The strength of X65 is above 550Mpa. Then J557 welding rod, ER55 welding wire, argon arc welding, electrode welding, gas welding can be.
The strength of 20Cr and X65 is relatively high with slightly higher strength welding material. For example, the welding rod J557, the welding wire uses ER55-G. Proper preheating before welding can prevent welding cracks.
In general, the manganese steel of 65 is not strong with argon arc welding, and it can be welded by other Han general welding such as famine welding