Pretty sure it was channeling the power of the Bifrost when it was flying down on him (I think I remember seeing the telltale rainbow effect), which probably helped quite a bit.
This. It was a very powerful weapon anyway, one of the strongest in the universe and they were told it could manifest the bifrost. Thor got a massive power boost in Ragnarok, and was likely channeling his power into it, while it was deflecting the blast with the bifrost power, and Thanos just didn't think to hit him with the full power of the gauntlet. Until that point, one stone was more than enough to wreck anyone he had encountered.
Yeah. Also strongest material in universe taut can only be forged with the power of a star + bifrost power(which leaving it on for a bit can destroy a planet)and thor power all together hurled at extreme speed is a shitload of power.
And bifrost probably was warping the brunt of the blast away
Though Mjolnir is made of the same metal and Hela crushed it like a toy. ---
The Official Odin of the Shin Megami Tensei IV board. "You know how confusing the whole good-evil concept is for me."