IN718 alloy delta-phase corrosive liquid and preparation methods of corrosive liquid and sample

Abstract

The invention belongs to the field of preparation of corrosive liquids and samples and provides an IN718 alloy delta-phase corrosive liquid, a preparation method thereof and a preparation method of asample. A clear delta phase is conveniently and safely revealed, and the sample is prevented from being over-corroded. The IN718 alloy delta-phase corrosive liquid comprises the following ingredientsin ratio: 1.5g of anhydrous cupric sulfate powder, 20ml of absolute ethyl alcohol, 20ml of hydrochloric acid and 2ml of concentrated sulfuric acid. The preparation method of the corrosive liquid comprises the following steps: slowly and uniformly pouring anhydrous cupric sulfate powder into absolute ethyl alcohol, then adding hydrochloric acid and concentrated sulfuric acid and uniformly stirringand mixing with a glass rod, and standing until precipitates are completely dissolved, so that the IN718 alloy delta-phase corrosive liquid is obtained. The preparation method of the sample comprisesthe following steps: mounting, burnishing, polishing, and carrying out soaking corrosion, so that the IN718 alloy delta-phase sample is obtained.

Description

technical field [0001] The invention relates to a delta-phase corrosion solution, a method for preparing the corrosion solution and a sample, more specifically a preparation method for an IN718 alloy delta-phase corrosion solution, the corrosion solution and a sample. Background technique [0002] IN718 alloy is a precipitation-strengthened nickel-iron-based deformed superalloy. It has excellent thermal fatigue resistance, oxidation resistance, good durability and processing stability when used below 650 ° C. It is widely used in the manufacture of aero engines and industrial gas turbines. High-temperature hot-end components such as turbine disks. [0003] However, the high degree of alloying of IN718, coupled with the need for long-term service in a high temperature environment, leads to complex and changeable phase structures, especially the changes in the microscopic morphology and content of the δ phase seriously affect the macroscopic mechanical properties of IN718, so ...

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Problems solved by technology

[0003] However, the high degree of alloying of IN718, coupled with the need for long-term service in a high temperature environment, leads to complex and changeable phase structures, especially the changes in the microscopic morphology and content of the δ phase seriously affect the macroscopic mechanical properties of IN718, so appropriate alloys must be used. The phase sample preparation process corrodes a clear and effective δ phase morphology for subsequent analysis and evaluation

At present, electrolytic corrosion is carried out by using a three-acid corrosion solution with a volume fraction of 80% hydrochloric acid, 13% hydrofluoric acid, and 7% nitric acid, and a volume fraction of 30% hydrochloric acid, 35% nitric Hydrofluoric acid and 20% ethanol corrosion solution or H 2 o 2 The most common chemical corrosion is the corrosion solution with a volume ratio of 1:1 to HCL, but the tri-acid solution is extremely corrosive and volatile, which is likely to cause harm to the operator, and the use of electrolytic corrosion will undoubtedly increase the cost

In addition, the chemical corrosion time of the latter two corrosive solutions is extremely short, only 3-8s, which can easily cause severe over-corrosion, and even no clear and effective δ phase can be observed at all, which interferes with the analysis and judgment of the testing personnel.

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