Suggestions on the Use of Ceramic Foam Filters for Casting

 Ceramic foam filter for casting is a kind of porous material, which has a three-dimensional network structure and high porosity characteristics. Its function is to make the disorderly and churning molten metal liquid become stable, uniform and clean after passing the foam ceramic honeycomb hole, thereby greatly reducing the casting reject rate caused by non-metallic inclusions and other casting defects, and saving production costs.

 

The ceramic foam filter is made of polyurethane foam as the carrier and is immersed in the slurry made of ceramic powder, binder, sintering agent and suspending agent, etc. Then the excess slurry is squeezed out so that the ceramic slurry is evenly applied to the framework of the carrier to form the green body, and then the body is dried and sintered at high temperature. This process is also known as organic foam impregnation and is a relatively mature production technology in China.

 

Recommendations for the use of foam ceramic filters:

 

(1) According to the alloy melting point to choose the appropriate material filter, in order to avoid too high temperature, damaging the filter function that can not achieve filtration effect.

 

(2) The purification effect should match with the casting requirements by selecting the corresponding mesh.

 

(3) The upper limit of casting temperature should be adopted as far as possible in order to increase mental fluidity.

 

(4) When the filter screen is placed horizontally under the cross cup or on the parting surface, the casting height shall not exceed 20cm. It is better to flush the liquid metal on the wall of the intersecting cup instead of directly rushing to the filter screen.

 

(5) The filter must be handled with care. When not in use, it should be placed in a dry and ventilated place to avoid moisture absorption affecting the strength of the filter.