How To Check the Quality of Die Castings? Part I

Die casting is not strange for us, it is widely used in many industries, but some of professional knowledge of die casting process, such as its features, quality inspections still need our deep study, so as to have a better understanding on die casting.

 

Here we will have a detailed introduction.

 

The die casting definition:

Die casting process is a part of pressure casting. Pressure casting machine is used to inject the liquid metal such as copper, zinc, aluminum or aluminum alloy of metal into the feedstock gate. Then a solid metal diecast part comes out with the mould shape. By definition, we can know that the pressure die casting can make all kinds of intricate shapes, and it also has a higher precision and a good level of clarity, which saves electricity, raw metal material, and the casting part has a smaller weight and a higher machinability. Die-casting process is widely used in automobile, internal combustion engine production, motorcycle manufacturing, motor manufacturing, oil pump, transmission machinery, precision instruments, garden beautification, electric power construction, building decoration and other industries.

 

In general, the quality check of die casting part has these following aspects:

1. Dimension test: including the line detection method and the three coordinate detection method.

2. Mechanical properties detection: including tensile, hardness, impact, fatigue and other properties.

3. Chemical composition detection: chemical analysis or spectral analysis is used to check the chemical composition of the die casting alloy.

 

For the surface quality defects of die castings, there are two inspection methods:

1. Visual inspection:

General visual inspection is done in the sunlight or lamplight, basically to see whether die casting surfaces have defects including porosity, shrinkage, depression, bubble forming, cold insulation, bad, crack, etc.. In special circumstances 5 to 10 times magnifying glass is used to inspect for better results.

 

2. Stain test:

A method commonly used to check the surface defects of diecast parts. It is a nondestructive testing method used to detect small discontinuities. The specific operation is to infiltrate the coloring agent into the defect of the die casting surface, remove the excess penetrant, and then apply the phasing agent to the casting, and the developer will stain. And we can determine the location, size, and shape of the defect from the shape of the color change.

 

In addition to the above, there are also other aspects to fully check the quality of die castings, Sieg-Huao is a professional China advance die casting supplier and manufacturer, we will explain to you other considerations in another article: How To Check the Quality of Die Castings? Part II.