According to these parts from comics, when Thor's hammer hits Captain America's shield a flash of light would appear. The Vibranium of the shield absorbs the impact and convert it into light. This is called sonoluminescence.
Can Thor break Captain America's shield? If Thor is armed solely with Mjölnir, then as shown in the various Avengers movies since the original in 2012, he cannot destroy Cap's Shield.
Energy can't be destroyed, just transformed from one form to another. And if you take the energy of Thor's hammer striking Captain America's shield, there's a large amount of kinetic energy in the hammer that is transferred to vibrational energy in the shield.
If the Russo Brothers' thoughts are correct, Cap was really just showing humility and spared Thor's ego by not fully lifting the hammer. This ultimately leads to Thor saying “I knew it!” upon seeing Captain America wield the hammer in Endgame.
As per a theory shared by Screenrant, the answer might be two-fold – 1) Captain America is a super-soldier, and 2) he possesses the strength of Thor (hence he's able to hold Mjolnir).
When his conversation with Captain America's shade was over, the God of Thunder flew into space and waited till the exact minute of Rogers' death. At that moment, he used Mjolnir to release a powerful electromagnetic pulse that shut down all communications systems across the entire globe.
How Can Captain America Lift Thor's Hammer? Simple: Steve Rogers is worthy. The inscription on Mjolnir reads “Whosoever holds this hammer, if they be worthy, shall possess the power of Thor.” It doesn't matter how strong you are, if you aren't worthy, you can't lift Thor's hammer, no matter how hard you try.
Other than Thor and Odin, certain other individuals have proven worthy of lifting Mjolnir in the primary continuity: Roger "Red" Norvell (a deliberate ruse by Odin) Beta Ray Bill. Buri (also known as Tiwaz, Thor's great-grandfather)
Thor, the god of Thunder, was undoubtedly the most powerful member of the original Avengers. His power continues to grow in the Marvel Cinematic Universe.
1 Captain America (Steve Rogers)
Many fans viewed this as an unsuccessful attempt to lift Mjølnir. However, Marvel Studios president Kevin Feige revealed in an AMA (via Reddit) that Steve was actually "always worthy" and was just being polite.
Throughout Marvel Comics, the Hulk has tried and failed to break Captain America's shield but has never even come close, and since Superman is only a little bit stronger than the Hulk in his base form, it makes sense that Superman wouldn't be able to break the shield either.
The fact that Thanos possesses enough power to beak vibranium is a testament to the strength of the Mad Titan, but more importantly, the weapon itself. Although the origin of the sword is unknown, the evident force and qualities of the blade reveal clues to its composition.
Thanos' Sword Is Made From Uru
Uru is a special metal in the Marvel universe that is said to only be created in the core of dying stars, making it ultra rare and incredibly strong. In fact, Thor's Mjolnir is made of the Uru metal making it comparable to Thanos's sword in terms of strength.
Thor is repeatedly vanquished by the 5 new Phoenix hosts over the course of 12 issues: Colossus, Namor, Cyclops, Magik, and Emma Frost. Colossus even manages to knock Mjolnir out of Thor's hands at one point, demonstrating the strength of Phoenix and why it should not be trifled with.
Captain America may well be one of the greatest fighters in the Marvel Universe, but even years of combat experience and an unbreakable shield can't match Thor when it comes to sheer power.
People of Asgard are inherently more powerful than humans, and the God of Thunder experienced extreme growth throughout the movies. His abilities evolved over time, much like Captain America's, but because of his godly background, Thor has a slight advantage over his human teammate.
2) Captain Marvel
She holds her own with Thanos in hand-to-hand combat for longer than Thor, Iron Man, or Steve Rogers, and takes down his enormous warship single-handedly.
DC & Marvel's Crossover Universe Made Hulk the Weakest Avenger - IMDb. The Hulk has been called the strongest Avenger given his unparalleled, planet-shattering strength, but within the 2099 future of Marvel and DC's crossover universe, the Hulk would be considered the weakest Avenger (for one specific reason).
And Mathaudhu can cite documentary sources to back him up. For example, Marvel – which publishes the Thor comics – issued a “Thor's Hammer” trading card in 1991 that states Mjolnir is made of Uru and weighs precisely 42.3 pounds. That's lighter than a herd of 300 billion mice, much less a herd of 300 billion elephants.
Yes, even Spider-Man has been worthy of holding the hammer of Thor. This is not your father's Spider-Man (well, actually, it could be if your dad was a kid in 1993), but instead is the Spider-Man of Marvel's distant future of 2099!
Black Widow star Scarlett Johansson has confirmed that she has no plans to return to the Marvel Cinematic Universe in the future.
Without question, the One Above All is the most powerful character in all of Marvel Comics. How do we know this? Well, the One Above All is literally God. The creator of every single being in existence, the One Above All is the ultimate force for good in all the multiverses.
Hence, Mjolnir determines worthiness based on Odin's definition of worthiness. However, since Mjolnir also has a conscious being within it, in the form of God Tempest, another likely explanation is that it is God Tempest that determines the worthiness.