1Cr18Mn14N双相不锈钢在腐蚀介质中的抗空蚀性能

利用磁致伸缩空蚀实验机研究了1Cr18Mn14N双相不锈钢在3%NaCl和05 mol/L HCl溶液中的空蚀行为.结果表明：在3%NaCl溶液中，低硬度的Cr18Mn14N双相不锈钢的抗空蚀性能优于高硬度的水轮机常规用材0Cr13Ni5Mo.1Cr18Mn14N双相不锈钢的空蚀破坏首先在铁素体相发生，铁素体相的失效方式为脆性失效，而奥氏体相是延性失效.奥氏体相区由滑移和孪生引起的塑性变形耗散了空泡溃灭产生的冲击能量，从而提高1Cr18Mn14N双相不锈钢的抗空蚀性能.在05 mol/L HCl溶液中，1Cr18Mn14N的抗空蚀性能不如0Cr13Ni5Mo，结果与3%NaCl溶液中的正好相反，这是由于阳极溶解和氢共同作用的结果.

CAVITATION CORROSION RESISTANCE OF 1Cr18Mn14N DUPLEX STAINLESS STEEL IN CORROSIVE MEDIA

The cavitation corrosion behavior of 1Cr18Mn14N duplex stainless steel in 3%NaCl and 0.5 mol/L HCl solutions was investigated by using a magnetostrictive-induced cavitation facility.The micrographs of damaged surfaces were observed by scanning electron microscope (SEM).The results showed that the cavitation-corrosion resistance of 1Cr18Mn14N stainless steel was higher than that of 0Cr13Ni5Mo stainless steel in 3% NaCl solution.The ferrite phase of 1Cr18Mn14N was the preferential sites for cavitation attack and its failure mode was brittle fracture,while failure on the austenite phase was a ductile failure.The excellent resistance of 1Cr18Mn14N SS to cavitation corrosion was attributed to the higher work-hardening ability of austenitic phase and consumption of impacting energy by plastic deformation involving slip and twinning.Conversely,the cavitation-corrosion resistance of 1Cr18Mn14N stainless steel was lower than that of 0Cr13Ni5Mo stainless steel in 0.5 mol/L HCl solution because the initiation and propagation of cracks for 1Cr18Mn14N stainless steel was strongly accelerated by hydrogen embrittlement and anodic dissolution.