拉拔模具工作表面微纳仿生织构软涂层构建及协同润滑机理研究

The sliding friction when wire produced plastic deformation caused the severe wear of conical die. In the tribology design, the wear of material is closely related to the lubrication of work surface, our team found that developed conical die with hydrodynamic lubrication and self-lubricating properties has become the key to increase the wear resistance of it. Research shows that the prepared micro-nano bionic texture combined with self-lubricating soft coating on the friction surface is an effective way to solve the problem. Therefore, our team intends to study the bionic tribology, solid lubrication technology and other basic theory. Our team applies the magnetron sputtering technique, femtosecond and picosecond laser processing technology and vacuum hot pressing sintering method combined with theoretical analysis, numerical simulation, experimental validation. The research includes are as follows: 1. system research on tribology design of micro-nano bionic texture on conical die working surface; 2. detailed study of preparation key technology of soft coating on the working surface and forming mechanism of self-lubricating film; 3. exploration of collaborative lubricating effect and wear resistance mechanism caused by hydrodynamic lubrication based on micro-nano bionic texture and self-lubricating produced by soft coating. Our team will produce conical die with the micro-nano bionic texture and soft coating on working surface, and the micro-nano bionic texture form hydrodynamic lubrication in the friction process, and the soft coating will drag and cover a self-lubricating film on worn surface. The two methods play a synergistic effect for friction reduction and wear resistance. The technology will enhance the service life of the conical die and the surface quality of wire rod. Related research will be applied to other friction parts.

线材塑性变形中的滑动摩擦导致拉拔模具磨损严重。在摩擦学设计中，材料的磨损与工作表面的润滑密切相关，课题组发现研制具备流体动压润滑及自润滑特性的模具成为提高耐磨性的关键。研究表明：摩擦表面微纳仿生织构结合自润滑软涂层是解决问题的有效途径。因此，课题组拟在仿生摩擦学、固体润滑技术等基础理论指导下，采用磁控溅射技术、飞秒皮秒激光加工技术及真空热压烧结等方法结合理论分析、数值仿真、实验验证进行如下工作：1.系统研究拉拔模具工作表面微纳仿生织构的摩擦学设计；2.详细研究模具工作表面软涂层制备关键技术及自润滑成膜机理；3.探索工作表面微纳仿生织构流体动压润滑及软涂层自润滑协同润滑效应及减摩抗磨机理。拟得到微纳仿生织构软涂层拉拔模具工作表面，微纳仿生织构在滑动摩擦过程中形成流体动压润滑，软涂层在摩擦表面形成自润滑膜，起到协同减摩抗磨作用，提高模具使用寿命和线材表面质量，并推广应用于其他摩擦构件。

线材塑性变形中的滑动摩擦导致拉拔模具磨损严重。在摩擦学设计中，材料的磨损与工作表面的润滑密切相关，课题组发现研制具备流体动压润滑及自润滑特性的模具成为提高耐磨性的关键。研究表明：摩擦表面微纳仿生织构结合自润滑软涂层是解决问题的有效途径。因此，课题组在仿生摩擦学、固体润滑技术等基础理论指导下，采用磁控溅射技术、飞秒皮秒激光加工技术及真空热压烧结等方法结合理论分析、数值仿真、实验验证进行如下工作：1.系统研究了拉拔模具工作表面微纳仿生织构的摩擦学设计，澄清了异形微纳仿生织构单向收敛动压减摩抗磨机理、建立了多种尺度单向收敛异形仿生织构应用于拉拔模具，分析了拉模工面仿生织构参数化设计及可靠性应用之间的本构关系，突破了原拉模工面摩擦系数大、磨损严重的使用局限，改善了重载工况下摩擦表面磨损剧烈的科学难题，满足了拉模设计需求，实现了多种不同工况下单向收敛微纳织构工作表面拉模的可靠应用。2.详细研究了模具工作表面软涂层制备关键技术及自润滑成膜机理，设计了适用于复杂工况下的拉模工面磁控溅射表面涂层技术，澄清了基体、涂层之间的结合力、表面涂层自润滑机理及制备技术，形成了高结合强度和低摩擦系数工作表面，克服了近壁面重载高温导致的表面磨损严重问题，提高了模具使用寿命，解决了恶劣条件下大载荷高频幅磨损失效的问题。3.探索了工作表面微纳仿生织构流体动压润滑及软涂层自润滑协同润滑效应及减摩抗磨机理，提出了微纳仿生织构及自润滑软涂层协同润滑减摩抗磨的思路，强化了拉模表面抗疲劳性和耐磨性，解决了拉模长期使用中疲劳磨损和微动磨损导致的失效问题，提高了长期使役寿命。通过以上研究，得到了微纳仿生织构软涂层拉拔模具工作表面，微纳仿生织构在滑动摩擦过程中形成流体动压润滑，软涂层在摩擦表面形成自润滑膜，起到了协同减摩抗磨作用，提高了可模具使用寿命和线材表面质量，并成功推广应用于制动盘、刀具、盾构机刀具、抛丸机叶片等摩擦构件。