双相不锈钢含有铁素体+奥氏体两相组织，具有良好的机械和腐蚀性能，尤其以出色的抗应力腐蚀开裂性能而著称。但双相不锈钢在特定的环境和拉应力共同作用下，会出现应力腐蚀开裂现象，由于应力腐蚀开裂通常难以被发现，从而导致灾难性的事故。在此基础上，从材质的成分和金相组织，温度、pH、氯离子和氧气浓度等工况环境，冷变形和残余应力等方面总结了影响双相不锈钢应力腐蚀开裂的因素。结合双相不锈钢的使用环境和应力特点，阐述了双相不锈钢的应力腐蚀开裂机理，包括电化学阳极溶解理论、氢脆机制、膜破裂理论、化学脆化一机械破裂两阶段理论、应力吸附破裂理论。依据应力腐蚀开裂机理，结合影响因素，通过合理添加合金元素开发出新的双相不锈钢、双相不锈钢等离子碳氮共渗或表面涂层、热处理工艺等方法，有效地降低双相不锈钢应力腐蚀开裂的敏感性。最后，从双相不锈钢应力腐蚀开裂机理和防护技术两方面展望了双相不锈钢应力腐蚀开裂未来的研究方向，从本质上减少应力腐蚀开裂事故的发生，保障生产的“安稳长满优”。

Duplex stainless steel contains ferrite + austenite two-phase structure, has good mechanical and corrosion properties, especially for its excellent stress corrosion cracking resistance. However, stress corrosion cracking (SCC) also occurs in duplex stainless steel under the combined action of specific environment and tensile stress. Because SCC is usually not found, it leads to catastrophic accidents. On this basis, from the material composition and microstructure; Temperature, pH, chloride ion and oxygen concentration, etc; The factors influencing the stress corrosion cracking of duplex stainless steel were summarized from the aspects of cold deformation and residual stress. Combined with the service environment and stress characteristics of duplex stainless steel, the stress corrosion cracking mechanism of duplex stainless steel was expounded, including electrochemical anodic dissolution theory, hydrogen embrittlement mechanism, membrane cracking theory, chemical embrittlement mechanical cracking two-stage theory, stress adsorption cracking theory. According to the stress corrosion mechanism，and taking the influencing factors into consideration，stress corrosion cracking sensitivity of the duplex stainless steel can be effectively reduce by reasonable addition of alloying elements to develop new duplex stainless steel，plasma carbonitriding or surface coating，heat treatment，modification treatment of duplex stainless steel．Finally, the future research direction of stress corrosion cracking of duplex stainless steel is prospected from two aspects of stress corrosion cracking mechanism and protection technology, so as to reduce the occurrence of stress corrosion cracking accidents in essence and ensure the "safe, stable and excellent" production.