Novel austenite ductile cast iron production and improvement technique

Abstract

The invention discloses a novel austenite ductile cast iron production and improvement technique. The austenite ductile cast iron comprises the following components in parts by mass: 2.5-2.6% of C, 4.6-4.8% of Si, 0.55-0.65% of Mn, 19-20% of Ni and 1.55-1.65% of Cr. In the smelting production process, the austenite ductile cast iron is prepared from the following components in parts by mass: 58% of returns, 30.95% of pig iron, 7.7% of nickel plate, 2% of 75A silicon iron, 0.25% of electrolytic manganese and 1.1% of chromium iron. The technique has the characteristics of low cost and wide application range, and the normal-temperature static properties and high-temperature dynamic properties can respectively reach or exceed the requirements for high-nickel ductile cast iron. The austenite ductile cast iron has the advantages of reasonable proportioning, stable performance, higher flowability and cavity filling capacity of molten iron, lower shrinkage porosity tendency of the casting, and obviously higher normal-temperature static properties, achieves the goal of dual optimization of cost and performance, can ensure the quick performance of production, and enhances the production efficiency.

Description

technical field [0001] The invention belongs to the technical field of metal material production, and in particular relates to a novel austenitic nodular iron production and improvement process. Background technique [0002] Austenitic ductile iron is composed of austenite matrix, spherical graphite and carbide. Since nickel can be infinitely dissolved in iron, as long as there is enough addition, a single austenite structure can be obtained at room temperature. Generally, austenitic ductile iron has good mechanical properties at room temperature, high temperature creep limit, excellent thermal shock resistance, corrosion resistance and high temperature oxidation resistance, so it is widely used in automobile exhaust pipes and turbocharger shells Body, industrial boiler and other high temperature environment. [0003] In the existing austenitic ductile iron castings, in order to pursue the superiority of performance, high-nickel parts are often used. The invention with ...

AI Technical Summary

Problems solved by technology

[0004] Take GGG-NiSiCr3552, the most widely used German brand at present, as an example. It is known as one of the materials with the best performance in austenitic ductile iron, but it has the same nickel content as the above-mentioned types. High disadvantages, about 25% to 35%, make these types of ductile irons too expensive, difficult to be widely used in automobile exhaust pipes, and only used on some important parts, so a combination with GGG-NiSiCr3552 is needed A lower cost alternative with similar performance, allowing it to be widely used in metal castings