Preparation before Welding Tungsten Carbide and Steel(2)
a) It is necessary to inspect the grooves on the steel substrate whether reasonable or not ,especially for the cemented carbide grade which is easy to be cracked and big brazing surface ones ,more strictly inspection must be taken.The cutting groove has to be sand-blasted and clearance of oil dirt .If the work is large ,you can use the alkaline solution to boil them 10~15min .For the high frequency welding or copper-leaching welding for multi-edges or complex cutting tools,it is better to take borax solution to boil them 20~30min,and them to weld after dry out .
b) The brazing alloy has to be wiped off with alcohol or gasoline ,meanwhile to crop them as per the actual brazing surface .When braze common tungsten carbide cutting tools or moulds ,the brazing alloy thickness ranging from 0.4~0.5mm is reasonable ,its size similar to the brazing surface is ok.However ,if heating with coke furnace ,the brazing alloy could be increased appropriately .When braze cemented carbide multi-edges cutting tools ,and measuring tools, you should try to minimize brazing area .It is generally 1/2 of the brazing surface size ,if the brazing technique is very mature ,it is also ok to reduce the brazing alloy to 1/3 or less of the brazing surface .You can get more beautiful work-piece and make edge-grinding more easily by means of reducing of brazing alloy .
