Vol. 21
July Issue
Year 2020


in Vol. 21 - July Issue - Year 2020
Surface Enhancement: Opportunities in the New Normal

Dr. Wong Chow Cher from Advanced Remanufacturing and Technology Centre (ARTC), Singapore

Digital Shot Peening platform, developed in collaboration with a Singapore company, Abrasive Engineering

Abrasive flow machining, one of the techniques to polish complex internal channels of AM components. Simulation capabilities are also being developed.

We had an opportunity to talk to Dr. Wong Chow Cher from Advanced Remanufacturing and Technology Centre (ARTC), Singapore. Built upon a public-private partnership model, ARTC has a membership consortium with over 80 members, ranging from global multinational corporations (MNCs) to local small and medium enterprises (SMEs). ARTC focuses on advanced manufacturing and remanufacturing and serves to accelerate the transfer of innovation from applied research to industrial applications. Dr. Wong is the Technical Director who oversees two out of six technology groups in ARTC – Data-driven Surface Enhancement and Intelligent Product Verification. In addition, Dr. Wong is also the Coordinating Director of Business Development and Industrial Additive Manufacturing Facility. The conversation centered around ARTC technology roadmap related to surface enhancement and how that is being reshaped by COVID-19.

(?) MFN: Dr. Wong, thank you for taking the time to do this with us. I can’t help but notice that the ARTC consortium has a stellar lineup of industry partners that include Rolls-Royce, IHI, DMG Mori and ABB, just to name a few. I would imagine though, that the problem statements must be diverse – how do you satisfy these diverse needs?

(!) C. C.: Thank you, it’s my pleasure. You will be surprised to find that there is quite a fair bit of common ground among companies in different industrial sectors. Many of these companies share interests in ‘horizontal’ technologies such as additive manufacturing, robotics, inspection technology and digitalization. For sure, surface enhancement is more targeted at sectors such as aerospace and transport, but they are increasingly intertwined with these horizontal technologies.

(?) MFN: Does that have something to do with the name of your department… "Data-driven Surface Enhancement". Can you please elaborate a little on that?

(!) C. C.: Indeed. Today, many surface enhancement processes are based on know-how, best practice, and experience of technicians. The challenge is that these are often difficult to capture and transfer to other people, especially younger people. With lower number of youngsters joining the workforce in this field, replacing these talents is increasingly difficult. Therefore, we believe that it is critical that surface enhancement processes are informed and driven by data, not fully substituting for human knowledge, but allowing this to be a reasonably powerful sidekick.

(?) MFN: Right. I’ll now move on and ask about what your surface enhancement group in ARTC is focusing on. Based on what you just said, I would presume that process digitalization is on the cards?

(!) C. C.: You are absolutely right. There are quite a number of things that we are working on, but for today, I would like to pick two of them to share. The first, as you said, is process digitalization, and the second is post-processing for additive manufacturing. For process digitalization, we have been at work developing a Digital Shot Peening platform. I believe many readers of MFN are familiar with shot peening, and would know that the process today is still largely manual, from process validation to coverage inspection. Digital Shot Peening aims to change the way that shot peening is done. It’s still too early to share the details, but fundamentally we are incorporating various sensors in the machine and using real-time readings to monitor and control the process instead. 

(?) MFN: That sounds really exciting, because shot peening has been essentially the same as it was decades ago. Following that thought, are you concerned that industry might be resistant to adopt this sort of revolutionary change to the process?

(!) C. C.: That’s a great question. We are happy to say that industry interest is very positive, especially the end users who face this problem on a daily basis. Last year, we did an early trial on a shopfloor with one of our industry partners, and the technicians were absolutely excited by what we did to their machine. 

(?) MFN: That’s excellent. As you know, many shot-peening practitioners read our magazine. You should definitely write an article for MFN to share more with our readers about this. 

(!) C. C.: I would be delighted to. To add on, although we are starting with Digital Shot Peening, our intention is to eventually do the same for other surface enhancement processes as well.

(?) MFN: Right, so that was on process digitalization. I believe the next item is related to additive manufacturing?

(!) C. C.: Yes, it’s on post-processing for additive manufacturing, or AM in short. Today, most people know that you get complex components, but post-processing remains a significant undertaking to prepare the part after it comes out from the AM machines. For metal AM components, which we focus on, the as-built surface roughness is poor. Although some applications can accept this, for many critical applications, they need to be polished. In ARTC, we have been steadfast on this for quite a few years now, and recently we are seeing quite a bit of traction in the industry in this field. In fact, one of the recent interviews in MFN was exclusively on this topic, if I am not wrong, with a subsidiary company of Rosler. 

(?) MFN: Yes, I see that you read our magazine religiously. Thank you! 

(!) C. C.: For sure! Anyway, our focus in ARTC has been mostly finishing inof the internal channel, where we use the abrasive flow- machining process, or AFM in short. AFM has been around for more than 50 years, but turns out there are quite a fewbit of tricks to get it right for AM parts. For example, you have to get the parameters right, otherwise the surface doesn’t smoothen no matter how long you run the process for. Other than that, we are also developing a process model and simulation that are meant for engineers to use. For AM components, it turns out you have to remove a significant amount of materials before the surface is polished. We think that it will be essential to consider this during the component design as well, hence the need for a simulation tool to predict these material removal distributions. 

(?) MFN: Let me ask this – are AM components more challenging to polish compared to conventional components?

