Temperature and time during segment welding of diamond saw blade

The welding process of diamond segment is actually the process of high temperature melting of the welding blade. First, we put the segment matching the saw blade base on the base teeth of the circular saw blade, and sandwich a layer of welding tabs between the saw blade and the base. It is a copper soldering piece or a silver soldering piece (silver content is more than 35 percent). After the melting point of the soldering piece is reached by fire or mechanical heating, the soldering piece melts and the segment is fixed straight to the teeth of the saw blade base. on. The quality of segment welding directly determines the service life of the segment. If the segment welding is not good, the segment will fall off directly; scratch the plate and so on. So what kind of segment is a welded segment? Simply put, the welding tool should be able to adjust the segment around and radially to ensure that the segment symmetry relative to the base body's end surface symmetry and circumferential symmetry meet the welding accuracy requirements.

Let me talk about the welding temperature and time control factors in the welding process with brazing tabs: For brazing tabs, because of the high melting point of copper, when the temperature is 900-950 degrees Celsius, the copper begins to melt, below 900 degrees Celsius , The brazing sheet is not completely melted, which will cause the welding to be weak, and even the brazing sheet is still solidified. At such a welding temperature, the segment will fall after a knock; if it is higher than 950 degrees, the brazing sheet will melt quickly, and Rapid oxidation produces copper trioxide and loses its ability to weld. As the temperature rises, the segment above the solder sheet will also undergo excessive carbonization of diamond due to excessive temperature, resulting in a decline in segment quality. At this temperature, 8-9 seconds is a relatively reasonable welding time. Through long-term welding tests, we found that the copper sheet did not melt sufficiently when it was less than 8 seconds, and more than 9 seconds, there would be a large amount of copper welding sheet. The air bubbles formed on the welding surface gap, resulting in weak welding.



Let's talk about the soldering problem of silver soldering pads. Before soldering, you must choose a suitable silver soldering pad with a silver content of not less than 35%. If it is less than 35 percent, the welding effect will not be achieved, but if the composition of silver is too high, it will cause the increase of welding costs, so generally the silver solder on the market generally maintains the silver content of 35%-45%. Because of the high price of silver soldering pads, the temperature and time must be strictly controlled during the soldering process, otherwise, once it fails, the soldering pads will be wasted. In terms of specific temperature control, the soldering temperature of the silver solder sheet is generally controlled between 600°C and 800°C. The higher the silver content, the lower the temperature requirement, and the higher the copper composition of the silver-copper solder sheet, the higher the soldering temperature will be due to the high melting point of copper. In terms of welding time, 6-7 seconds is the best to avoid problems such as excessive heating of each tooth or excessively high temperature welding, which will cause the induction area of each tooth to be too large and connect, which will cause abnormal deformation of the chip and cause the chip to be unusable. Of course, the power of the high-frequency welding machine must also be considered. Generally speaking, a machine with a power of 15KW can meet the demand. If a higher-power machine is used, the welding time can be appropriately reduced.



Whether it is a silver solder sheet or a copper solder sheet, the main purpose is to connect the diamond segments and the substrate well, fully melt and try not to overdo it, which is determined by the long-term experience of a good welding master.