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  • Causes and prevention measures of shrinkage of aluminum castings
  • Editor：Hangzhou Hongcheng Pml Precision Mechanism LtdDate：2017-06-13 15:10 Click：



aluminum casting manufacturer for the reasons for the shrinkage of aluminum castings and preventive measures:

The shrinkage of the aluminum castings usually occurs at the thick part of the riser’s root part, the thickness of the wall and the thin wall with large plane near the runner. In the cast state, the fracture is gray, and the light yellow after heat treatment is gray and pale yellow or gray black on the X-ray film, showing a severe filamentous Pinus, which can be found by X light and low fluorescence fractography.

shrinkage cause :

The difference of the 1. riser,

The 2. furnace has too much gas content

3. superheated

near the inner runner

There is too much water in the 4. sand mold and the sand core is not dried

Coarse grain

of 5. alloy

6. improper position of castings in the casting mold

7. pouring temperature is too high, pouring speed is too fast

prevention measures :

1. pouring liquid from riser and improving riser design

2. furnace material should be cleaned without corrosion

3. riser should be set at the shrinkage place of the casting, and cold iron or chill should be placed in conjunction with riser

.

4. control molding sand water, and sand core drying

5. measures to refine grain

6. improve casting position in casting mold, reduce pouring temperature and pouring speed