Method for determining structure of cobalt phase in WC-Co cemented carbide

Abstract

The invention discloses a method for determining the structure of a cobalt phase in WC-Co cemented carbide. The method comprises the following steps: polishing the test surface of a WC-Co cemented carbide sample, electrolyzing for removing WC crystal grains on the surface layer of the sample, cleaning the surface of the sample, and testing the structure, the crystal size and / or the interplanar crystal spacing of the cobalt phase in the WC-Co cemented carbide through XRD. The method is characterized in that an electrolysis process is used to remove the WC crystal grains on the surface layer of the WC-Co cemented carbide sample, and the XRD analysis of the surface of the sample is carried out, so the influence of the WC phase on the surface layer of the sample is eliminated in order to obtain a complete cobalt phase diffraction pattern, thereby the phase structure, the crystal size and the interplanar crystal spacing of the cobalt phase can be accurately determined, and the method has the characteristics of simple technology and reliability.

Description

technical field [0001] The invention relates to the technical field of hard alloy material manufacture, in particular to a method for measuring the cobalt phase structure in WC-Co hard alloy. Background technique [0002] The cobalt phase of WC-Co cemented carbide has two structures: face-centered cubic (fcc) and hexagonal close-packed (hcp). The cobalt phases of these two structures have different physical and mechanical properties, such as fcc-Co than hcp–Co The toughness is better, so in the production of WC-Co cemented carbide, it is hoped that the cobalt phase of the cemented carbide has a higher fcc / hcp ratio, which requires the determination of the cobalt phase structure in the WC-Co cemented carbide. [0003] X-ray diffraction analysis (XRD) method is a traditional method to determine the cobalt phase structure in WC-Co cemented carbide. With the development of electron microscopy technology, electron backscatter diffraction (EBSD) technology has become a new method...

AI Technical Summary

Problems solved by technology

When using XRD to directly measure the cobalt phase structure in WC-Co cemented carbide, the XRD diffraction peak intensity of the WC phase far exceeds that of the cobalt phase, and the spectral lines of the cobalt phase are easily covered by the WC phase, making it difficult to accurately determine The structure of the cobalt phase

[0004] EBSD analysis has very high requirements on the flatness of the sample surface, and in WC-Co cemented carbide, there is a big difference between the cobalt phase and the WC phase in terms of hardness, wear resistance, and corrosion resistance, making it difficult to obtain a completely flat surface. s surface

Compared with XRD analysis, the sample preparation cost of EBSD method is high

In addition, in the conventional WC-Co cemented carbide, the thickness of the cobalt phase is very small, and the EBSD analysis is more difficult

[0005] Due to the interference of the WC phase diffraction peak, when XRD is used to directly measure the WC-Co cemented carbide surface or polished surface, the cobalt phase diffraction peak is very weak, it is difficult to obtain the correct fcc / hcp ratio, and it cannot correctly guide the production

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