【摘要】 本文探讨了热处理、成分、冷加工等因素对18-5型双相不锈钢应力腐蚀行为的影响.主要结果如下:经980～1050°C固溶处理后,双相不锈钢具有远比18-8型奥氏体不锈钢高得多的耐应力腐蚀性能.然而,750～900°C加热或进行冷加工变形时,由于组织结构的变化将显著降低18-5型双相不锈钢的耐应力腐蚀性能.高温加热后单相铁素体结构的出现亦会使耐应力腐蚀性能下降,因此要控制Ni_当量与Cr_当量之比值K,使K=O.42左右为宜.此外钢中第二相的存在形态对钢的应力腐蚀行为没有明显的影响.更多还原

【Abstract】 This paper was carried out to investigate the effects of composition. heat treatment, cold working etc. on stress corrosion cracking （SCC） of 18-5 type ferritic-austenitic duplex stainless steelin NaCl. MgCl₂ and high pure water by U-bend specimen testing and drop-evaporation testing. The main results obtained are as follows: （1） The 18-5 type duplex stainless steel solution-treated in the temperature range 980-1050°C has much higher resistance to SCC in chloride solution than that of 18-8 type austenitic stainless steel. The resistance to SCC. however, was rapidly reduced after heated in the temperature range 750-900°C. because of χ-phase （or σ-phase） precipitation at grain boundaries. In addition, heating in the temperature range 500-700°C for short time has less influence on resistance to SCC. （2） The formation of single phase ferrite after welding or heating at 1300°C can decrease the resistance to SCC. Therefore K value (K=Ni_eq/Cr_eq)must be controled. Suitable K value is 0.42. （3） Strain-induced martensite formed in γ-phase during cold deformation would be harmful to the resistance to SCC. （4） The morphology of second phase （γ-phase） has no influence on the resistance to SCC.更多还原