- Halloween Marvel Thor Hammer : Target
- Thor's Hammer - Norse Mythology for Smart People
- Every Character Who Has Lifted Thor's Hammer - IGN
Black Uru Arm: After Malekith cut Thor's arm off, Odin had the Dwarves of Nidavellir forge a new arm for him. It was forged of Black Uru in the same furnaces where Mjolnir was forged, and took a thousand Dwarves to pound it into shape. 
Halloween Marvel Thor Hammer : Target
After a battle between Asgard and the Egyptian god of death, Seth, which resulted in Odin triumphantly returned to the throne of Asgard, Thor began to suffer sudden and momentary bouts of weakness during times of stress. Travelling within Thor’s mind, Doctor Stephen Strange the Sorcerer Supreme, discovered an evil version of Thor present, derived from Loki’s evil residue which had manifested when Thor, Loki, and Odin had mingled their essences to battle Surtur. Thor defeated his evil alternate version within himself.
Thor's Hammer - Norse Mythology for Smart People
Just one note before we begin: We're only counting cases where characters have lifted Mjolnir itself and not a copy, so that leaves out characters like Storm, Hercules, and Deadpool. And Odin was the one who had hammer made and designed its rules, so we're not including him, either.
Every Character Who Has Lifted Thor's Hammer - IGN
One metal that can withstand uru is more uru. When Thor’s hammer was used against some of his enemies on Asgard, set against him by Loki, those who had weapons made of uru were able to put up a fight. Uru, however, isn’t typically found in weapons when he makes his way to Earth.
Even though Loki couldn't remember his past acts and had become a child completely, the Asgardians still hated and despised him, bullying him mercilessly and even attempted to kill him. The only one who protected him was Thor, telling his brother that things would get better and that trust would come along with affection. As a result, Loki came to idolize and deeply love his older brother, doing all he could to help him and trying to become a better person than he was in his previous life. 
Once a worthy individual has become the one to hold the power of Thor, Mjolnir recognizes them as master and never wants to be separated for long. The hammer’s will to be with its master is so strong that nothing can stop it from returning to them.
Armed with a super-suit with the astonishing ability to shrink in scale but increase in strength, cat burglar Scott Lang must embrace his inner hero and help his mentor, Dr. Hank Pym, plan and pull off a heist that will save the world.
While there weren’t outright tests given to Thor, he wasn’t able to use Mjolnir until he had defended Asgard against evil outside forces, retrieved the apples of immortality from Storm Giants, and rescued Lady Sif from Hela . Once he had proven himself selfless and brave, Odin presented Mjolnir to Thor and held a banquet on Asgard.
Much later, Mjolnir was bequeathed to his son Thor, after he proved himself worthy through several trials.  With few exceptions, Thor has carried Mjolnir throughout his adventures. Thus, the history of Mjolnir follows that of Thor. Although Asgard was destroyed in Ragnarök , Thor and the hammer, survived. 
Some time later, a cybernetically-enhanced alien known as Beta Ray Bill arrived on Earth and proved worthy of lifting Mjolnir. Odin created a new hammer for Bill and transferred the enchantment that enabled Thor to change into mortal form to Bill's hammer. This allowed Bill to assume his pre-enhanced form but also removed the Blake persona from existence. With the aid of Nick Fury , Public Director of SHIELD , Thor adopted a new "secret identity", that of construction worker, Sigurd Jarlson. Thor did not actually become mortal in his Jarlson identity he simply dressed as a contemporary human and wore glasses. More pictures: «Thor s hammer powers dentistry».