Global Casting News

Announcements on Normalizing Process for Steel Investment Castings


Normalizing is the normally used heat treating process for steel investment castings. After normalizing, the steel investment castings are with better mechanical properties. 

To control the steel investment castings with a good mechanical property, there're several announcements on normalizing. 

1.Position of fixing the steel investment castings

During normalizing treatment, the steel investment castings should be fixed in certain position. They can't be located randomly. A good position during normalizing can make areas of steel investment castings heat treated homogeneously. 

2.Normalizing for steel investment castings with different sizes

*For steel investment castings with long shape or thin diameter, it's much better to place them well to avoid distortion defects.

*If steel investment castings with small section surface and big section surface are heating in same oven. The castings with small section should be placed at front of the oven. 

*For complex steel investment castings, especially for those with hollow shapes, it's much better to preheat the castings, then, increase the temperature slowly. This will help to avoid stress defects left in steel investment castings caused by quick heating process.

3.Steel investment castings cooling after normalizing

After normalizing, the steel investment castings should be placed separately on dry ground. Heated castings can't be overlapped, or
placed in moist ground. These will affect the cooling on different sections of the steel investment castings. The cooling rates on different sections will affect the hardness at those areas.

4.Normalizing for steel investment castings with different materials

If the required temperatures for steel investment castings with different materials are same, they can be heat treated in one oven.

5.Heating temperature of normalizing for steel investment castings

Generally, temperature of water can't higher than 40℃. Temperature of oil is less than 80℃.