West Midlands Fire Service sent six crews to tackle the blaze on Spring Road Industrial Estate, just off Lanesfield Drive, Wolverhampton.
Residents in the surrounding area were warned to keep doors and windows closed as a precaution.
Images taken from the scene show a large heap of scrap metal completely blackened by the fire as authorities estimate around 100 tonnes were destroyed.
The fire service believe the fire started ‘accidentally’ as crews remain on scene ensuring hotspots can be reached and dealt with.
A spokesperson for West Midlands Fire Service said: “We were alerted shortly before midnight on Friday (5 Dec) to a fire involving a large quantity of scrap metal at an industrial site off Lanesfield Drive, Lanesfield, Wolverhampton.
“As of 11am on Saturday, six fire engines crewed by around 30 firefighters remained at the scene. They are expected to be there throughout the day. The fire involves an estimated 100 tonnes of scrap metal in an open yard and is believed, at this stage, to have started accidentally.
“People who live or work nearby and can see or smell smoke are advised to keep their doors and windows closed as a precaution. We would also ask people to avoid the area while our work continues and smoke remains in the area – including on a nearby canal towpath.
“Progress is being made, although it is slow because of the amount of material involved and the need to move it safely.
“Water to fight the fire is being taken from a nearby canal. On-site staff have been working with our crews and using diggers to pull apart and move scrap so that deep-seated hot spots can be reached and extinguished.
“We have been working closely with a range of partners, including the Environment Agency, Severn Trent, the City of Wolverhampton Council, Cadent Gas, National Grid, the Canal and River Trust. Others including Network Rail, West Midlands Police and the ambulance service have also been informed.”