摘要
用X射线衍射仪和透射电镜对1Cr18Ni9Ti不锈钢高能喷丸处理试样表面形成的纳米晶组织进行了表征。用阳极动电位极化曲线测定和点蚀试验研究了喷丸表面纳米化对1Cr18Ni9Ti不锈钢耐蚀性的影响,并借助扫描电镜对点蚀试样表面形貌进行了表征。结果表明,喷丸导致试样表面层形成平均尺寸约18 nm的纳米晶组织,即实现了表面纳米化,并产生了体积分数约15%的形变诱发α马氏体。随距喷丸表面深度增大晶粒尺寸逐渐增大,α马氏体的体积分数逐渐减小。喷丸表面纳米化可以明显改善1Cr18Ni9Ti不锈钢样品在3.5%NaCl溶液中的动电位极化特性。与原始粗晶试样相比,喷丸表面纳米化试样更容易形成稳定的腐蚀钝化膜,其抗氯离子腐蚀性能显著提高。
Nanocrystalline microstructure in the surface layer of 1Cr18Ni9Ti stainless steel induced by high-energy shot peening is characterized by means of X-ray diffractometry and transmission electron microscopy. The effects of surface nanocrys tallization induced by shot peening on polarization behavior and corrosion resistance of the steel are also investigated by polarization curves and pit corrosion tests. And the surface morphologies of the corrosion samples have been characterized by scanning electron microscopy. The results show that shot peening can cause the surface nanocrystallization, that is, the nanocrystalline microstructure with average grain size of-18 nm forms in the surface layer of the sample, and furthermore, induce α-martensite of about 15% in volume fraction. With increasing the depth from the shot-peened surface, the grain size increases, but the volume fraction of ct martensite decreases. The surface nanocrystallization can improve the potentiodynamic polarization behavior of 1Cr18Ni9Ti stainless steel in 3.5% NaCl solution. Comparing to as-received coarse crystalline counterpart, the passive film on the surface of shot-peened sample is easier to form and more stable. Shot peening-induced surface nanocrystallization can markedly enhanced the corrosion resistance of 1Cr18Ni9Ti stainless steel in the chlorion-contained solution.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2005年第9期51-54,共4页
Journal of Mechanical Engineering
关键词
1Crl18Ni9Ti不锈钢
表面纳米化
喷丸
耐蚀性
1Cr18Ni9Ti stainless steel Surface nanocrystallization Shot peening Corrosion resistance
作者简介
王天生，男，1963年出生，教授。主要研究方向为材料微观结构表征及金属材料强韧化，获国家及省部级科技进步奖5项，发表论文50余篇。E-mail：tswhang@ysu．edu．cn
