Laser cladding method for strengthening surface of piercing point

Abstract

A laser cladding method for strengthening the surface of a piercing point includes the following steps of: (1) prefabricating WC / Co-base cladding powder; (2) pre-processing the surface of a piercing point workpiece, and cleaning up stain and rust; preheating for 2 to 5 hours at a temperature between 400 DEG C and 600 DEG C; (3) cladding the prefabricated composite powder fed in the way of reverse synchronization or coaxially in multiple steps by a CO2 laser; simultaneously, carrying out synchronous inert gas protection on the laser-cladding area; and (4) subsequent processing. The laser cladding method adopts laser to prepare a WC ceramic particle-strengthened Co-base composite coating on the surface of the piercing point, and the coating is metallically combined with the matrix, so the binding force between the coating and the matrix is enhanced; the maximum thickness of the coating can reach a few millimeters; and as the surfaces of WC particles are coated with Ni, the absorption of laser energy by the WC can be reduced, so that the burnout rate of the WC can be reduced in a laser melting pool. The distribution of the WC particles is uniform in the coating, the rigidity of the coating is high, consequently, the service performance of the piercing point can be improved, and the service life can be prolonged.

Description

Technical field [0001] The invention relates to the technical field of material surface strengthening, in particular to a laser cladding method for strengthening the surface of a perforated plug. Background technique [0002] The perforated plug is a key tool for the production of stainless steel, heat-resistant steel, bearing steel and other special alloy steel pipes. Its service life has a direct impact on the output, quality and production cost of the product. When the head is working, the temperature is about 1000℃, and it is exposed to huge axial pressure, radial pressure, rotational friction, and thermal stress from sudden cooling and heating. It is prone to nose collapse, deformation, and stickiness during use. Failure of steel and cracking. Therefore, it is required to have good wear resistance, high temperature oxidation resistance and chilling and heat resistance to meet the harsh production and use conditions. [0003] At present, a number of patents have been formed i...

AI Technical Summary

Problems solved by technology

However, the manufacturing needs to be carried out in a vacuum, the cost is high, and the bonding strength with the substrate is insufficient, especially the effective thickness of the coating is micron level, it is difficult to withstand the long working time of the plug, and harmful impurities will penetrate into the coating during use. Corrosion and damage, or partial tearing in the early stages of use

[0006] In summary, the existing perforated plug modification technology is still difficult to meet the needs of actual use in terms of preparation cost and performance. In production, there is an urgent need for a surface wear resistance and heat resistance much higher than that of iron-based alloys, which can work effectively. The layer is firmly combined with the substrate, has a certain size and thickness, and is a low-cost perforated plug preparation method

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