Analysis of possible problems in the process of aluminum alloy die casting

1. Geometric defects: the shape and size of the die casting deviate from the technical requirements; the size is out of tolerance, deflection, deformation, etc.

Surface defects: The appearance of the pressed poems is poor, with patterns, flow marks, cold partitions, shift points, lack of meat, burrs, sink marks, strains, etc.

Internal defects: pores, shrinkage cavities, shrinkage porosity, cracks, inclusions, etc., the internal structure and mechanical properties do not meet the requirements.

2. Influencing factors

(1) Caused by the die-casting machine: the performance of the die-casting machine, whether the energy provided can meet the required injection conditions: whether the injection force, injection speed, and clamping force are sufficient. Whether the selection and regulation of die-casting process parameters are appropriate, including pressure, speed, time, punch stroke, etc.

(2) Caused by die-casting molds

Mold design: mold structure, gating system size and location, ejector pin and layout, cooling system.

Mold processing: mold surface roughness, machining accuracy, hardness.

Mold use: temperature control, surface cleaning, maintenance.

(3) Caused by the design of die castings

Die casting wall thickness, corner position, draft angle, hot joint position, deep concave position, etc.

(4) Caused by die casting operation

Alloy pouring temperature, smelting temperature, coating amount and operation, production cycle, etc.

(5) Caused by alloy material

The composition, cleanliness, ratio, smelting process, etc. of raw materials and returned materials. Incorrectness of any of the above factors may lead to defects.