During the final confrontation with an alternate Thanos, Captain America wielded the shield along with Mjølnir. Unfortunately, the shield was broken by Thanos' brute force with his Double-Edged Sword, leaving Captain America with a fractured shield.
Why did Captain America not have his shield in Infinity War?
Even in 2018's Avengers: Infinity War Captain America's shield is not seen, as Tony has taken the shield away from Cap aka Steve Rogers, feeling betrayed by him as the end product and consequence Civil War.
Rogers uses this to reconstruct the shield. During the 1991 miniseries The Infinity Gauntlet, Thanos, who possesses near-omnipotence via the Infinity Gauntlet, shatters the shield with a blow of his fist while in combat with Captain America.
Why did Captain America's shield break in Endgame?
Although vibranium is susceptible to damage, it's depicted as the most durable material in the Marvel Cinematic Universe. 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.
Steve Rogers lost his powers due to having the Super-Soldier Serum drained from him by the villain Iron Nail. This action aged Cap significantly. Steve called the Avengers together to tell them that Falcon would replace him as Captain America.
Captain America possesses no superpowers, though the Super-Soldier Serum has enhanced his body's strength, speed, agility, endurance, reflexes, reaction time, and natural self-healing ability to the peak of human physical perfection.
Thanos and Hulk have clashed several times in Marvel lore, with Thanos even admitting he was scared to face the Hulk before acquiring the Infinity Stones. While Thanos is usually the victor, it's generally down to him using superior tactics and technology, rather than simply possessing greater physical strength.
Then Thanos does the unthinkable; he uses his massive sword and starts slicing huge chunks out of Cap's supposedly invincible Vibranium shield. Say what? It turned out that Vibranium could be bested, apparently, by whatever the heck Thanos' sword was made from.
According to screenwriter Stephen McFeely, it's entirely possible that there are even stronger metals out there in the cosmos. "You can also see that while Vibranium is the strongest substance on Earth, whatever Thanos' straight razor there is made out of is stronger," he says on the commentary track.
In Marvel Comics, adamantium and vibranium weapons have gone toe-to-toe on several occasions, and the former usually comes out on top. However, in Marvel's live-action projects in the MCU and Fox's X-Men Universe, vibranium is clearly the stronger substance, and the more versatile.
According to the commentary track on the Endgame Blu-Ray, Thanos' sword comes from somewhere off-world, making it stronger than vibranium and quite a number of other things as well. Thor's weapons can't scratch them, for instance. Thanos' sword could thus be made of adamantium, which also seems unlikely.
Captain America's Shield is a vibranium shield that was extensively used by Steve Rogers. After the original shield was destroyed by Thanos during the Battle of Earth, Rogers traveled to an alternate timeline and acquired another shield, bestowing it to Sam Wilson.
More crucially, he says that his father King T'Chanda had gifted Howard Stark some Vibranium to help the war effort in the 1940s. In other words, Captain America's shield was made from Vibranium the secretive African nation freely gave to the Americans. Howard Stark: Your Highness, it's a pleasure.
They can cut through steel like butter. They have been shown to pierce Terrax, and damage Ultron, two highly durable & invulnerable characters (New Avengers v3#5 & Avengers v3#21); why not also Hulk? A vibranium weapon imbued with the power of the Wakandan gods. It's been shown to cut through anything.
Because without altering any continuities, if Fox's Wolverine and Marvel's Captain America were to come to blows, the claws would slice through the shield like a hot knife through butter. Vibranium can absorb kinetic energy, but it isn't indestructible (as evidenced by Thanos destroying the shield in Endgame).
Who would win in an MCU fight: Odin or Thanos? Without the Infinity Gauntlet, Thanos stands little chance against Prime Odin. Odin is stated to be able to shatter the Earth.
While the upgrades give Juggernaut the powers to kill Thanos with ease, it comes at the sacrifice of the former villain, as Juggernaut is abandoned after the Mad Titan is taken down, as no attempts are made to save him as he accelerates through space.
Exposure to so many enemies along with his trip through space may have weakened the Hulk to the point that he could bond with Bruce in Endgame, thus making the Professor persona appear much weaker. However, after snapping his fingers, the gamma burst should have raised his levels.
Summary. Captain America remains unwavering in his pursuit of truth, justice, and freedom, even at great personal cost. Steve Rogers' belief in doing the right thing may be his biggest weakness, leading to unforeseen consequences.
By far the most famous wielder of the hammer other than Thor was Chris Evans' Captain America, who lifted the hammer against Thanos in Avengers: Endgame.
Rogers suffered from asthma, scarlet fever, rheumatic fever, high blood pressure, and heart trouble, among other illnesses, and thus was frequently attacked by bullies on the streets. However, his resilience, despite his small stature, inspired Barnes to come to Rogers' aid and fight off the bullies when he was needed.
