Technology and key points of vacuum brazing diamond tools

I. Vacuum Brazing Process for Diamond Tools

1.Surface treatment of diamond substrate. Clean the surface of the diamond substrate to remove impurities, oxides, etc.
2.Prepare brazing materials. Select appropriate brazing filler (such as rhenium, molybdenum, etc.) and filling material (such as copper, silver, etc.).
3.Assembly of braze joint. Assemble the diamond substrate and braze joint components as required and place in a vacuum furnace for heat treatment.
4.Vacuum treatment. Place the assembled braze joint into the vacuum furnace and evacuate gases with a vacuum pump. Begin heating once a certain vacuum level is reached.
5.Brazing process. Determine the brazing temperature and pressure based on the selected brazing filler and filling material, then carry out brazing.
6.Cooling after brazing. After brazing is complete, allow to cool before removal.

II. Key Points of Vacuum Brazing Diamond Tools

1.Avoid oxidation and carburization effects. During brazing, avoid oxidation and carburization effects on the diamond. Therefore, before heating the diamond and braze joint in the vacuum furnace, evacuate gases to reduce the possibility of oxidation and carburization.
2.Suitable brazing temperature and pressure. Determine the appropriate brazing temperature and pressure based on the selected brazing filler and filling material. Generally, the diamond brazing temperature is between 1100°C and 1500°C.
3.Selection of rhenium brazing filler. Rhenium is a rare earth metal with good brazing performance, so it is commonly used as a brazing filler for diamond.
4.Selection of filling material. The filling material should be selected based on the actual situation. Typically, highly conductive metals like copper and silver are chosen as filling materials.
5.Quality inspection and control after brazing. After brazing, quality inspection and control of the brazed area should be performed. Common quality inspection methods include fracture observation and metallographic analysis.

III. Quality Inspection and Control Methods for Brazed Diamond

1.Fracture observation method. Break the brazed joint and observe the fracture surface. The bonding between diamond and brazing material, as well as whether the diamond substrate surface is melted, can be judged by observing the fracture surface.
2.Metallographic analysis method. Prepare a sample of the brazed piece and conduct metallographic analysis. Observe the bonding between diamond and brazing material as well as whether the diamond substrate surface is melted under a microscope.
3.Mechanical property testing. Test the strength, hardness and other mechanical properties of the brazed joint.