Preparation method of metallographic sample of cast iron oxidizing layer

Abstract

The invention discloses a preparation method of a metallographic sample of a cast iron oxidizing layer, comprising the steps: (1) manually cutting a sample; (2) grinding the abrasive surface of the sample; (3) embedding the sample; (4) grinding the abrasive surface of the embedded sample; (5) manually polishing the abrasive surface of the embedded sample: (6) manually polishing the abrasive surface of the embedded sample by sequentially utilizing a plurality of pieces of waterproof abrasive paper from thick to thin, and rotating the embedded sample by 90 DEG in the same direction as changing the abrasive paper once; and (7) polishing the abrasive surface of the embedded sample. In the steps, the embedded sample needs to be always ground in a single direction from the oxidizing layer to be tested to the cast iron layer on the abrasive surface. The preparation method prevents the metal tissue of the cast iron layer from disturbing the oxidizing layer to be tested and is easy to align to a grinding direction and convenient for operation.

Description

technical field [0001] The invention relates to the technical field of metallographic sample preparation, in particular to a method for preparing a metallographic sample of an oxide layer of cast iron. Background technique [0002] When detecting the thickness of the metal oxide layer, the thickness of the oxide layer can be detected by making a metallographic sample of the metal oxide layer. The existing metallographic sample preparation process generally involves rough grinding, fine grinding, polishing, corrosion, etc. Several professional processes are used to make metallographic samples. The metallographic samples can be observed under a microscope to measure the thickness of the oxide layer on the metal. Because the size and shape of the obtained metal rough samples are often not suitable for grinding or polishing, Before grinding, it is generally necessary to inlay the rough metal sample by an inlay machine in order to meet the subsequent sample preparation steps. Th...

AI Technical Summary

Problems solved by technology

The oxide layer of cast iron exists on the surface of the cast iron. In order to ensure the detection accuracy, the crude metal sample needs to be taken directly from the workpiece. The cast iron oxide layer is easy to peel off when it is worn, and the structure is easy to change when heated. The existing conventional metallographic Neither the sample preparation method nor the standard has formulated a targeted preparation method for the characteristics of the cast iron oxide layer. Therefore, the following problems often occur in the preparation of the existing metallographic samples of the cast iron oxide layer: 1. It is difficult to find the correct method during the preparation process Detection surface, 2. The oxide layer is easily damaged and peeled off during sampling, grinding, and polishing. 3. The oxide layer is easily heated to cause tissue changes. 4. The inlay material is easy to melt and contain the contaminated oxide layer during grinding or polishing.

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