Eradicating hydrofluoric acid from metal etching

在过去的50年里，制造商准备金属高价值零件表面的方法几乎没有改变，依赖于在大量腐蚀性和通常是有毒的酸中进行基于浴液的化学蚀刻，然后对大型缺陷进行人工目视检查。这造成了难以处理的大量浪费，同时对成品零件应用了过于慷慨的安全系数，因为目前并不是所有现有的缺陷都可以在生产线过程中识别和量化。这首先是在产生大量废物方面效率低下，尽管有可能使环境和使用者暴露在腐蚀性和有毒化学品中。其次，效率低下的原因是部件寿命显著缩短，加载条件比可能的情况更轻，这增加了维护干预。我们将创建一套新的工艺，通过使用少量非危险化学品(电解液)应用定向带电流体喷射来蚀刻相同的材料。这些电解液将被再循环，并将创建一个自动健康监测系统，以确保在零件表面保持适当的刻蚀响应，并确保资源效率。废电解液将被过滤，含有金属的碎片将返回制造供应链，大大减少化学品的数量，并确保所应用的化学品对环境和最终用户构成的风险大大降低。我们将在蚀刻过程中和之后观察生成的表面，通过量化表面的各个方面，我们将获得对材料和先前制造工艺的成功的有价值的见解。我们将获得的信息与材料的排列(微结构)和表面缺陷的存在有关。这两者都会影响最终零件的质量，目前，具有大缺陷或不适当微结构的零件经常被报废，通常是在昂贵的制造工艺之后。我们将创建决策系统，与我们的合作伙伴一起使用自动化方法，使用可应用于工厂的快速技术来识别和量化零件表面的微观结构、缺陷大小及其出现情况。从这些特征来看，机器主导的决策将驱动加工策略。从这一步提取的信息将被反馈到电化学喷射系统，以实现有针对性的返工。在这里，表面缺陷可以通过选择性电化学蚀刻来消除，方法是将给定零件上的缺陷位置和大小提供给新的蚀刻系统。这将使用配备自动蚀刻的机器人来执行，并将利用电化学喷射技术的能力来执行不同模式的材料去除和创造不同的表面响应。通过在单个制造步骤中识别、量化和消除零件中的缺陷，预计该系统将能够在相对较低的成本点和制造商要求的时间尺度上显著降低高价值零件的废品率。此外，还将提取与缺陷和微结构有关的信息，并向制造商和操作员提供信息，通过允许部件特定的寿命和加载条件来优化效率。因此，这个项目以可持续发展为目标，同时为高价值制造商提供改变游戏规则的技术。

The ways in which manufacturers prepare the surfaces of metal high-value parts has changed little over the last 50 years, reliant on bath-based chemical etching in large volumes of corrosive and often toxic acids, followed by manual visual inspection for large defects. This creates large amounts of waste that is difficult to handle, while overly generous safety factors are applied to finished parts as currently not all present defects can be identified and quantified in production line processes. This represents inefficiency firstly in the generation of large volumes of waste, notwithstanding the potential for environmental and user exposure to corrosive and toxic chemicals. Secondly, inefficiency arises from the part lifetimes being significantly shorter and loading conditions lighter than possible, which increases the maintenance intervention.We will create a new set of processes that can etch the same materials by applying targeted electrically charged fluid jets using small volumes of non-hazardous chemicals (electrolytes). These electrolytes will be recirculated and an automatic health monitoring system will be created to ensure appropriate etching response is maintained at the part surface, and ensure resource efficiency. Waste electrolyte will be filtered and metal-containing debris will be returned to the manufacturing supply chain, significantly reducing the volumes of chemicals, and ensuring that the chemicals applied present much reduced risk to the environment and the end user. We will observe generated surfaces during and following etching, and by quantifying aspects of the surface, we will gain a valuable insight into the material and the success of the preceding manufacturing process. The information we will acquire relates to the arrangement of the material (the microstructure) and the presence of surface defects. Both of these can affect the quality of the final part and currently, parts with large defects or inappropriate microstructures are often scrapped, often after expensive manufacturing processes. We will create decision-making systems, using automation approaches with our partners to identify and quantify microstructures, and defect sizes and their occurrence over the part surface using fast techniques that can be applied in the factory. From these characteristics, machine led decision making will drive the processing strategy. Information extracted from this step will be fed back to the electrochemical jet system to enable targeted reworking. Here, surface defects can be removed by selective electrochemical etching, by supplying defect locations and sizes on a given part back to the new etching system. This will be performed using an automated etching equipped robot and will exploit the electrochemical jet technique's capability to perform different modes of material removal and create different surface responses. By identifying, quantifying and removing defects within parts in one single manufacturing step, it is expected that the system will be capable of significantly reducing scrappage rates of high-value parts at a relatively low cost point and on timescales demanded by manufacturers. Furthermore, information pertaining to defects and microstructures will be extracted and provide information to both the manufacturer and the operator, optimising efficiency by allowing part-specific lifetimes and loading conditions. Hence this project with deliver against a sustainability objective while providing a game changing technology for high value manufacturers.