This　study　investigates　the　mechanism　behind　the　dual-stagnation　points　flow　phenomenon　in　the　keyhole　plasma　arc　welding　(KPAW)　melt　pool　and　develops　a　corresponding　control　strategy.　Positional　information　on　flow　stagnation　points　was　obtained　using　the　macroscopic　morphology　of　the　melt　pool　and　liquid　flow　velocity　measurements.　The　position　of　these　stagnation　points,　determined　by　the　directional　flow　of　liquid　metal,　is　crucial　for　characterizing　the　stability　of　the　welding　process.　The　study　delves　into　the　driving　force　mechanism　that　produces　stable　directional　flow　and　a　uniform　temperature　distribution　within　the　melt　pool.　A　significant　discovery　of　this　research　is　the　identification　of　high-speed　directional　material　transport　channels　within　the　melt　pool.　Furthermore,　a　correlation　mechanism　between　the　positions　of　stagnation　points　and　the　stable　flow　with　temperature　distribution　has　been　constructed.　To　address　the　unstable　and　destabilization　stages　of　the　welding　process,　a　dynamic　material　stability　transfer　control　strategy　was　designed,　based　on　liquid　flow　velocity　and　temperature　distribution.　This　strategy　ensures　a　smooth　transition　during　the　unstable　stage　and　rapid　self-healing　of　the　melt　pool　during　destabilization.　This　study　provides　a　novel　control　strategy　and　a　theoretical　foundation　for　the　automation　and　enhancement　of　the　KPAW　welding　process,　highlighting　its　necessity　in　advancing　welding　technology.