新型低碳贝氏体钢的力学与腐蚀疲劳性能

Mechanical and corrosion fatigue properties of a new low carbon bainitic steel

为研究低碳贝氏体钢在热处理后的力学、腐蚀疲劳性能,采用扫描电子显微镜、透射电镜、X射线衍射分析研究了一种新型贝氏体钢力学性能,并在自来水和盐水腐蚀介质中研究了其腐蚀疲劳性能.结果表明:与轧材比较,A、B、C钢轧材经正火回火热处理后,表现出更优异的综合力学性能和抗腐蚀疲劳性能;而含Si高的A钢具有更优异的韧塑性及抗腐蚀疲劳性能.含Si的贝氏体钢中的贝氏体铁素体(BF)板条间残余奥氏体(Ar)膜对氢致裂纹的扩展速率有突出的抑制作用.

The mechanical properties and corrosion fatigue properties of low carbon bainite steel after heat treatment under water and salt water conditions were investigated by scanning electron microscopy（SEM）,transmission electron microscope（TEM） and X-ray diffractometer（XRD）.The results indicated that,compared with as-rolled specimens,A,B,C steel after heat treatment showed more excellent toughness and ductility mechanical properties.Additionally,specimen of A with more silicon content showed superior mechanical properties and corrosion fatigue performance which was attributed to more retained austenite（Ar） between bainite ferrites（BF） reducing the propagation rate of Hydrogen induced crack.