Metal Sand Casting Introduction

The process mentioned in this article is sand casting, which is a casting process in which molten liquid metal is formed in a sand mold. Steel, iron, and most non-ferrous alloy castings can be obtained by sand casting. Because the molding materials used in sand casting are cheap and easy to obtain, and the molds are easy to manufacture, they are suitable for single-piece production and small batch production of castings. For a long time, it has been the basic process in metal casting production.

Process cost: mold cost (low), single piece cost (medium)

Typical products: metal fixtures for buildings, vehicle parts, furniture, lamps, engines, etc.

Suitable output: suitable for single piece and small batch production

Quality: low precision of the formed surface, but suitable for casting hollow and porous parts

Speed: Moderate single piece cycle (5min-30min), depending on the proficiency of the operator

Applicable materials

1. Sand casting is suitable for ferrous metals and non-ferrous alloys, the most commonly used materials are: iron, steel, copper alloy, aluminum alloy.

2. Magnesium has also been increasingly used in sand casting in recent years, especially in the aerospace field.

Design considerations

1. The draft angle should be controlled between 1°-5° (2° is usually more appropriate)

2. The wall thickness of the parts should be controlled between 2.5mm-130mm (1in-5.12in)

3. Different metals have different cooling shrinkage rates. For example, for parts with the same volume, the shrinkage rate of steel is almost twice that of aluminum and iron, and the shrinkage rate of brass is 50% higher than that of aluminum. The shrinkage is proportional to the volume of the part.