Study On The Welding Wire Used In Repairing ZL205A Alloy Castings

ZL205A alloy is favored more and more by the designers of military, aviation and spaceflight industry because of excellent mechanical properties. The castings are made of ZL205A alloy, however, often have many defects for its bad casting capability, which have to be repaired with welding. But the repairing areas mostly appear hot-crack defects which are not eliminated easily. In fact, the influencing factors of welding hot-crack defects include welding technique and welding wire, the latter is more important because the hot-bearing sensitivity of welding wire is a decisive actor.Study on weld repair of ZL205A alloy casting has hardly been reported by now. The filled metal commonly is made of base-material, which either is cut into bar from base casting directly or is made into bar or curled welding wire. The quality of the welding area is welded by this kind of filled metal is not satisfying, so it is urgent to develop a new type of welding wire to resolve this problem. Taking the research way of wrought aluminium alloy as reference, this paper do a lot of research in optimizing the chemical composition of ZL205A alloy and modifying with additions to improve the hot bearing sensitivity of the welding wire and so lower the probability of the hot-crack defects in welding repair areas of ZL205A alloy castings.The results of orthogonal test about alloy compositions such as Cu, V, Zr testified that it barely could lower the hot bearing sensitivity of ZL205A alloy only adjusting the chemical compositions, which is opposite to some document reports. The reasons may be ZL205A alloy...