JPS60221169A - Filter medium for molten metal - Google Patents

Abstract

PURPOSE:To improve a casting material by filtering a molten metal with a carbon fiber fabric coated with refractories. CONSTITUTION:Alumina or heat-resistant paint is thermally sprayed or coated onto a commercially marketed plain weave fabric made of carbon fiber to about 25mu thickness. The molten metal of a cast iron, cast steel, etc. is filtered by the refractory-coated carbon fiber fabric obtd. by such method and is cast to form a casting. Since the filtration precision of the molten metal is improved in this stage, the tensile strength of the completed casting is improved by about 10%. The improvement in the quality of the casting is thus made possible when the index for deciding the superiority of the casting quality is considered in terms of the strength of the casting.

Description

[Detailed Description of the Invention] Today, when producing cast iron, cast steel, stainless steel, etc., a porcelain strainer (or screen) is installed in the runner of the mold to remove inclusions in the molten metal. There are cases. However, the strainers manufactured so far have large hole diameters of 3 to 5 mm and have poor filtration accuracy, so they have not contributed much to the improvement of material quality.

The present invention has been made in view of such circumstances.

In other words, the purpose is to coat a carbon fiber cloth with excellent heat resistance with a refractory material, use it to filter molten metal, remove inclusions in the molten metal, and produce healthier castings. be.

Since it is difficult to measure the amount of inclusions removed, in this experiment we judged the quality of the cast based on its strength.

This will be explained below using examples.

Example Commercially available carbon fiber plain woven fabric (thickness: 0.25, mesh gap i
The molten metal was filtered using alumina (1.5 x 1.5 mg) sprayed to a thickness of about 25N and a heat-resistant paint coated to a thickness of about 25P.

The test results are shown in the table below.

The above values are the average values of 5 test pieces.

That is, the tensile strength of cast iron (Fe12) is 22.1 kg7-
When filtered through carbon fibers coated with alumina according to the present invention, the concentration was 24.2 kg/ml, and when filtered through carbon fibers coated with heat-resistant paint, the concentration was 24.0 kg/ml. When cast steel (SC42) with a tensile strength of 42.7"9/- is filtered through the alumina-sprayed carbon fiber of the present invention, the tensile strength is 46.
5 kg/ztA, and when filtered through carbon fiber coated with heat-resistant paint, it was 46.3 kg/mt. In addition, when stainless steel (SC8I2) with a tensile strength of 49.7 kfl, - is filtered through carbon fiber sprayed with alumina, the tensile strength is 54.7.
kg/rut, and when filtered through carbon fiber coated with heat-resistant paint, it becomes 54.8 kg/1n1N, and it was found that the strength was improved by about 10% in each case.

As described above, we believe that the filtration material for molten metal of the present invention greatly contributes to the soundness of castings.

Claims (1)

[Claims] A filtration material for molten metal, characterized in that a carbon fiber cloth is coated with a refractory material, and the molten metal is filtered using the refractory material.