The copper - zinc alloy filler metals are mainly adopted in the oxyfuel gas welding , high frequency welding , furnace welding , and used to braze the copper , copper alloy , steel , cast iron and hard alloy etc . Before brazing , you must clear away all dirt very well on the brazed place and on the surface of object to be brazed such as greasy dirt , oxide and so on . The best brazed joints space is between 0.025mm to 0.1mm .In order to get good braze , you need make up the right flux in the process of welding . The heat time should be shortest as possible and be avoided overheat so as not to the evaporation of zinc and the over -oxidation in the joint where will be formed the braze with many holes when these products are brazed in the oxyfuel gas welding . |  |