ISO 17781:2017规定了在固溶退火条件下提供的铁素体/奥氏体（双相）不锈钢部件和在焊态条件下提供的制造焊缝中，与相关性能相关的微观结构表征的质量控制试验方法和试验条件。 ISO 17781:2017补充了有关破坏性试验方法的相关产品和制造标准，包括试样取样、试验条件和试验验收标准，以显示双相不锈钢中没有有害的金属间相和沉淀物。 此外，本文件规定了测试实验室的测试和测试结果文件。 注1:本文件基于双相不锈钢在海上石油和天然气行业应用的经验，包括上部结构和海底碳氢化合物服务、海水服务以及结构使用。 注2:在采用阴极保护的海底应用中，奥氏体间距与双相不锈钢对氢致应力开裂（HISC）的敏感性有关。这不属于本文件的范围。参考DNV/GL RP- F112[4]。

ISO 17781:2017 specifies quality control testing methods and test conditions for the characterization of microstructure in relation to relevant properties in ferritic/austenitic (duplex) stainless steel components supplied in the solution annealed condition and fabrication welds in the as welded condition. ISO 17781:2017 supplements the relevant product and fabrication standards with respect to destructive testing methods including sampling of test specimens, test conditions and test acceptance criteria to show freedom from deleterious intermetallic phases and precipitates in duplex stainless steels. In addition, this document specifies the documentation of testing and test results by the testing laboratory. NOTE 1 This document is based upon experience with duplex stainless steels in offshore oil and gas industry applications including topside and subsea hydrocarbon service, sea water service, as well as structural use. NOTE 2 The austenite spacing is relevant to the susceptibility of duplex stainless steels to hydrogen-induced stress cracking (HISC) in subsea applications where cathodic protection is applied. This falls outside the scope of this document. Reference is made to DNV/GL RP-F112[4].