Duplex stainless steels are becoming more and more frequently used in the industry. To ensure that material that is purchased is of good quality, it is necessary to have a well worked out specification to the manufacturer. The material properties of duplex stainless steels are dependent on many factors, such as the basic chemical composition, manufacturing method and heat treatment. For a consistent quality it is necessary to define measurable requirements that will ensure that the properties of the materials are fulfilled. In this paper various quality control tests for duplex stainless steel alloys are reviewed, and the applicability of these tests as well as requirements that should be met for good materials performance are discussed.

It can be concluded that there are a number of tests possible to check the quality of duplex stainless steels. Some of the tests are time consuming and does not give much more information regarding the quality of a material compared to other more easily performed tests. For new materials it is necessary to perform a wide range of tests to be able to define the range of application and suitable requirements for delivery testing. For already established materials where the properties of a good quality material is known, a more limited and less time consuming test program is preferred. Some of the more time consuming tests should therefore be amended or performed only as a prequalification test, and not as a repeated test of each new heat or order of a certain grade.

Requirements for the duplex stainless steels SAF 2304, SAF 2205 and SAF 2507 are discussed, and based on these requirements quality control programs to be used for these alloys are suggested.