RU2381884C1 - Composition of powdered material for inductive welding - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention can be used during welding of machine components, allowing large wear surfaces, operating in the mode of intensive abrasive wear, load impacts and high contact stress, particularly of drive wheels and supporting rollers of caterpillar mover. Powdered material contains components in following ratio, wt %: ferrochrome 20-30; carbon 1.7-1.9; chrome 14-16; silicon 0.9-1.0; powder "ПГ-СР-2-М" 2.8-3.2; manganese 7.7-8.8; reinforcing component 3.0-5.5; borax 0.9-1.1; boric acid 9.9-12.1; soda ash 0.9-1.1; calcium hydroxide 0.9 - 1.1; silicocalcium 1.8-2.2; welding flux 4.5-5.5; iron - the rest. In the capacity of reinforcing component there are used abrasive particles, received after smooth finish by wear-proof abrasive disks, for instance el'bor borazon material, fused alumina, silicon carbide, boron nitride, monocrystalline alumina and others. There can be used different powdered materials of mineral product, such as granite, basalt. Dispersion of hardening particles is not more than 1 mm.

EFFECT: invention provides increasing of speed and quality of welding, and also abrasive wear resistance of applied by inductive methods coats ensured by optimal combination of components.

3 cl, 3 ex

Description

The invention relates to the field of welding materials, and in particular to the composition of powder mixtures for induction methods for surfacing hard alloys.

Known mixture for induction surfacing of powder materials, containing, wt.%: Hard alloy - 78-82; boric acid - 9.9-12.1; soda ash - 0.9-1.1; calcium hydroxide - 0.9-1.1; silicocalcium - 1.8-2.2; welding flux - 4.5-5.5 [1].

The disadvantage of this composition of the charge for induction surfacing is the insufficient quality of the coating and the low speed of surfacing when changing the composition of the carbide component of the charge.

A higher quality of the resulting coatings provides a composition containing carbon ferrochrome in granules with a particle size of 0.6-1.2 mm in the following ratio of components, wt.%: Carbon 1.7-1.9, chromium 14-16, nickel 2, 8-3.2, silicon 0.9-1.0, manganese 7.7-8.8, ferrochrome 20-30, iron - the rest [2].

The disadvantage of this composition is its low wear resistance when working in conditions of intense abrasive wear.

The aim of the invention is to increase the speed and quality of surfacing, as well as abrasive wear resistance applied by induction methods of coatings.

The stated goal is achieved through the use of powder material for the induction surfacing of carbide coatings containing carbon, chromium, nickel, silicon, manganese, ferrochrome and iron, DISTINCTIVE in that it additionally contains boric acid, soda ash, calcium hydroxide, silicocalcium, welding flux and sodium tetraborate, as a hardening component, contains either abrasive material obtained after grinding surfaces with diamond and other wear-resistant (elbor, electrocorundum, silicon carbide, boron nitride, monocorundum) with grinding wheels, or powder materials of mineral origin (granite and / or basalt particles), and instead of pure nickel, PG-SR-2M nickel-based powder material was used in the following ratio, wt.%:

1. ferrochrome 20-30 2. carbon 1.7-1.9 3. chrome 14-16 4. silicon 0.9-1.0 5. PG-SR-2-M 2.8-3.2 6. manganese 7.7-8.8 7. abrasive material grinding wheels 3.0-5.5 8. sodium tetraborate 0.9-1.1 9. boric acid 9.9-12.1 10. soda ash 0.9-1.1 11. calcium hydroxide 0.9-1.1 12. silicocalcium 1.8-2.2 13. welding flux AN-348A 4,5-5,5 14. iron rest

At the same time, materials used in the production of abrasive grinding wheels (elbor, electrocorundum, silicon carbide, boron nitride, monocorundum, etc.) with a particle size of not more than 1 mm or powder materials of mineral origin (granite, basalt) with particle size not more than 1 mm.

The varieties of hardening component proposed above can be used as part of any surfacing mixtures for induction surfacing.

