Kobe Steel Ltd. said Monday it has begun mass production at its aluminum forging plant in Jiangsu Province, China, after completing an expansion to double output capacity and add melting and casting processes.

Kobe Steel said the ¥4.5 billion expansion, initiated in December 2011, was driven by growing demand for aluminum automotive suspensions driven by China’s growing automobile industry and a trend toward lighter vehicles.

The plant is run by Kobe Steel subsidiary Kobe Aluminum Automotive Products (China) Co., a joint venture with Mitsui & Co. and Toyota Tsusho Corp.