CHARACTERIZATION OF ANISOTROPIC BEHAVIOR FOR HIGH GRADE PIPES

摘要：

　　With the developing requirement of nature gas,the property needs of steel for pipe line are higher and higher,especially in strength and toughness.It is necessary to improve the steel grade in order to ensure economic demand and safety.However,with the rise of steel grade,the differences on properties in different orientations(anisotropic behaviors)become more and more obvious after the process of hot rolling,which may affect the prediction of fracture for the pipes seriously(Thinking of isotropic mechanical properties for material in traditional predict way).In order to get the reason for anisotropic mechanics,a series of tests are carried out for high grade steel pipes,including not only mechanical properties but also microstructures.Result indicates that there are obviously anisotropic behaviors for high grade steel pipes in two orientations(rolling orientation and transverse orientation).Strength is better in T orientation because Rm is higher and Rt 0.5 rises more in T orientation,and toughness is better in L orientation because of the higher Akv and SA in L orientation under a same temperature.Banded structures are formed in T orientation,and the spatial distribution of inclusion and precipitated phases are different in T,L and S orientation.The anisotropic arrangement for the matrix in space(banded structures),which is formed after the process of hot rolling,may affect the mechanical properties in different orientation.Moreover,the elasticity modulus of particles is different from the elasticity modulus of matrix,deformation between particles and matrix may cause stress concentration,and damage forms in this place.Because of the different distribution of particles in space,the level of damage is anisotropic in different orientations,and the anisotropic mechanical properties occur finally.Therefore,the anisotropic mechanical properties are determined by the anisotropic microstructures,both the anisotropic of matrix and the anisotropic of particles are included.

关键词： anisotropic mechanical properties microstructures high grade steel pipes

作者: Yang Kun Huo Chunyong Ji Lingkang Li Yang Zhang Jiming Ma Qiurong

作者单位: Tubular Goods Research Institute of CNPC,NO.89 Jin Ye Er Lu,Xian,China,710065

会议类型: 国际会议

会议名称: Energy Materials 2014(第一届能源材料国际会议)

会议地点: 西安

会议语种:英文

页码: 759-765

在线出版日期: 2014-11-04（万方平台首次上网日期，不代表论文的发表时间）