SU827579A1 - Modifier - Google Patents

Description

one

The invention relates to metallurgy and can be used in the production of high-strength nodular cast iron (HDF).

Known modifier for cast iron, containing, in weight. %: magnesium 3-5, graphite 8-10, iron the rest 1.

The use of this modifier does not provide stable results in obtaining pearlite base in the cast iron structure due to the presence of free graphite in castings with wall thicknesses of 50-70 mm and higher in the central zones of thermal nodes, spheroidal graphite inclusions are degraded and different types of compact graphite of irregular shape are released. Castings have insufficient ductility and strength.

The closest to the invention in technical essence and the effect achieved is a modifier of the following composition, weight. %: Magnesium

15-45 Barium

0.5-10 Graphite

2-10 Copper

The rest of this modifier partially eliminates the disadvantages of the above, but the degradation of inclusions of graphite of spherical shape and the release of graphite of irregular shape are not suppressed.

The aim of the invention is to suppress the degradation of spherical graphite and increase the strength of the iron.

The goal is achieved by the fact that the proposed modifier additionally contains nickel and ferrosilium in the following ratio of components, weight. %:

Magnesium 15-45

Barium2-10

Graphite2-10

Nickel5-10

Ferrosilicium Else

Example. The original cast iron containing, weight. %: carbon 3.2 / 3.5; silicon 1.8-2.3; manganese 0.45-0.65; sulfur 0.08-0.12; phosphorus 0.12-0.14, modified by the proposed and known modifier.

Samples and experimental details of woodworking machines, having in their construction thin parts in combination with massive 50X70 mm, in which thermal units are located, were cast and investigated.

Samples for determining the characteristics of cast iron were cut from the zones of thermal nodes most susceptible to the disintegration of the spherical shape of graphite and, consequently, the deterioration of mechanical properties.

The results of the experiments are presented in the table. Note. The compositions correspond to the prototype, 4-

Claims (2)

Invention Formula The modifier, containing, magnesium, barium, graphite, characterized in that, in order to suppress the degradation of nodular graphite inclusions and increase the strength of cast iron, it additionally contains nickel and ferrosilicon at the next component ratio, weight. %: Magnesium15-45 Barium2-10 Graphite2-10 Nickel5-10 Ferrosilicium Else Sources of information taken into account during the examination 1. USSR author's certificate 461124, class C 22C 35/00, 1973. 2. USSR author's certificate 577248, cl. C 22C 35/00, 1977. 6 the proposed modifier.