Re-manufacturing method for direct laser cladding of failed carburized quenching piece

Abstract

The invention discloses a re-manufacturing method for direct laser cladding of a failed carburized quenching piece. The method comprises the following specific steps that (1), surface treatment is carried out, specifically, surface treatment is performed on the surface of a base body of the failed carburized quenching piece, so that the surface is kept clean and is free of an oxide layer; (2), laser cladding is carried out, specifically, according to a matrix material, a cladding material is selected, a cladding device is selected, process parameters during cladding are set, and laser claddingre-manufacturing repair is carried out on the surface of the treated failed carburized quenching piece; and (3), inspection is carried out, specifically, crack detection and hardness detection are carried out on the carburized quenching piece. When the laser cladding is carried out in the step (2), the used re-manufacturing repair material is a powder material and has a particle size of 150 meshes to 270 meshes; and the repair material comprises the following components of, in percentage by mass, 0.1 wt.%-0.17 wt.% of C, 15 wt.%-18.5 wt.% of Cr, 0.3 wt.%-1.00 wt.% of Mn, 1.0 wt.% -1.5 wt.% ofSi, 1.2 wt.%-2.0 wt.% of Mo, 0.8 wt.%-1.50 wt.% of B, 1.2 wt.%-2.0 wt.% of Ni, and the balance Fe. According to the re-manufacturing method, laser cladding can be carried out without removing a carburized layer, a cladding layer is free of cracks, the forming process is good, and meanwhile, the cladding layer has excellent wear resistance.

Description

technical field [0001] The invention belongs to the field of remanufacturing of mechanical products in material processing, relates to a remanufacturing method of direct laser cladding of carburized and quenched parts, and is applied to remanufacturing in the field of metallurgical industry. Background technique [0002] Carbon is the main element that determines the properties of steel. Generally speaking, the higher the carbon content of the steel, the higher the strength and hardness of the steel, and the better the wear resistance of the steel. For this reason, the surface of steel structure functional parts serving under severe working conditions such as heavy loads and impacts generally needs to be carburized and quenched to achieve the purpose of core toughness and surface hardness, and meet the requirements of use. However, the increase of carbon content will also increase the cold brittleness and aging tendency of steel. Therefore, the welding of carburized and qu...

AI Technical Summary

Problems solved by technology

However, due to the following characteristics of carburized and quenched parts: 1. After the workpiece is carburized, the surface is quenched, so the carbon content of the carburized layer is very high (>0.8%), and the hardness of the carburized layer after quenching is very high (HRC58-62) ; 2. Carburized and quenched parts cannot be subjected to conventional preheating during remanufacturing and repair (over 200°C, the hardness of the carburized layer will decrease); 3. The hardness of the repaired layer should be equivalent to that of the carburized layer, that is, the repaired layer must also have high hardness

Due to the constraints of the above three conditions, direct laser cladding (surfacing) on ​​the carburized layer will lead to cracking of the substrate and repair layer

Therefore, the current laser cladding basically needs to remove the carburized layer before laser cladding. The disadvantages of this method are: 1. The process is complicated and the cost is high; 2. The removal of the carburized layer destroys the overall performance of the workpiece. The performance of the workpiece after cladding is much worse than the original performance; 3. Since the carburized layer must be removed as a whole, this laser cladding method cannot achieve partial repair of the workpiece

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