Dual metal joint interface metallographic etching agent and display method

Abstract

The invention discloses a dual metal joint interface metallographic etching agent and a display method. The dual metal joint interface metallographic etching agent comprises the following components: a first etchant which is a mixed solution prepared from 6-10% of H2O2 water solution and 27% of ammonia water according to the volume ratio of 1 to 1, a saturated aqueous solution with 0.5-1 ml of potassium dichromate, and a second etchant which is 4-6% of HNO3 anhydrous ethanol solution by volume. The method comprises the steps of: sampling, preparing a sample, preparing an etching reagent, and displaying and obtaining a metallographic structure map of the sample. The agent disclosed by the invention is easily prepared; a copper and copper alloy / steel dual metal composite material joint interface structure can be rapidly and clearly displayed; and test and analysis of related performances of the novel composite material can be accurately carried out. By adopting the dual metal joint interface metallographic etching agent, performance improvement and failure analysis inspection abilities of a dual metal composite material member can be improved; and the etching agent has important directive significance on production and use.

Description

technical field [0001] The invention belongs to the field of chemical analysis, and relates to a bimetallic joint interface metallographic structure corrosion reagent and a display method, in particular to a copper alloy / steel bimetallic joint interface metallographic structure corrosion reagent and a display method. technical background [0002] Bimetallic composite material is a new type of material that combines the advantages of physical, chemical, mechanical properties and price differences of two materials. In recent years, bimetallic composite materials have been rapidly developed and widely used in manufacturing and production. Metal composite materials such as copper-clad aluminum, copper-clad steel, and copper-plated steel have begun to be widely used. Some equipment manufacturers use bimetallic materials to replace the original single precious metal parts and components in order to reduce costs. The composite material parts of the equipment will have failure def...

AI Technical Summary

Problems solved by technology

In particular, the corrosion resistance of copper alloy / steel is quite different. Currently, the corrosive agents for single copper metal or acid solutions containing high-concentration nitric acid solution, ferric chloride hydrochloric acid solution, etc., are not effective for copper-based metal corrosion. At the same time, it will have different degrees of corrosion effects on the steel-based metal structure, or the strong oxidant reaction process is severe. When it is applied to the corrosion of bimetallic joints, it is difficult to control the corrosion process and effect, the success rate is low, and it is impossible to obtain clear boundaries. Joint metallographic structure

In addition, methods such as adding a syringe and controlling the flow direction of the reagent during corrosion also make the process complicated and difficult to operate, and it is impossible to guarantee a clear boundary structure. Therefore, the existing methods can no longer meet the needs of production and analysis.

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