Generally bearing bushes are made of

Explanation:

A bushed bearing is an improved solid bearing in which a bush of gun metal is provided.

Gun metal 

• Gunmetal, also called G Metal, variety of Bronze.
• Gunmetal is typically composed of 86% copper, 9.5% tin, 2.5% lead, and 2% zinc.
• It was used mainly for making guns and bullets. Now it is superseded by Steel.
• Gunmetal is used extensively for making heavy machinery parts as it can withstand high pressure and is corrosion resistant.