纳米碳酸钙的共沉淀法合成及摩擦学性能研究

摘要

以油酸为表面活性剂,利用共沉淀合成法制备纳米碳酸钙颗粒.通过场发射扫描电镜(SEM)、X射线衍射仪(XRD)和红外光谱仪(FT-IR)对产物的形貌和结构进行表征,研究发现纳米碳酸钙颗粒呈球形,分布均匀,平均粒径约为30 nm,晶型为球霰石.将纳米碳酸钙颗粒加入到菜籽油中,考察其分散稳定性,利用四球摩擦试验机考察其摩擦学性能.结果表明:共沉淀法制备的油酸修饰纳米碳酸钙在菜籽油中具有良好的分散性,分散稳定性也有改善和提高;纳米碳酸钙具有一定的减摩和抗磨性能,这是由于摩擦磨损过程中添加剂中的Ca元素在摩擦表面形成了沉积膜,从而降低了摩擦磨损.%Calcium carbonate nanoparticles were synthesized via co-precipitation method in the presence of oleic acid.The morphologies and structure of the products were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FT-IR).Results show that spherical vaterite calcium carbonate nanoparticles with an average size of 30 nm are prepared.The dispersion stability of calcium carbonate nanoparticles in rapeseed oil was studied,and the tribological properties of the calcium carbonate nanoparticles as an additive in rapeseed oil were evaluated with a four-ball tester.The results show that these calcium carbonate nanoparticles have good dispersivity in rapeseed oil,and the dispersion stability is also improved.The calcium carbonate nanoparticles possess good performance in friction-reduction and anti-wear in rapeseed oil,because the Ca in CaCO3 nanoparticles is deposited on the worn steel surface in the process of friction,which can prevent the steel-to-steel direct contact.