Home / News

Laser cutting machine processing quality evaluation standard

There is no uniform standard for the quality evaluation of laser cutting in the world. So far, there is no standard for laser cutting quality in our country. The main basis for testing the quality of laser cutting is JIS and WES (welding specifications). In CEN (European Standardization Agency) and ISO (International Standardization Agency) there are questions about the standardization of laser cutting. The relevant ISO9000 series quality assurance methods mainly provided by EU have conducted research on laser cutting standards and standard sample regulations, etc.


ts contents include: cutting quality grade division, setting the standards of samples and processing samples, optical system, model of price samples and beam characteristics, etc.



For laser cutting processing, evaluating its processing quality mainly includes the following principles:


1. Smooth cutting, no streaks, and no brittle fracture;


2. The slit width is narrow, which is mainly related to the diameter of the laser beam spot;


3. The cutting seam has good verticality and small heat-affected zone;


4. No material burning, no molten layer formation, no large slag;


5. The surface roughness of the incision, the size of the surface roughness is the key to measure the surface quality of laser cutting.


In addition to the above-mentioned principles, the state and final shape of the molten layer during processing directly affect the above-mentioned processing quality evaluation indicators.


The surface roughness of laser cutting mainly depends on the following three aspects:


1. The inherent parameters of the cutting system, such as spot mode, focal length, etc.;


2. Adjustable process parameters during the cutting process, such as power size, cutting speed, auxiliary gas type and pressure, etc.;


3. The physical parameters of the processed material, such as the absorption rate of the laser, the melting point, the viscosity coefficient of the molten metal oxide, the surface tension of the metal oxide, etc. In addition, the thickness of the processed part also has a great influence on the surface quality of laser cutting. In contrast, the smaller the thickness of the metal workpiece, the higher the cut surface roughness level.



To obtain a better surface quality level, the process parameters such as laser power and cutting speed must be optimized many times. Generally speaking, for materials with the same characteristics and thickness, there is a set of optimal cutting process parameters, which will also result in different cut surface quality. Metal materials have low melting point, high thermal conductivity, low melt viscosity, and low surface tension of metal oxides. It is easy to obtain high surface quality during laser cutting machine. When laser cutting flat plates, it is easy to measure the surface quality, but when performing fine processing or cutting some complex patterns, it is difficult to directly measure it. The surface quality can only be controlled by optimizing test parameters. Therefore, in order to facilitate automatic cutting, the corresponding relationship between the external optimization parameters and the surface quality level should be established.