We reveal the interaction of H with He in pure W and W-Ta alloy based on first-principles calculations. We show a strong attraction between H and He in both systems that drives H segregation towards He. The substitutional He and tetrahedral interstitial H defects in W-Ta alloy are more energetically favorable than pure W due to the decreased electronic density of the replaced Ta atom. Moreover, 1 He-Vac complex in both systems can trap as many as 12 H atoms. Based on the calculated formation energy of H_n-He-Vac complexes, the H₃-He-Vac has the lowest formation energy in both systems. We believe that such understanding is generally applicable for H bubble formation in metals and metal alloys.

基于第一性原理计算，我们揭示了纯W和W-Ta合金中H与He的相互作用。在这两个将H偏向He的系统中，H和He之间都显示出强大的吸引力。由于被取代的Ta原子的电子密度降低，W-Ta合金中的He和四面体间隙H缺陷置换比纯W在能量上更有利。此外，两个系统中的1 He-Vac络合物可捕获多达12个H原子。基于H _n -He-Vac络合物的计算形成能，H ₃ -He-Vac在两个系统中具有最低的形成能。我们认为，这种理解通常适用于金属和金属合金中的H气泡形成。