Method for preparing multiphase ceramic coating by self-reaction electric arc spraying

Abstract

The invention discloses a method for preparing a multiphase ceramic coating by in-situ reaction synthesis, characterized by: selecting a proper metal skin material to prepare cored wires, wherein a reactive drug core of self-propagating high-temperature synthesis (SHS) system is coated by the metal skin material; using electric arc spraying equipment to conduct self-reaction electric arc spraying, in the spraying process, igniting the highly exothermic SHS reaction by electric arc, rapidly generating a target ceramic phase while using arc energy and heat release of the SHS reaction to obtain a high temperature ceramic melt, and spreading the high temperature ceramic melt on the surface of a metal matrix by using high pressure atomizing gas, and using the characteristic of rapid solidification of the high temperature ceramic melt to obtain the high performance multiphase ceramic coating with a micro-nano crystal structure. The invention has the advantages of simple equipment, low cost and wide applicability, and can be applied for surface strengthening and protection of components which suffer wearing, corrosion and high temperature environment in military and civil industrial equipment.

Description

technical field [0001] The invention relates to a reaction synthesis preparation technology of a multiphase ceramic coating, which is particularly suitable for the preparation of a wear-resistant protective coating on the surface of metal parts. Background technique [0002] Arc spraying technology is one of the lowest cost and most suitable for large-scale promotion in thermal spraying technology. However, the principle of arc spraying determines that it can only be used to spray conductive low-melting-point metal wires at first, and it is difficult to directly obtain high-performance ceramic coatings with high melting point, high hardness, high wear resistance, and non-conductive properties. In the late 1970s, the appearance of powder core wire brought vitality to arc spraying technology. Compared with solid core wire, arc sprayed powder core wire has the advantages of both outer skin and inner core materials, which not only overcomes the difficulty of drawing wires with ...

AI Technical Summary

Problems solved by technology

[0003] However, at present, arc sprayed ceramic coatings are mostly prepared by directly filling the powder core wire with sprayed ceramic materials. During the spraying process, there are prominent problems such as difficulty in completely melting the ceramic material, uneven distribution of ceramic phases, and weak bonding between coating layers. , so that the performance of the coating is seriously affected; or a small amount of reactive components are added to the metal or alloy, and the ceramic phase is synthesized by reaction during the spraying process to obtain a hard phase particle-reinforced metal-based composite coating to improve the coating’s durability. However, due to the small content of ceramic phase, the overall performance of the coating, especially the high temperature wear resistance, is still not comparable to that of ceramic-based composite coatings with ceramics as the main body.