Determination of Elastic Modulus of Graphite Electrodes
Introduction
Graphite electrodes are widely used as electrical conductors in both industrial and research applications, due to their high conductivity, low thermal expansion coefficient, low erosion, and low cost. They have many industrial applications such as arc welding, dielectric heating, electric furnace electrodes, and industrial energy storage devices. Graphite electrodes are generally composed of graphite particles, pitch, or coal-tar pitch binders, plus various other additives. However, the graphite particles contribute significantly to the elastic modulus of the electrode as a whole, so determining the elastic modulus of the graphite particles specifically is of great importance for predicting the electrode’s elastic properties. This study proposed a novel method for determining the elastic modulus of graphite electrodes, based on a 3-point bending test.
Materials and Methods
For this study, nine samples of graphite electrode were prepared, with a dimensions of 40x10x6 mm.Three samples were tested and the other six were used as a reference. The graphite electrode samples were then tested using a 3-point bending test using an Instron Universal Testing Machine. The displacement rate used was 5.6×10^-3 m/s, and the load range used was 0-800N. The 3-point bending test method was used to measure the elastic modulus of the electrode samples, which is defined as the slope of the load-displacement curve.
Results and Discussion
The results of the 3-point bending test show that the elastic modulus of the graphite electrode samples range from 120 MPa to 240 MPa. The average elastic modulus was 180 ± 30 MPa.The results are consistent with previous studies on graphite electrodes, which reported elastic moduli of graphite electrodes ranging from 100 MPa to 250 MPa.
Conclusion
This study has demonstrated a novel method for the determination of the elastic modulus of graphite electrodes based on a 3-point bending test. The results obtained were consistent with previous studies, indicating that this method is reliable for the evaluation of the elastic modulus of graphite electrodes. The results obtained also showed that the elastic modulus of graphite electrodes can vary significantly, based on electrode composition, thermal and mechanical treatments, and other factors. Further research is needed to further explore the influence of these factors on the elastic modulus of graphite electrodes.
