Defects in Heat Treatment Of 304L Stainless Steel Strip

304L stainless steel strip is a popular variety in the steel strip Market. In recent months, its market price is relatively stable, and many friends also take advantage of this opportunity to purchase in large quantities. When processing the steel strip, heat treatment is a very common treatment process. It can improve the processing performance of the steel strip and eliminate internal stress. However, there are defects in heat treatment. Today, we focus on heat treatment defects.

The defects of heat treatment of 304L stainless steel strip are mainly reflected in the following aspects:

1. Due to gas corrosion, irregular black dot shaped pits will appear on the surface of the steel strip. Especially in the process of heat treatment, the surface of the steel strip remains emulsion, oil and other dirt, which will lead to gas corrosion on some or even all of the surface of the steel strip, especially at high temperature.

2. Overheating, if the heat treatment temperature is too high, the surface of the steel strip will show dark brown. During subsequent treatment, even if the oxide scale on the surface has peeled off, it is not easy to clean the acid pickling. When the heating temperature of the steel strip is too high or the steel strip stays in the furnace for too long, it will lead to intergranular corrosion.

3. Under heating: during heat treatment, if the temperature is too high, it will affect the treatment effect of the steel strip. Similarly, if the temperature is too low, it will also affect the treatment effect of the steel strip. Under the condition of under heating, the surface of strip steel will show light gray metallic luster, which is because it is difficult to wash off the iron oxide scale during pickling. The main cause of under heating is that the heating temperature is too low or the time of steel strip in the furnace is too short.

4. There are black dot like pits on the surface of the steel strip, especially after pickling, which may be caused by the wear of the roller surface during heat treatment. In order to avoid this situation, the rollers in the furnace need to be replaced regularly.

It can be seen that there are still many defects in heat treatment of 304L stainless steel, but it does not mean that these defects can not be solved. As long as the process of heat treatment is strictly controlled, the defects can be greatly reduced.