Grade 904L stainless steel is a non-stabilized austenitic stainless steel with low carbon content. This high alloy stainless steel is added with copper to improve its resistance to strong reducing acids, such as sulphuric acid. The steel is also resistant to stress corrosion cracking and crevice corrosion. Grade 904L is non-magnetic, and offers excellent formability, toughness and weldability.

Grade 904L contains high amounts of expensive ingredients, such as molybdenum and nickel. Today, most of the applications that employ grade 904L are replaced by low-cost duplex stainless steel 2205.

Key Properties

The following sections describe the properties of flat rolled products in ASTM B625. The specifications may not be identical for other products such as bar, tube and pipe.

Composition

The table below provides the compositional ranges of grade 904L stainless steels:

Composition ranges of grade 904L stainless steels