Firstly, let's take a look at the advantages of hard anodizing. The most significant advantage is that it can improve the surface hardness and wear resistance of the parts. The hard anodized layer has a high hardness of 60-70 Rockwell C, which is similar to that of hardened steel. This hardness can protect the parts from mechanical damage and wear, extending their lifespan. Moreover, hard anodizing can also enhance the corrosion resistance of aluminum parts. The oxide layer can prevent the metal from oxidizing, rusting, or reacting chemically with other substances.