Thyssenkrupp's mining business, which competes with Metso Outotec, Sandvik and Atlas Copco, is expected to fetch a "low triple-digit million euro" sum.
IGO, which completed a $1.4 billion deal to buy a stake in Tianqi Lithium's Australian assets last month, has been looking to focus on its nickel and lithium ventures.
Negotiations over the past two months between the company and its powerful workers' union over a new labor contract have been conducted in utmost secrecy.