(!) C. C.: Absolutely, and that is because of the relative freedom to introduce complex features into the components. On one hand, you have these complicated internal channels, which we hope the AFM process can address. With other complex features, other solutions are necessary, and quite a number of companies are coming out with very interesting solutions based on media finishing and electropolishing. In ARTC, we have done some work with the ‘flow’ finishing process for complex internal features, but we are looking to partner with industry to broaden our capabilities. Finally, one frontier that is still unsolved for now is the polishing of internal structures, such as lattices within a channel. It is something that the AFM process cannot accomplish, and we are doing some early works related to this in ARTC. 

(?) MFN: Thank you. That is a great overview of the key activities in your surface enhancement team. Let me just make sure I get them right – process digitalization and post-processing for AM. Did I get that right? 

(!) C. C.: Yes, you did. We don’t work on those two exclusively, and other works include fatigue enhancement and hybrid processes, but those two are definitely the bigger topics currently.

(?) MFN: Okay, I’m going to change direction to something that you have probably expected. How has COVID-19 impacted your work plan?

(!) C. C.: Yes, I’m glad that I have prepared for this question! Our day-to-day operation requires access to the shopfloor, so in the short term, COVID-19 is definitely going to delay project delivery. Beyond that, we are also anticipating a subdued appetite from industry to start new projects in the near term, though we don’t know to what extent at this point of time. That being said, I would like to shift gear here and share with you my thoughts on how it may create new opportunities in the longer term.

(?) MFN: Sure, let’s hear about that.

(!) C. C.: As a start, I am expecting a stronger push from the industry to accelerate towards process digitalization and automation. Now, this is especially interesting for us because a while ago we just said that process digitalization is and has been one of our main directions. Many surface enhancement processes – such as blasting, shot peening, and media finishing – are still manual in nature or require regular human supervision. With the disruption caused by COVID-19, we think that industry will be keen to accelerate efforts to digitalise and automate their processes in order to mitigate impact on business continuity when a similar episode occurs in the future. 

(?) MFN: Yes, we discussed digitalization earlier, but I notice that you tagged on automation to that as well. So, robots everywhere and people are not needed anymore?

(!) C. C.: That’s not true. In fact, when we speak of digitalization or automation, the first image that most people conjure is massive deployment of robots to substitute human activities. That may be true in mass production, but surface enhancement has complex processes and therefore robotics is not an instant solution. For a start, the expertise of technicians – which surface enhancement today heavily relies on – needs to be deconstructed and captured in some way. This means that process modelling and simulation will need to be developed in order to understand and predict the behaviour of these processes. Secondly, to empower these models, an array of sensors then needs to be introduced to the process to capture real-time data and also to make adjustment to the process when it makes sense to do so. In fact, this is what we are doing with Digital Shot Peening, which we briefly spoke about earlier.

(?) MFN: That’s an interesting take on automation. Let’s assume all these developments are successful and we now have these next-generation surface enhancement processes. You mentioned earlier that the practitioners were excited to see these technologies, but what does it mean for them when they actually work on these machines?

(!) C. C.: In my view, human expertise cannot be replaced completely, given how complex surface enhancement processes are. Therefore, we expect technicians and engineers to continue to play an important role, but they can expect more help from these intelligent systems. This help ranges from automated status reports, highlighting potential issues and possibly making suggestions for improvement. All these are not new and have been standard answers across the industry since the digitalization wave. Following COVID-19, an idea that we are toying with is whether it is feasible to develop tools that enable technicians and engineers to work remotely. And just to be clear, I’m not talking about Zoom meetings! Instead, the idea is that technicians and engineers can carry out some machine work remotely from home.

(?) MFN: If I were a practitioner, I wouldn’t mind running my machines from my couch at all, but I am not sure how that is going to work. As you said, surface enhancement has a complex workflow and I would think that it is difficult to work effectively if you are not by your machine.

(!) C. C.: The skepticism is understandable, and indeed we foresee quite a number of challenges to be addressed. At a high level, relaying commands to machines from home is technologically feasible, although there are minor challenges related to cybersecurity, connectivity and human interface design to be resolved. What we think are the major challenges boil down to two things. First, how do we extract high quality and timely information to allow someone working remotely to make a good decision? As an example, we visualize a collection of cameras that allow the remote technician to diagnose the process effectively. Secondly, once a decision has been made, the technician must have access to mechanisms to carry out his work effectively from a remote setting. Again, as an example, this could be a robot arm that the technician also controls remotely. Clearly there are limitations to this because some work requires flexible motions that cannot be done effectively when the technician is not at the machine. We are still at a very early stage at this, but it has been an interesting exercise so far.

(?) MFN: I will definitely look forward to hearing more about the progress of that in the future. Before we wrap up, I would like to quickly talk about the International Conference for Advanced Surface Enhancement (INCASE), which we co-organised last year. Can you tell our readers briefly what we can expect next?

(!) C. C.: We received very good feedback on the conference and the quality of work was amazing. The plan for the second edition of INCASE is already underway. We initially planned for Year 2021 to fit into the busy conference calendar, but with COVID-19 we are still evaluating our options. At this point, we can only promise it’s going to be even better than the first. We will share more information the soonest it is available.

(?) MFN: That’s great, and I think that will be all from me. Any final words before we wrap up?

(!) C. C.: Very quickly – if any of the readers find this interesting, please do not hesitate to drop me an email. We are always open to discussion and opportunities to collaborate with industry and academia alike.

(?) MFN: And that’s a wrap. Thank you, Dr. Wong, stay safe.

(!) C. C.: Thank you for having me, it has been fun. Stay safe too.

MFN would like to thank Dr. Wong Chow Cher for this interview!

For Information: 
Advanced Remanufacturing and
Technology Centre (ARTC)
3 Cleantech Loop, #01-01, CleanTech Two
Singapore 637143
Tel. +65.6715-6972
E-mail: wongcc@artc.a-star.edu.sg