Armor Plates for US Army Vehicles Never Passed Required Test

The US Army’s Joint Light Tactical Vehicle is the second-generation successor to the iconic Humvee, used by the American military and about a dozen other nations since the last Iraq war to protect troops from bullets, mines and improvised explosive devices.

But for about two years, employees at Evraz North America Inc., a Russian-owned steel plant operator in the US, falsified quality control test results on some armored plating for the vehicle’s manufacturer, according to an internal report seen by Bloomberg News and senior officials at the company, who asked not to be identified because the information isn’t public.

The incidents ...