The surfacing process is as follows. Powder material is prepared in the indicated proportions. The resulting composition is dried, calibrated on a sieve with a diameter of up to 1.2 mm and mixed thoroughly. A predetermined layer of the developed powder material is applied to the product and melted by a flat inductor. Then, after cooling the coating, a mechanical cleaning of the deposited coatings is carried out with wear-resistant grinding wheels.

An example of using the invention

Prepared III version of the composition of the powder material in the following ratios of components, wt.%:

Option I.

1. ferrochrome 25.0 2. carbon 1,5 3. chrome 15.0 4. silicon 1,0 5. surfacing powder PG-SR-2-M 2.5 6. manganese 8.0 7. abrasive material grinding wheels 4.0 8. sodium tetraborate 1,0 9. boric acid 10.0 10. soda ash 1,0 11. calcium hydroxide 1,0 12. silicocalcium 2.0 13. welding flux AN-348A 5,0 14. iron rest

Option II.

The composition of the powder material according to option I, but used as a hardening component, wt.%:

7. granite powder particles 4.0.

Option III.

The composition of the powder material according to option I, but used as a hardening component, wt.% ::

7. basalt powder particles 4.0.

On the induction installation of type VCHG-9, coatings were deposited onto rectangular samples made of steel 45 (hardness HB 250), the resulting coatings were cleaned and hardness measured and metallographic analysis.

Microstructural studies of all the obtained coatings deposited by induction methods revealed the following. A carbide coating 1.5 ... 2.0 mm thick with inclusions of a reinforcing component of artificial or mineral origin is formed on the surface of the workpiece. The substrate structure of 8 ... 10 mm consists of troostomartensite, sorbitol extends to a depth of about 10 mm, and then the ferrite-pearlite structure of the main material of the part is observed.

The applied coatings have a hardness of up to 70 HRC, while individual inclusions (particles of an abrasive wheel, granite or basalt) have a hardness of up to 11-12 GPA. The change in the structure of the substrate is caused by thermal influence on it during the coating process. As a result, hardening of the base material to HRC 35..42 in the troostomartensite zone and to HRC 25 ... 30 in the sorbitol zone is noted.

The invention improves the speed and quality of surfacing, as well as the abrasion resistance of coatings applied by induction methods due to the optimal combination of components of the developed new powder material and can be used for surfacing of machine parts, such as drive wheels and track rollers of a caterpillar mover having large wear surfaces and working in the mode of intensive abrasive wear, shock loads and high contact stresses.

Tribotechnical studies of the wear rate on an AE-5 friction machine according to the end-friction scheme of three finger samples with coatings applied by an induction method from three different powder material variants revealed an increase in their wear resistance by 10 or more times due to the resulting coating structure and the presence of a strengthening component.

Information sources

1. RF patent №2147980. The mixture for induction surfacing.

2. RF patent No. 2206438. Composition for induction surfacing.

Claims (3)

1. A powder material for induction surfacing of carbide coatings containing carbon, chromium, nickel, silicon, manganese, ferrochrome and iron, characterized in that it additionally contains boric acid, soda ash, calcium hydroxide, silicocalcium, welding flux, sodium tetraborate and hardening component in the form of abrasive particles obtained after grinding by wear-resistant grinding wheels, or in the form of particles of granite and / or basalt, and nickel is introduced in the form of a powder on a nickel base PG-SR-2M, in the following ratio SRI powder material, wt.%:
ferrochrome 20-30 carbon 1.7-1.9 chromium 14-16 silicon 0.9-1.0 PG-SR-2M powder 2.8-3.2 manganese 7.7-8.8 hardening component 3.0-5.5 sodium tetraborate 0.9-1.1 boric acid 9.9-12.1 soda ash 0.9-1.1 calcium hydroxide 0.9-1.1 silicocalcium 1.8-2.2 welding flux 4,5-5,5 iron rest 2. The material according to claim 1, characterized in that as abrasive particles of grinding wheels it contains particles of diamond, or elbor, or electrocorundum, or silicon carbide, or boron nitride, or monocorund. 3. The material according to claim 1 or 2, characterized in that the particles of the reinforcing component have a dispersion of not more than 1 mm