Abstract
This investigation is carried out to clarify the factors influencing the weldability of beryllium-copper alloy, using the 25-alloy and 10-alloy. 25-alloy is copper-base alloy containing 1.80-2.00% Be, more than 0.20% (Co+Ni) and less than 0.6% (Co+Ni+Fe). And 10-alloy is also copper-base alloy containing 0.4-0.7%Be and 2.35-2.70% (Co+Ni).
From the Auger analysis of the fracture surface of weld, it is supposed that the poor weldability of this alloy is due to formation of beryllium oxide on the weld interface. The results obtained as follows.
(1) Difference of weldability between several heat treated alloys is not noticeable.
(2) Weldability of 10-alloy is superior to that of 25-alloy. This is supporsed to be due to the difference of beryllium quantity segregating on the weld interface.
(3) Weldability in high vacuum is superior to that in air.
(4) Copper and nickel plating are expected to be very effective to improve the weldability of berylliumcopper alloy, because of establishment of intimate contact of weld interface, reduction of beryllium quantity on the weld interface, and its rpotection action from oxidation of that.
