1. Hard white oxide is a surface treatment technology, which can improve the wear resistance, corrosion resistance and surface hardness of materials by forming a dense and high-hardness oxide layer on their surfaces.

2. Generally, the whole surface treatment process needs to be carried out again, including removing the original oxide layer, cleaning the surface of the material and carrying out new oxidation treatment. These steps may affect the performance of the material, and may not guarantee good bonding and uniformity between the repair layer and the original layer.