Pittsburgh cut Lockhart on Friday.
Lockhart, 23, went undrafted out of Baylor in April. He signed with the Steelers as a college free agent.
He spent two years at Texas A&M and two at Baylor, playing 28 games over four seasons. Lockhart made 54 tackles, seven sacks, a forced fumble and two pass breakups.
Last season at Baylor, Lockhart made 8.5 tackles for loss and six sacks.