论文标题
脂肪酸在铁面上的吸附特性，$σ$ 3（111）晶粒边界
Adsorption property of fatty acid on iron surface with $Σ$3(111) grain boundary
论文作者
论文摘要
降低钢表面边界摩擦系数是提高机器（例如汽车发动机）效率的关键技术之一。已经表明，使用烃润滑剂分子在滑动测试中纳米结构钢表面上的边界摩擦小于正常钢表面的摩擦。纳米结构和正常表面之间的主要区别在于晶界和其他表面缺陷的密度。表面缺陷可以吸引润滑分子并增强金属表面上的润滑膜形成。这可能是诱导纳米荷表面摩擦降低的机制之一。在这项工作中，使用第一原理计算，已经研究了润滑剂分子（脂肪酸）在缺陷的铁表面上的可吸附性。将具有对称倾斜σ3（111）的Fe（110）表面的可吸附性与干净的Fe（110）表面进行了比较。结果，我们发现该分子被吸附在接近晶界的位点（平均为0.77 eV），而不是在没有晶界的Fe表面上。
Reducing the coefficient of boundary friction on steel surfaces is one of key technologies to improve the efficiency of machines such as automotive engines. It has been shown that the boundary friction on nanostructured steel surfaces in the sliding test using hydrocarbon lubricant molecules is smaller than the friction of normal steel surfaces. The main difference between the nanostructured and a normal surfaces is the density of grain boundaries and other surface defects. The surface defect can attract lubricant molecules and enhance lubricating film formation on metal surfaces. This can be one of the mechanisms that induce the friction reduction on the nanosructured steel surface. In this work, using first principles calculations, the adsorbability of a lubricant molecule, a fatty acid, on a defected iron surfaces has been studied. Adsorbability of the Fe(110) surface with symmetrical tilt Σ3(111) grain boundary was compared to that of the clean Fe(110) surface. As a result, we found that the molecule is adsorbed on sites close to the grain boundary more strongly (0.77 eV in average) than on the Fe surface without grain boundary.
