At present, the traditional cutting fluids usually containing the chemical toxicity or physical irritating ability will cause illness or injury in workers. Therefore, research on eco-friendly cutting fluids has become a mainstream trend in the development of metalworking process with a type of coolant and lubricant. In this present work, three types of eco-friendly cutting fluids including distill water, castor oil, linear alkyl benzene sulphonic acid (LAS-Na) and nanographite by different proportion under ultrasonic vibration were prepared. Then they were assessed by the comparisons of cutting forces in broaching under the condition of micro-atomization spraying. After that, the optimum ratio of each type of cutting fluid was gained based on the reductions of broaching forces. Physical stability, droplets distribution and wettability of those optimal type of eco-friendly cutting fluid were measured. On the basis of characteristics, the metal-cutting principle with those experimental types of cutting fluids was discussed. Results shows that the surfactant of LAS-Na could effectively prevent the coalescence of oil droplets and decrease the average diameter of droplets so that enhanced wettability, but the nanographite was strongly influenced by the cleaning effect of LAS-Na. Moreover, reduction in broaching force was caused by the mechanism of the best adsorption and the best permeability with the effect of the surfactant of LAS-Na.

目前，传统的切削液通常含有化学毒性或物理刺激性，会导致工人生病或受伤。因此，研究环保型切削液已成为一种冷却剂和润滑剂金属加工工艺发展的主流趋势。在目前的工作中，通过超声振动制备了不同比例的蒸馏水、蓖麻油、直链烷基苯磺酸（LAS-Na）和纳米石墨三种环保型切削液。然后通过微雾化喷涂条件下拉削切削力的比较对它们进行了评估。之后，根据拉削力的降低，得出每种切削液的最佳配比。物理稳定性，测量了这些最佳类型的环保切削液的液滴分布和润湿性。根据特点，讨论了这些实验型切削液的金属切削原理。结果表明，LAS-Na表面活性剂能有效阻止油滴聚结，降低油滴平均直径，从而增强润湿性，但LAS-Na的清洗效果对纳米石墨的影响较大。此外，拉削力的降低是由LAS-Na表面活性剂作用下吸附最佳、渗透性最佳的机理引起的。结果表明，LAS-Na表面活性剂能有效阻止油滴聚结，降低油滴平均直径，从而增强润湿性，但LAS-Na的清洗效果对纳米石墨的影响较大。此外，拉削力的降低是由LAS-Na表面活性剂作用下吸附最佳、渗透性最佳的机理引起的。结果表明，LAS-Na表面活性剂能有效阻止油滴聚结，降低油滴平均直径，从而增强润湿性，但LAS-Na的清洗效果对纳米石墨的影响较大。此外，拉削力的降低是由LAS-Na表面活性剂作用下吸附最佳、渗透性最佳的机理引起的。