Micromachining process with ductile tooling

提出的研究是关于开发一种新的自动化制造工艺，旨在取代大规模生产注塑模具制造过程中繁琐的手工抛光操作。注塑模具是昂贵的设备件，需要以合理的价格生产，任何一种聚合物零件都包含在各种各样的消费产品中，如汽车、电脑、手机、电动工具、玩具等。注射模具的主腔是用强大的数控铣床用一块工具钢材料雕刻出来的，然后是二次手工加工，以获得所需的表面光洁度。高达30%的模具生产成本与后二次精加工有关，因为这些操作大多涉及手工。在提出的研究中，我们的目的是设计一个基于EDµM电火花加工和UAµM超声磨料加工原理的自动化制造工艺。在EDµM中，工具和待抛光工件之间产生放电。每次放电都攻击表面，使少量材料蒸发。对于UA μ M，超声波激活工具产生强大而小的位移，以推动工件表面的磨料颗粒，从而去除或置换少量材料。这种方法的新颖之处在于在同一数控机床内结合两种工艺的优点的可能性。这种特性是通过开发一种延展性、导电性和耐磨的聚合物工具而实现的，这种工具一旦被压缩成型，就可以作为一种工具，在最硬的金属中执行任何一种材料去除技术。整个过程是环保的，因为它是在空气中或与研磨颗粒（如沙子）进行的，并且不会产生有毒的副产品。模具制造业在加拿大有30至40亿美元的业务，由于工资较低，来自新兴国家的竞争很激烈。因此，建议的研究努力将回馈给我们的模具制造业的全球竞争优势。

The proposed research is about the development of a novel automated manufacturing process designed to replace tedious hand-polishing operations involved in the fabrication procedures of mass production injection molds. Injection molds are expensive pieces of equipment required to produce at reasonable price, any kind of polymer parts contained in a large variety of consumer products such as cars, computers, cell phones, electric tools, toys and others. The main cavity of an injection mold is carved out of a block of tool steel material with a powerful CNC milling machine, followed by secondary manual processes to obtain the desired surface finish. Up to 30% of the mold production cost is related to the latter secondary finishing processes because most of these operations involve handwork. In the proposed research our intention is to design a automated manufacturing process, based on the EDµM electric discharge µmachining and UAµM ultrasonic abrasive µmachining principles. In EDµM, electric discharges are produced between a tool and the workpiece to be polished. Each discharge attacks the surface peeks and vaporise tiny amount of the material. For UAµM, an ultrasonic activated tool generates powerful yet small displacement to propel abrasive particles over the surface of the workpiece which removes or displaces tiny amount of material. The novelty of this approach resides in the possibility to combine the advantages of both processes within the same numerically controlled machine tool. Such characteristic is made possible by the development of a ductile, electrically conductive and wear resistant polymer tool which, once compression molded can be used as a tool to perform either material removal techniques in the hardest metals. The entire process is environmentally friendly since it is conducted in air or with abrasive particles (like sand) and does not generate toxic by-products. Mold manufacturing represents a 3 to 4 billion dollars business in Canada, and competition from emerging countries is fierce because of lower wages. Thus, the proposed research endeavours giving back a worldwide competitive edge to our mold manufacturing industry.