Direct-current pulsed arc processing system and arc processing method

Abstract

The invention relates to a direct-current pulsed arc processing system and an arc processing method, belonging to the surface technical field. The system comprises a basic parameter control module A, a man-machine parameter setting device B, a DSP (digital signal processor) controller D and a main circuit C, wherein the main circuit C comprises a rectifier Z1, an inverse circuit 1, a high-frequency transformer T and a rectification circuit 2 which are accessed into an alternating current circuit in turn; the output of the rectification circuit 2 is provided with a spraying wire 1 and a spraying wire 2; and a current signal sampling device LEM1 is connected between the rectification circuit 2 and the spraying wires. In the whole spraying process of arc processing, the output frequency of the wire feeding pulse and the gas feeding pulse of a gas flow valve 4 is consistent with the output frequency of power supply energy, thus the peak values and basic values are simultaneously achieved.By using the system and method, metal layers can be covered on various thin parent materials, and a generated deformation is small; and small-energy spraying can be carried out on plastic or other workpieces with low melting points.

Description

technical field [0001] The invention belongs to the field of surface technology, and is mainly applied to arc spraying processing. Specifically, it refers to an arc spraying system and its application method that are different from other fast AC and DC pulses with small flow and precise control. technical background [0002] With the development of the surface technology field, the arc spraying process has been widely used in various surface modification fields, and various production industries have also put forward higher requirements for the spraying process. In some surface processes, it is often necessary to spray a thin wear-resistant or anti-corrosion metal layer on different metal base materials, some need to spray process metal materials on non-metallic materials such as plastics, and some need to cover new functional materials on sheet metal ; In the traditional continuous spraying method, it is difficult to achieve the requirement of accurately controlling the sp...

AI Technical Summary

Problems solved by technology

In some surface processes, it is often necessary to spray a thin wear-resistant or anti-corrosion metal layer on different metal base materials, some need to spray process metal materials on non-metallic materials such as plastics, and some need to cover new functional materials on sheet metal ; In the traditional continuous spraying method, it is difficult to achieve the requirement of accurately controlling the spraying thickness, and in the traditional rapid spraying process, due to the problem of excessive heat output, it is easy to cause thermoplastic deformation of the base material, and even melt the base material to affect the workpiece. practical functions, all of which require us to examine the practicability of process technology methods from a new design perspective

To sum up, although the traditional high-energy and high-rate spraying technology is relatively mature, there are two basic problems: 1. During the spraying process, due to the high temperature of the sprayed particles, the processed workpiece is often overheated and deformed, and even serious Will destroy the performance of the original material

2 In some highly demanding ultra-precision spraying processes, the coating thickness is too large to meet the actual requirements

However, when the spraying current is reduced, the strong action of the spraying gas will take away a lot of heat, and the arc cannot provide enough energy, and the ionization degree of the arc space decreases, which will cause an arc break

In addition, the impact force of a large flow of gas may bend the shape of the arc, the arc length becomes longer, and the stability of the arc will also decrease.

If the spraying gas flow rate is reduced while the current is reduced, although the arc can be stabilized, due to insufficient particle speed, the bonding strength between the particles and the substrate surface cannot be guaranteed, and the coating quality cannot meet the requirements.

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