Meltolit 9730 Metal paste
Copper-alloyed soft solder metal paste for copper, copper alloys, steel and stainless steel used mainly in HVAC and refrigerant industry but also for car body work Working temp: 250-350°C
3 layer sandwitch brazing alloy foil with 50% Ag, 2% Ni and with copper core. Used specifically for brazing tungsten carbides on steel. Saw blades, drill bits, tools etc.
The copper core works as a stabilizer against internal stress of the joint and will minimize cracks.