Stained Castings
Defects
Stained or discolored castings
Cause
Contamination of the molten metal with foreign substances, most commonly die lubricant but potentially other materials as well.
Corrections
-
Evaluate lubricant usage practices:
- Verify plunger lubricant quantity: Ensure the proper amount of plunger lubricant is being used.
- Assess application consistency: Maintain consistent application of lubricant to prevent excessive buildup.
- Check die lubricant quantity: Verify that the appropriate amount of die lubricant is being used.
- Review lubricant mixture ratio: Ensure the correct mixture ratio of lubricant components is being employed.
- Consider alternative lubricant materials: Explore the use of different lubricant options that may minimize staining issues.
-
Inspect liquid metal for foreign material:
- Identify potential contamination sources: Investigate potential sources of foreign material, such as scrap metal.
- Implement filtration systems: Implement effective filtration systems to remove impurities from the molten metal.
- Maintain proper melting and pouring practices: Follow recommended melting and pouring techniques to minimize contamination risks.
Staining from die lubrication (0.5X).
Please note that the information provided in this article is intended to be a general guide to the causes and corrections of stained castings in metal castings. However, it is important to note that the specific cause and correction of any particular defect will vary depending on the specific casting process, alloy, and other factors. Therefore, it is important to consult with an experienced and professional engineer to ensure that the correct diagnosis is made and the most suitable correction is chosen.