DMTD在Ti-DLC自配副摩擦界面的吸附及摩擦学行为的研究

采用非平衡磁控溅射技术制备了Ti掺杂的类金刚石(Ti-DLC)薄膜,用X射线衍射仪(XRD)和扫描电子显微镜(SEM)分别对薄膜结构和断面致密度进行了分析.用球盘式往复摩擦试验机考察了薄膜与以聚a-烯烃(PAO)为基础油,2,5-二巯基-1,3,4-噻二唑(DMTD)衍生物作为添加剂复合后的摩擦学性能,同时采用X射线光电子能谱(XPS)对摩擦后的磨痕进行元素分析,并进行动力学计算.结果表明:添加剂分子DMTD分子以巯基S作为吸附点吸附在摩擦界面,扩散是吸附的控制因素,吸附过程跟表面的覆盖度无关,符合Langmuir吸附模型.最后讨论了液体添加剂分子在DLC表面的吸附过程和气体分子吸附过程不同的可能原因.

基于铣削力模型的NOMEX蜂窝固持工艺优化

为了解决蜂窝芯高速铣削加工过程中出现的固持可靠性差以及加工精度与效率低的问题,需要准确建立铣削参数与固持工艺参数之间的关系模型.提出了一种基于磁场和摩擦吸附原理的蜂窝芯固持方法,克服了传统双面胶带固持方法带来的种种弊端.利用有限元模拟试验建立了加工误差、铣削力、固持工艺参数之间的关系模型,并对固持工艺参数进行优化分析.针对薄厚度蜂窝的加工实验结果表明,应用该模型对固持参数进行优化,可减少70%的铁粉填充量,有效地提高了固持率,同时保证了±0.1 mm级的加工精度.

纸基蜂窝零件夹持方法研究

为了解决当前纸基蜂窝零件高速铣削加工夹持方法的可靠性和稳定性较差以及加工精度低的缺点,提出一种基于磁场和摩擦吸附原理的夹持方法.该方法利用灌入蜂窝芯中铁粉的自重以及外加磁场对铁粉的吸引力,在铁粉与蜂窝侧壁之间以及蜂窝芯与夹具平台之间产生可以控制的摩擦力,利用摩擦力的作用达到在高速加工过程中对纸基蜂窝芯零件的夹持.通过实验证明,该方法简单易行,适合于大批量生产.

纸基蜂窝芯零件高速铣削固持系统设计

为了提高纸基蜂窝芯零件高速铣削时的加工精度,降低加工成本,提出了两种基于磁场和摩擦吸附固持原理固持平台的设计方案,即采用电磁装置激发磁场和采用永磁材料激发磁场,并进行了加工制造。通过理论分析和计算确定了在给定铣削力的条件下,可靠固持蜂窝芯材料所必需的磁感应强度。利用有限元软件分析了磁极高度、厚度以及磁极间距等结构参数对磁感应强度的影响。利用制造的两套固持平台进行了铣削试验,得到了满意的固持效果。

纸基蜂窝零件数控加工装夹系统中填料方法的研究

提出一种基于摩擦吸附原理的装夹定位方法。介绍了装夹定位方法以及填料装置设计、填料高度控制等内容。以某型号飞机方向舵蜂窝零件为例 ,研究了安全填料高度的计算方法。实践表明 ,采用该装夹定位方法 ,可以有效地提高蜂窝零件的加工精度和加工效率。

Competitive Adsorption of Anticorrosion and Antiwear Additives

Simulated adsorptive experiments using the axletree and lubricating oil containing anticorrosion additive were conducted,and the UV absorbance of the lubricating oil before and after the adsorptive experiments was measured.Through the UV spectral measurements the difference in UV absorbance of the lubricating oil before and after the adsorptive experiments was identified,the adsorbed quantity of anticorrosion additive in the interfacial film between lubricating oil and bearing was calculated using the Lambert-Bell principle to verify the adsorption of corrosion inhibitor on the surface of friction pairs.Adsorption experiments on lubricating oil containing both antiwear and anticorrosion additives were carried out and the UV absorbance of lubricating oil samples before and after the experiments was measured to determine the difference in the UV absorbance among lubricating oil samples with the same mass fraction of anticorrosion additive and different mass fractions of antiwear additive.By measuring the ultraviolet spectral absorbance of lubricating oil samples and calculating the adsorbed quantity of anticorrosion additive in the interfacial film it was possible to determine the influence of antiwear additive on the quantity of adsorbed anticorrosion additive on the surface of friction pairs and verify the competitive adsorption relationship between the antiwear additive and the anticorrosion additive.