SU1461584A1 - Composition for surface alloying of castings - Google Patents

Abstract

The invention relates to a foundry, namely, compositions for alloying the surface of cast iron castings. The purpose of the invention is to increase the heat resistance and wear resistance of the working surface of cast iron molds. The composition for surface alloying of castings includes powdered alloying filler, binder and flux. The goal is achieved by addition of manganese to the composition of the alloying filler containing iron, carbon and vanadium in the following ratio of ingredients, wt.%: Carbon 0.1 - 0.5; vanadium 4-16; manganese 10-26; iron else. This ensures the complex doping of the surface layer of castings with vanadium and manganese and obtaining in it a structure consisting of a highly plastic austenitic metal base with inclusions of hard carbide particles. This structure gives the alloyed layer high heat resistance and wear resistance. The use of the composition improves the service resistance cast iron forms - chill molds. 2 tab. about s (/ c

Description

The invention relates to a foundry, namely, compositions for alloying the surface of iron castings.

The purpose of the invention is to increase the heat resistance and wear resistance of the working surface of cast iron molds.

The working surface of cast-iron molds is alloyed with a composition comprising powdered alloying. filler, binder and flux.

The essence of the invention lies in the additional introduction of manganese into the known composition of the alloying filler containing iron, carbon and

vanadium, in the following ratio of ingredients, wt.%: carbon 0.1-0.5; vanadium, 4-16; manganese 10-26; iron else. Introduction to the composition of the alloying filler - Mar1: .tank within the specified limits ensures that in the working layer of cast-iron forms of the doped layer, with an austenitic matrix. With complex doping with manganese and vanadium, a structure consisting of inclusions of carbide particles in a metal matrix is formed in the surface layer. The combination of highly plastic in the wide temperature range of the metal base (austenitic

SP

ate

matrix) and reinforcing its dispersed particles of carbides, which are characterized by high hardness, gives the alloyed layer high heat resistance and wear resistance.

The composition is prepared from 88-93 wt.% Powdered legiruyu tse filler fraction of 0.2-1.5 mm, 3-6 wt.% Flux. In the form of a mixture of boron oxide, borax and potassium chloride in a ratio by weight of 4: 3: 4 and 4-6 wt.% Of the old glass.

The compositions for surface alloying are listed in the table.

Flux components are used in a finely divided state with a specific surface area of particles of at least 1500. The ingredients of the composition are mixed and diluted with water until a homogeneous suspension is obtained.

The latter is applied to the surface of molds with a thickness of mm. The molds are poured with a C-420 gguun at 1250-1270 ° C, and castings are obtained in the form of plates with a thickness of 40 mm and a mass of 20 kg,

Variants of the compositions and parameters of the properties of the doped layer on the surface of the castings are given in Table 2;

The introduction of manganese into the composition of the doped o11 (ago filler J containing iron and vanadium) allows to obtain castings with a doped layer that combines high thermal resistance and wear resistance.

The use of the invention in the manufacture of molds for casting pallets provides an increase in their durability by about 2 times. The resulting positive effect is due to a decrease in the specific consumption of the chill mold of 16j8 kg per 1 ton of suitable casting.

Claims (1)

Invention Formula The composition for surface alloying of castings is predominantly the working surface of cast iron forms including 4-6% by weight of binder and 3-6% flux and powdered iron based iron filler with carbon and vanadium - the rest j from l and h that, with; in order to increase the heat resistance and the nose resistance of the working surface of the cast-iron molds 5 to the alloyer; osh; the filler additionally contains manganese in the following ratio of ingredients of the filler J wt,%: Carbon. Oh, 1-0.5 Vanadium4-16 Manganese10-26 Iron.The rest Ingredients The quantitative content, in wt%, in the compositions nZIIIZELlEIIII Alloying filler .90.3 90.3 90.3 90.3 90.3 89.3 92 Spreadsheets 89 table 2 After 300 cycles of testing in the mode: heating the end alloyed surface in lead melt to 840-850 ° C, then cooling with water up to 90-100 from the opposite undoped end surface of a cylindrical specimen 0 40-20 mm Ratio of wear resistance compared to steel Art. 2 Continuation of table 2