SU1611974A1 - Wear-resistant alloy - Google Patents

Abstract

The invention relates to the metallurgy of iron-based alloys, in particular to materials for the production of components and parts subjected to dynamic loads during operation under conditions of intense abrasive wear, for example, grinding bodies and armor lining plates of tube mills. The aim of the invention is to increase ductility and crack resistance while maintaining the level of impact-abrasive wear resistance. The alloy contains, wt%: carbon 2.8-3.8

silicon 1.5-2.5

manganese 1-5

nickel 0.5-2.5

chrome 8-12

aluminum 0.05-0.15

titanium 0.05-0.15

vanadium 1-0.5

boron 0,005-0,05

calcium 0.03-0.15

antimony 0,008

iron is the rest, while the ratio of manganese and nickel is 2: 1. The introduction of the proposed alloy into production ensures the production of castings with a high level of plasticity, crack resistance and impact-abrasive wear resistance, which contributes to improving the quality of parts during production and increasing durability during operation. The service life of the wearing parts and parts of the crushing and milling equipment (armor plates, partitions, grinding bodies, etc.) from the proposed alloy increases by 50-70%. 2 tab.

Description

The invention relates to the metallurgy of iron-based alloys, in particular to the search for materials for the production of components and parts subjected to dynamic loading during operation under conditions of intense abrasive wear, for example, grinding mills and armored plates of tube mills.

The aim of the invention is to improve ductility and crack resistance while maintaining the level of impact-abrasive wear resistance.

The goal is achieved in that the alloy contains carbon, silicon, manganese, chromium, vanadium, nickel, aluminum, titanium, boron, antimony, and iron in the following ratio of components, May .:

Carbon Silicon Manganese

2.8-3.8

1.5-2.5

 1.0-5.0

 0.5-2.5 8-12, 0.05-0.15 0.05-0.15 O, -1-0.5 0.005-0.05 0.03-0.15 0.005-0.05 Rest

and the ratio of manganese and nickel is 2: 1.

Doping a known alloy with vanadium in the range of 0.1–0.5 wt.% Enhances the dispersion of austenite decomposition products, and perlite acquires a sorbitol form, which largely stabilizes the carbide phase of the alloy and at the same time favorably affects the ductility of the proposed alloy. .

The introduction of boron, a strong degassing agent and a deoxidizing agent of the alloy effectively affects the complex refractory oxides of chromium, titanium and vanadium, increasing the flowability of the alloy. The addition of boron in the range of 0.005-0.05 wt.% Appears to be very influential for the formation of a solid solution of implantation and retention of the process: the transformations. Insoluble boron binds to nitrides and carbides and in this state does not affect the temperature of the onset of grain growth and hardenability, but significantly increases the plastic and viscous properties of the alloy, and the cracks sharply decrease during casting and heat treatment. details of complex configuration.

Calcium addition as a modifying element in the range of 0.03-0–15 wt.% Leads to a decrease in the degree of contamination of the alloy both by line inclusions of alumina, and oxides with oxygen and sulfides with sulfur, which are quite refractory (1800-2700 C} and float to the surface of the melt into a donkey, which, ultimately, has a positive effect on the increase in fluidity, plastic properties, 5a also increases the crack resistance of the alloy even when the metal is overheated.

Treatment of the liquid alloy with antimony in the range of 0.002-0.008 wt.% Together with such deoxidizing agents as silicon, aluminum, titanium, and calcium makes it possible to markedly increase casting properties.

50

5 Q 5

about 5

five

alloy due to a sharp decrease in contamination by both line inclusions and the elimination of intergranular inclusions (sulphides and oxides). This combination of deoxidation and micro alloying of the alloy provides for obtaining high plasticity and viscosity properties, as well as wear-resistant characteristics of the alloy due to the formation of new refractory compounds and their redistribution during heat treatment. Moreover, the ability of antimony to prevent the formation of additional phases, one of which is the formation of graphite, leads to inhibition of their growth, change in shape, reduction of the dispersion of pearlite and the thermodynamic activity of silicon, titanium and aluminum, contributing to the free precipitation of carbon in the form of graphite. These indicated factors stabilize the high mechanical characteristics of impact resistance and wear resistance.

