A kind of preparation method of iron-boron compound coating

Abstract

The invention discloses a preparation method for an iron-boron compound coating. An electrospark deposition process is adopted for preparation, and a used electrode is of a round-rod-shaped partially-hollow structure. An electrode material is a single phase Fe2B material, or a material composed of Fe2B and Fe3B, or a material composed of FeB and Fe2B. A prepared iron-boron compound in the coating obtained after electrospark deposition is conducted is Fe2B and Fe3B, or FeB and Fe2B or FeB, Fe2B and Fe3B, and furthermore, the coating contains a martensite phase with the weight fraction being smaller than 8%. Compared with a boriding process, the preparation method is easy to implement and environmentally friendly, and the prepared coating has the beneficial effects of being high in hardness, toughness, better in wear resistance and the like.

Description

technical field [0001] The invention relates to a method for preparing a surface coating, in particular to a method for preparing an iron-boron compound coating, which can be used to strengthen, modify, repair and remanufacture the surface of metal parts and tools and molds, and can significantly improve their performance. Surface wear resistance and corrosion resistance and other properties. Background technique [0002] Surface engineering technology can prepare a coating or coating on the surface of a material that is different from the base material and has special properties such as light, electricity, magnetism, heat, wear resistance, and corrosion resistance. It changes the material in the most economical and effective way. The morphology, chemical composition and organizational structure of the surface and near-surface regions have realized the strengthening, modification, repair and remanufacturing of the material surface. This technology has been widely used in ac...

AI Technical Summary

Problems solved by technology

However, due to the limitations of the boronizing process itself, at present, boronizing has encountered many unavoidable problems in actual production: (1) The high temperature of boronizing damages the properties of the substrate, which is easy to cause grain growth and deformation of the workpiece; (2) High energy consumption, a lot of waste, difficult to handle, pollute the environment, and cumbersome process; (3) Not suitable for effective boronizing treatment of large-sized workpieces or parts of workpieces; (4) Boronizing substrates have Selectivity, high silicon steel is not suitable for boronizing, easy to form soft belt; high speed steel is not suitable for boronizing, high quenching temperature Fe 2 B eutectic point; (5) generally coarse structure, preferred orientation, no equiaxed crystals; (6) workpiece needs re-heat treatment after boronizing

However, the current electrodes used for EDM are all solid round rod electrodes. After a period of time, the deposition end of this type of electrode will gradually become sharper. When the tip of the electrode deposition end is in point contact with the workpiece, the line of the electrode tip will The speed will be infinitely close to zero. At this time, it is very easy to cause discharge instability, form large oxidation black spots, and seriously deteriorate the performance of the coating.

At present, the method to solve the above problems is to cut off the tip of the electrode with tools such as pliers when the electrode is about to become sharp, but this process is cumbersome, especially for mechanically automated EDM, this method is very inconvenient to apply