Forging provides the best mechanical properties out of all manufacturing processes, but that doesn’t mean it’s faultless. Defects are common in forging, and most of them occur due to preventable errors or faulty processes. Let’s look at some of the most common types of forging defects and how you can prevent them in your foundry.
Unfilled Section
As the name implies, this defect is when sections of the product remain unfilled. It can occur for a few different reasons. Poor die design, improper technique, insufficient heating, and lack of raw material are the most common culprits. You can eliminate or reduce instances of this defect by improving the die design, ramping up the heat, and using more material.
Cold Shut
A cold shut defect is when small cracks appear at the corners of the workpiece. Its usual causes include poor die design, sharp corners, or excessive chilling of the workpiece. To avoid a cold shut, all you need to do is increase the fillet radius of the die.
Scale Pits
Scale pits are also some of the most common types of forging defects. They’re small cracks or holes in the metal that occur due to improper cleaning of forged surfaces.
Scale pits are a common defect in forging operations that occur in an open environment. To prevent them, take care to clean the surface thoroughly.
Die Shift
Die shift is when the upper and lower dies are incorrectly aligned. This defect causes improper workpiece dimensions.
The fix is simple—you just need to ensure the dies correctly align before you forge. To achieve proper alignment, place one half of the workpiece on the upper die and the other half on the lower die before pressing them together.
Flakes
Flakes occur when the workpiece cools too rapidly. This reduces the strength of the forged product and causes it to deteriorate. Slowly cooling the workpiece should keep it from flaking.
Surface Cracking
Surface cracking is another temperature-related defect. It occurs when the forging operation takes place at low temperatures, which causes the metal to crack. The solution is to work at a higher temperature.
Another way to prevent defects in your forging operations is to invest in forging automation. By automating your foundry, you can ensure forging conditions are optimal every time. Additionally, you can cut down on imperfections in your products. To learn more about automating your foundry, contact CSD today!
