Dubai International Capital, an arm of the Dubai Holding company, announced on Sunday that it had "concluded the acquisition contract" for Britain's Doncasters Group, in a deal that has been estimated at $1.27 billion.
Doncasters in turn controls the US company Ross Catherall whose plant in Georgia supplies parts for army tanks and helicopters.
Samir al-Ansari, the executive president of Dubai International Capital, said the "takeover of Doncasters Group gives it the opportunity to move forward with its strategy of equipping itself with a diversified investment portfolio ... in the world".
George Bush, the US president, said on April 29 that he had endorsed the deal after the Committee on Foreign Investments in the United States gave it the green light.
The deal has echoes of the transaction involving Dubai-owned DP World, which had won the rights to operate six US ports through its takeover of British shipping company P&O.
But DP World relinquished its rights in March due to an outcry in the US Congress over the security implications of a state-owned Arab company gaining control of US port operations.