Conductivity measurement for checking the purity of copper

The challenges related to measuring the conductivity in copper

Pure copper is an essential material for a wide range of applications, from wire mesh for electric shielding to electrical components. Its purity needs to be verified before being used, since the required performance of the final product can never be achieved with inferior quality. Copper being a costly resource, wrong delivery can result in significant financial losses for both the producers and users. Therefore, it is critical to have a reliable and efficient solution for testing the purity of copper.

In this article, we will explore the benefits of the eddy current-based SIGMATEST solution using conductivity measurement for testing the purity of copper. 

Commonly used solutions 

The two most common solutions for testing the purity of copper are conductivity meters and spectrometers. While both solutions are effective in determining the electrical conductivity of copper, they each have limitations when it comes to accuracy and efficiency. 

Conductivity meters measure the electrical conductivity of a material, and since pure copper has a high electrical conductivity, it can be used to determine the purity of copper. However, the measurement accuracy can be affected by factors such as temperature, which requires a trained operator to use the instrument.

Spectrometers measure the composition of a material by analyzing its atomic emission spectrum. While they can detect impurities in copper, these are expensive and require a very skilled operator to use them.

Application Solution: Eddy Current-based SIGMATEST 

The eddy current-based SIGMATEST provides a more reliable and efficient solution for testing the purity of copper. With this method, a certain conductivity value of around 58 MS/m is expected for pure copper, and there is a defined electrical conductivity for copper alloys used in electrical components. 

Benefits of the SIGMATEST Solution 

1. High Measurement Accuracy, Especially for Copper

   The SIGMATEST solution has a high measurement accuracy, especially for copper, as it measures at an accuracy of 0.7 %. The eddy current-based method is nearly not affected by surface roughness or corroded surfaces.
   
   

2. High-Frequency Measurement (960 kHz) for Measuring Thin Materials

   The SIGMATEST solution can measure thin materials accurately due to its high-frequency measurement (960 kHz). This feature makes it ideal for measuring thin copper sheets used in electrical components and wire mesh. For example, copper with an electrical conductivity of 58 MS/m measured with a frequency of 960 kHz will allow an effective penetration depth of only about 0.07 mm.
   
   

3. Small Probe (Down to 3.5 mm) Available for Measuring Slim Flat Wires

   The SIGMATEST solution comes with a small probe that can measure slim flat wires down to 3.5 mm (about 0.14 in). This feature makes it easy to test the purity of copper wires used in electrical components and wire mesh.
   
   

4. Cost-Efficient Solution

   Compared to spectrometers, the SIGMATEST solution is more cost-efficient and requires minimal operator training. It is an affordable solution that can help save costs for both copper producers and users.
    

Conclusion 

In summary, the eddy current-based SIGMATEST solution provides a reliable, efficient, and cost-effective way of testing the purity of copper. It has a high measurement accuracy, especially for copper, and can measure thin materials accurately due to its high-frequency measurement. With a small probe for measuring slim flat wires, the SIGMATEST solution is ideal for testing the purity of copper used in electrical components and even wire mesh.