Investigation of Effect of Heat Treatment on the Han Dynasty Steel Sword Corrosion by Electrochemical Corrosion Testing

Abstract

Different quenching treatments with two heating temperatures (820 °C and 940 °C) were carried out in several quenching medium (mineral water, vinegar, and pig grease) on modern Chinese swords to simulate the ancient quenching process prevalent during the Han dynasty. The electrochemical corrosion behavior of these swords in the soil from the Han dynasty buried layer were measured in an attempt to discern the method of heat treatment of an ancient steel sword found in the same layer of earth. The results show that the corrosion resistance of the test swords in the soil increased with decreasing quenching temperature. Furthermore, the sword heated at 820 °C and quenched with mineral water showed the lowest corrosion rate in the Han dynasty buried soil. However, the sample heated at 940 °C and quenched with mineral water showed the most similar electrochemical behavior to the ancient sword. Therefore, we speculate that the ancient sword was also heat treated in this manner