Common problems with die-casting parts

The die-casting part is not formed and the cavity is not fully filled

Reason for occurrence: 1. The temperature of the die-casting mold is too low; 2. Low temperature of molten metal; 3. The pressure of the press is too low; 4. Insufficient liquid metal; The injection speed is too high; 5. The air cannot be expelled.

Adjustment method: 1-2. Increase the temperature of the die-casting mold and molten metal; 3. Replace the high-pressure die-casting machine; 4. Add enough molten metal, reduce the injection speed, and increase the thickness of the feed inlet.

Design specifications

The design of die-casting parts must consider seven aspects: the wall thickness of the die-casting part, the casting fillet and demolding slope of the die-casting part, the reinforcement ribs, the minimum distance between the casting holes and the edges of the die-casting part, the rectangular holes and grooves on the die-casting part, the inserts inside the die-casting part, and the machining allowance of the die-casting part.

Design Specification for Casting Rounds

Usually, there should be rounded corners at the intersection of various parts of die-casting parts (except for the parting surface), which can make the metal flow smoothly during filling, make it easier for gas to be discharged, and avoid cracks caused by sharp angles. For die-casting parts that require electroplating and coating, the rounded corners can be evenly coated to prevent paint accumulation at sharp corners. The fillet radius R of die castings should generally not be less than 1mm, with a minimum fillet radius of 0.5mm.

Design Specification for Embedded Components in Die Casting Parts

Firstly, the number of inserts on the die-casting parts should not be too large; Secondly, the connection between the insert and the die casting must be firm, and it is required to have slots, protrusions, and rolling patterns on the insert; Again, the insert must avoid sharp corners to facilitate placement and prevent stress concentration in the casting. If there is severe electrochemical corrosion between the casting and the insert, the surface of the insert needs to be coated for protection; Finally, castings with embedded parts should avoid heat treatment to prevent volume changes caused by phase transitions between the two metals, which can loosen the embedded parts.