RU2270259C2 - Method of strengthening of components made out of medium carbon steel and high-carbon steels - Google Patents

Abstract

FIELD: mechanical engineering; welding production.

SUBSTANCE: the invention is pertaining to the field of mechanical engineering, in particular, to the welding production, mainly to manufacture and repair of the executive devices of agricultural machines. The technical effect of the invention is the increased service life of the executive devices of agricultural machines due to improvement of their strength characteristics and a wear-resistance to an abrasive wear. At short-time action on a component of a high intensity current - up to 16 kA in the welding machine MT-1614, as a result of a high heating appear the structural alterations caused by formation of quenching structures. Therefore the strength of the contact patch i.e. the heat-affected zone becomes considerably higher, then the strength of the parent metal. New in the given method is that for strengthening and as a consequence of it for increasing the agricultural machines executive devices components wear-resistance to the abrasive wear was usage of the electric welder МТ-1614. As a result of application of this method there is no need in the further machining or buying the dear alloying materials.

EFFECT: the invention ensures an increased wear-resistance of the agricultural machines executive devices components to the abrasive wear due to usage of the electric welder МТ-1614.

Description

The invention relates to the field of welding production, in the particular case to the manufacture and repair of the working bodies of agricultural machines in order to increase their durability and wear resistance with abrasive wear.

There are several methods for hardening the wearing surfaces of the working bodies of agricultural machines, implements, and other details, in which in some cases surface surfacing is used with metals having increased strength properties [1], in others, high-temperature hardening is carried out.

As a prototype, a method of surfacing of wear-resistant coatings was chosen, in which wear-resistant material of higher density than the base metal of the part is used as a deposited material. Deposition is carried out along the reinforcement lines to the entire depth with the creation of compressive stresses during cooling [2]. Compressive stresses are created by cooling the deposited layer in air from the crystallization temperature to normal temperature. After surfacing, the machining of the deposited coating is performed to obtain the necessary roughness.

The disadvantage of this method is the strong thermal effect and additional energy consumption.

The technical result of the invention is to increase the durability of the working bodies of agricultural machines by improving their strength characteristics and wear resistance to abrasive wear.

The indicated technical result is achieved by the fact that during the short-term high-temperature effect of a large current on medium-carbon and high-carbon steel, structural changes occur due to the formation of quenching structures, while the heat-affected zone (contact spot) acquires a hardness significantly higher than the base metal. Contact spots are applied both along the lines of reinforcement (Fig. 1), at a distance that is determined by the zones of thermal influence, and in a checkerboard pattern (Fig. 2). Specially selected process temperature allows you to get a hardened surface of the part. This is achieved by using the MT-1614 electric welding machine, which produces currents up to 16 kA (or another brand of spot welding machines). Thus, the claimed method meets the criterion of "novelty."

In Fig.1 and Fig.2 presents plow shares after exposure to them electric welding machine MT-1614,

where 1 - contact spots along the lines of reinforcement,

2 - mounting holes.

The implementation of the claimed method is illustrated by the example of hardening of serial plowshares of a plow. The surface of the plow share is strengthened by electric welding reinforcement by applying contact spots with a diameter of 15 mm at a distance between them of 15 ... 20 mm. The spots were applied by an MT-1614 electric welding machine with a welding current of 16 kA.

Information sources

1. Batishchev A.N., Golubev I.G., Lyalyakin V.P. Recovery of agricultural machinery parts. - M .: Informgrotech 1995, 296 p.

2. Patent RU 2 184 639 C1, cl. B 23K 9/04, 2002

Claims (1)

The method of hardening parts of medium-carbon and high-carbon steels, including hardening by short-term high-temperature exposure to a current of 16 kA with the application of contact spots on the surface of the part in a checkerboard pattern or along reinforcement lines.

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