Advantages and disadvantages of laser welded diamond circular saw blades

The earliest diamond saw blades used electroplating technology. In the middle and late 20th century, with the development of the world, people developed stone materials in the construction industry, and high-frequency welding technology appeared first. In 1990, with the advent of laser welding technology, the process and function of diamond circular saw blades were also fully developed. Compared with the early high-frequency welding process, what are the advantages of the laser welding process? This is the focus of this discussion.

1: Heat resistance.

High-frequency welding technology has been controversial since its inception. Simply put, the choice of solder has always been an issue affecting the development of high frequency welding. Although there are many types of solders on the market at present, most of the solders have a melting point between 600-850 degrees Celsius. When the temperature exceeds 700 degrees Celsius, diamond began to show obvious high temperature carbonization. In the welding process, the thermal stability of the diamond is directly affected. In other words, the diamond will easily fall off during the cutting process, which directly affects the cutting. But if the soldering temperature is kept low, the cost of solder, such as silver solder tabs, rises rapidly. With 18% silver content of the solder, the melting temperature of the solder piece should exceed 800 degrees Celsius; if 35% tin-silver solder piece is used, the temperature can be controlled at about 700 degrees Celsius, which has a low impact on diamond carbonization.

In general, during the welding process of diamond saw blades, if the temperature required by the solder is high, diamond carbonization will occur, resulting in unstable cutting of the saw blade. But if the solder has a lower soldering melting point, then the cost of the solder goes up.

The laser welding saw blade adopts the method of fusion of the diamond segment and the saw blade, so that the saw blade and the diamond segments are not combined with solder, which has little effect on the thermal stability of diamond segment. That is a major advantage of laser welding saw blades. The most obvious manifestation of this advantage is that laser-welded saw blades can be used for dry cutting.



2: Welding strength.

In the high frequency welding process, the connection between the saw blade base and the diamond segment is completely dependent on the intermediate welding layer. Since there is a relatively large gap between the two, and welding and the like also directly affect the welding strength. Then during the cutting process, the diamond segment will often fly out, fall, etc., which may lead to some safety accidents. Therefore, the welding strength is a very important point for people. It has been found that if higher solder strength solders are used, it is necessary to increase the soldering temperature, which is in conflict with the thermal resistance of the diamond segment. People have been trying to solve this problem for a long time, but there is currently no solution.

The laser saw blade uses a laser, and the welding point is irradiated by a laser beam to increase the temperature of the welding point to a state of deep welding. This temperature can make the base of the saw blade and part of the diamond segment directly into a gaseous state, and evaporation occurs. Finally, through the protection of inert gas, the welding area is rapidly cooled at room temperature, and a very small welding part is finally formed. Due to the fast and efficient welding method, the welding strength is very high.



3: The thermal stability effect of the solder layer.

In the high-frequency welding process, although the lower part of the diamond segment is welded, because the high-frequency welding cannot heat the individual welding layer, the thermal stability of the upper diamond segment is often affected, which will also have a certain impact on the structure of the upper diamond segments. Especially if the solder is not easy to melt, the higher soldering temperature will directly bring more uncertainty to the whole diamond segment.

The laser welding process only heats the welding part and has no effect on other welding layers, so the benefit is to provide a more stable saw blade.

Of course, there are also some problems with laser welding saw blades. For example, the base of the saw blade cannot be reused, because the saw teeth are damaged during the first welding. This also leads to the high price of laser welding machines, so they are not widely used.