The choice of the collateral content of manganese in the range of 1-5 wt.% Nickel in the range of 0.5-2.5 wt.% And silicon to 1.5-2p5 wt.% Is explained as follows.

Manganese actively suppresses the pearlite transformation of austenite of high-chromium alloys, while complete, inhibition of pearlite transformation is observed at 5 wt.%, And the amount of residual remains. precise austenite and its stability increase with increasing manganese content, which has a strong effect on mechanical characteristics. At the same time, manganese in combination with nickel in the proposed alloy stabilizes austenite so much and lowers the temperature of martensitic transformation, that the metal base is extremely austenitic, and i i TiTBHCHT and diffusion decay products do not form. Moreover, higher casting and technological properties are observed with an optimal ratio of manganese and nickel equal to 2: 1. This is explained by the fact that the complex rational alloying of the alloy with manganese and nickel at the indicated ratio leads to a maximum increase in the hardenability of the alloy, and a uniform distribution of the carbide composition. structure and austenitic matrix and has an almost pearlite-troostite structure.

five

Silicon within the specified limits has a positive effect on increasing the hardenability, and also provides stable impact-abrasive wear resistance.

An aluminum content of 0.05-0 May 15 and titanium 0.05-0.15 May L provides a reduction in the brittleness of the alloy due to a decrease in casting and thermal stresses in the castings and, as a result, a delay in the process of structural transformations.

The chosen ratio of manganese to nickel of 2: 1 is optimal for the proposed alloy, since these components in a ratio of more than 2 and less than 1 sharply reduce both the casting and technological and mechanical characteristics. This is due to the fact that at the specified ratio of manganese to nickel the maximum hardenability of the high-chromium alloy is ensured and suppresses pearlite transformation in cross-sections up to 200 mm, and also contributes to the reduction of cracks or in the castings, especially when casting in metal chill molds. .

Example. The alloy is smelted in the ICT-6 induction furnace.

The chemical composition of the proposed alloy and known are given in table. The foundry, technological and mechanical characteristics of the proposed alloy and known - in table. 2

The crack resistance of specimens in the form of grinding cylinders with a diameter of 25 mm and a length of 38 mm from the proposed alloy and the known are tested during their casting on a conveyor-chill machine, using surface shower-water cooling for 1 minute.

The impact-abrasive wear tests are performed by the same grinding cylinders from the proposed alloy and known in the centrifugal-throwing machine with the rotation of the drum at 550 rpm and the presence of the raw abrasive mixture to obtain clinker and a duration of 20 minutes.

Impact testing of grinding cylinders from the proposed

19746

The alloy and the famous MK IIM3-14 are carried out on a tiller copre, with a dynamic strike of a striker of 14 kgm.

5As can be seen from the table. 2, samples from

The proposed alloy with the specified range of doping and a rational ratio of manganese and nickel equal to 2. 1 S have higher properties of plasticity and high corrosion resistance, while maintaining a high level of impact-abrasive wear resistance. When the content of alloying additives below the lower limit to the proposed

5, the chemical composition and the upper limit of the observed deterioration of the complex properties.

Thus, the proposed alloy possesses high foundry, technological and mechanical characteristics in comparison with the known wear resistant alloy, and can be used in industry for wear parts, which are operated under the conditions of dynamic loads and abrasive wear.

Claims (1)

Invention Formula U Wear-resistant alloy containing carbon, silicon, manganese, chromium, vanadium, aluminum, nickel, calcium, titanium and iron, characterized in that, in order to increase ductility and crack resistance while maintaining the level of impact-abrasive wear resistance, it additionally contains boron and antimony in the following ratio of components, wt.%: 0 Carbon 2.8-3.8 Silicon 1.5-2.5 Manganese 1-5 Chromium 8-12 Vanadium 0.1-0.5 5 Aluminum 0.05-0 , 15 Nickel 0.5-2.5 Calcium 0.03-0.15 Titanium 0.05-0.15 Boron 0.005-0.050 0 Antimony 0.005-0.050 Iron The balance of manganese and nickel is 2: 1, t a 6 l and c a I Rest 0.005 0.03 0.05 - Table2