat treatment, the metal matrix of the sample consisted of sorbite pearlite and a small amount (<3%) of ferrite. Graphite is spherical, sample hardness HB = 269 ~ 275.