钇对EH36船板钢夹杂物特性和拉伸性能的影响

 稀土钇添加到钢中，能够有效变性夹杂物，并能引起拉伸性能的变化。为了研究钇的质量分数对夹杂物变性以及拉伸性能的影响，以EH36船板钢为研究对象，采用扫描电子显微镜、能谱等分析手段，对原始钢以及加入不同量稀土的试样进行夹杂物以及拉伸性能的测试分析。结果表明，稀土元素钇能有效变性夹杂物，将长条状的硫化锰夹杂物或者复合的硫化锰夹杂物变性为以Y Al O为核心的、外圈为稀土氧硫化物的球状夹杂物。对其力学性能检测发现，随着稀土加入量的提高，其抗拉强度和屈服强度显著提高，其中钇质量分数为0.055%的试样具有较好的夹杂物变性形貌和较好的抗拉强度和屈服强度。

Effect of Y on inclusions characteristics and tensile #br# properties in EH36 shipbuilding steel

 Adding rare earth Y into steel can modify inclusions effectively in steel，bringing the changes of tensile properties. In order to study the effect of different content of Y on inclusions modification and tensile properties in steel，EH36 shipbuilding steel was chosen to analyze the inclusions in origin steel and in test steel with different Y addition using scanning electron microscope (SEM) and energy dispersive spectroscope (EDS). Tensile properties were also explored and tested. The results showed that rare earth Y could modify effectively the inclusions. The origin strip of MnS inclusions or the composite manganese sulfide inclusions could be modified into the spherical inclusions which the core was Y Al O and the outer ring was rare earth oxysulfide. For mechanical properties，the results showed that the tensile strength and yield strength of shipbuilding steel were improved significantly with the Y addition increasing. The sample with the Y addition of 0.055% had the best morphology of inclusions modification and better tensile strength and yield strength.