Oscilation : applicable to Machine/Automatic welding system where welding is being carried with programed movement of welding torch i.e. you can pre set movement in x, direction ,also movement distance of torch/arc and this is fixed once welding starts viz, from right to left or vice versa
While as weaving during welding is generally for manual welding and this is being controlled by welder it depends upon the position ,Weld joint configuration etc and this is variable and weld properties depends upon weaving size , particularly Impact properties
Regards
Hegde