The basic idea of today’s webinar is to describe what μ-MIM® is. Because many customers have asked us the differences between μ-MIM® and conventional MIM. Therefore, we select this as our 1st theme. I hope you get some news and valuable information to bring back to your company.
I will introduce our company first and then the technology. Those of you who know us long enough know that we were just Taisei Kogyo, which is here on this blue and white logo. Taisei Kogyo was established in the 1970s as a plastic injection moulding manufacturer. In the 1990s,
we expanded to MIM production, and then Taisei Kogyo is now focusing on MIM production as an OEM manufacturer. Micro MIM Japan Holdings (MMJH) was established as a parent company of Taisei Kogyo in 2017 and Micro MIM Japan is focusing on sales & marketing as well as R&D while Taisei Kogyo is focusing on manufacturing. Our headquarter is located in Osaka in Japan. We do MIM component production and some contracted analysis and measurement service. We accept some analysis and measurement of the parts that are not produced by us. We do that as a part of our normal procedure for outgoing measurement.
Apart from that we also have MIM feedstock sales. We are located in 3 countries. The Thailand factory is located in Pathumthani, which is north of Bangkok between Bangkok and Ayutthaya. I am in Offenburg, Germany which is about 1 hour from the Swiss border, and 20-30 minutes to the French border.
There are about 60 people in the group. Under the Taisei Kogyo factory, we are certified with ISO 13485 since about 50-60 % of our customers are in the medical device sector. This is why we switched from having ISO 9001 / 14001 to ISO13485 in 2019. For those who know MIM might be a bit boring with this slide, but Micro MIM is a metal powder metallurgy process focusing on precise production. First of all, we combine metal powder and binder. The question is which part we do in-house.
We purchase the metal powder and compose the feedstock in-house. We mix them and make them into pellets in the kneading & palletisation process. MIM pellets are just like the pellets for plastic injection if you have seen them. The pellets are put into an injection moulding machine, then we make the component like this for example. After the injection moulding, we do not want the binder inside anymore because, at the end, we want the metal part without any other material. Therefore, we put the injection moulded part, green part, into the debinding and sintering oven.
Some MIM companies have debinding furnaces and sintering furnaces separately. However, in our company, we do in 1 furnace for those 2 processes. Debinding is sometimes called degreasing as well. The brown part (after debinding part), in our case we do not see them at all. The final metal part is called sintered part or silver part.
In some cases, we might do some secondary processes. As you can see, it is shrinking from the green part to the sintered part. This shrinkage ratio varies depending on metal powder type, mixing ratio of the binder, metal powder particle size and so on. The technical overview of μ-MIM components We have registered this μ-MIM as our trademark in Japan. Compared to conventional MIM, these 3 areas are significantly different.
In the conventional MIM, the tolerance will achieve about +/-0.03 mm. But with our μ-MIM, the tolerance will achieve +/-0.01 mm if we use fine powder size of stainless steel. Same with relative density, in the conventional MIM, the average density is 95-98%, while our μ-MIM is 98.5% at minimum. The wall thickness, in the conventional MIM, about 0.3 mm (partially), while in μ-MIM, 0.1 mm and less is available
in case of the component is smaller than 5 mm square Surface roughness is another issue that many people are interested in. We are using powder size D50 of 3 μm which is the smallest in the market, and it achieves the Ra of 0.35 μm. The experienced materials including trial and serial production are shown.
In the MIM industry, μ-MIM covers a wider range of materials than competitors. This is since we produce the feedstock in-house. Therefore, we can control the material, we can create the material that is our own “recipe”.
It is required to prepare the powder ideal for MIM in terms of size, shape, etc. but we are open to join the R&D project with the customers to create a different alloy or try a new alloy. Now the components examples. Some of you have seen them. I haven’t been able to meet most of the customers, so for those who have not met us, I hope you will get some idea about what kind of parts are possible to produce by μ-MIM. I would like to mention that these are just some that we are allowed to show. We are producing a lot of medical device parts such as medical forceps.
There are so many varieties but of course for medical devices, we are not allowed to show. Medical forceps are often manufactured using metal and this particular one is disposable forceps. After each operation, they will be disposed.
Others are non-disposable, so you can select both types. Then we are making a lot of gears as you can see here. Some of the gears are a bit large for us but we have done them because they are not easy to produce with other manufacturing methods, especially in serial production. This is a part that has an inner curve structure with undercut. Usually, you cannot do this with conventional moulding technology.
We have a technology called 3D-μMIM technology that allows us to make such components. This is another example made by 3D-μMIM and the surface is cut so you can see the inside structure. Now another example that you might find interesting is the integration part. The customer asked us whether we can offer some solution for assembly cost and production time deduction with improving productivity. Then we came up with the idea to make them as 1 integrated component from the beginning. The customer could cut the production cost, even though they had to invest in the mould.
They cut the production cost significantly and lead time as well, so they were very happy with our solution. This integrated micro wheel is one of the very small component examples. Here the overall height is approximately 500 μm and the diameter is about 300 μm. This kind of exceedingly small size component serial production is also feasible.
The copper parts are here. These are pure copper then another example is a a copper alloy called nickel silver. Also, we do some other metal material, but the majority is stainless steel. This is a soft magnetic material This is a set of gears which is an integrated helical gear and tiny helical gear.
We do serial produce both the integrated helical gear and the small helical gear. It is quite nicely made without any visible parting lines. A lot of gears used in medical devices are helical because of the silent movement property. This is another helical gear, but this is an internal helical gear. The helical teeth are existing until the very end of the lid.
It's very difficult to manufacture this gear for serial production with machining. This kind of gear is ideal to use our μ-MIM technology. And for those who are not so familiar with MIM, those circles are ejection pin (EP) marks for demoulding. Of course, we can discuss the location of EP marks, parting line (PL) etc. in the DFM discussion. It is possible to change those EP and PL not show up in critical places.
This is a micro nozzle tip that has a 30 μm hole. These kinds of nozzles can be applied to medical devices as well as other industries. Perhaps some of you are wondering how we can make this micro hole with just the moulding technology. We are making this only with mould and this is the topic which we will have for the next series of our webinar. Now, 3D-μMIM, I mentioned earlier, I would like to introduce the details. The sacrificial plastic (SP) mould is made of plastic.
Then we over-mould the MIM feedstock, then we process the degreasing or debinding and sintering step. The binder and the SP mould are completely decomposed in the debinding and sintering process. When they come out from the furnace, you will just get the metal without plastic but with the internal structure. This 3D μ-MIM can be applied to the outside to give fine structure of the tiny part.
Now the latest news is that some of you might have read that we are having this 3D metal printer this summer. This is very good news for who are interested in doing a prototype phase but not finalise the serial production design yet. As you can see here the 3D metal printer is suitable for variety of design with small quantity production. We will be able to make the green part which is equivalent to the injection moulded part with this 3D printing machine. And then, we process the debinding and sintering step to produce the metal parts. Instead of tooling the proto type mould, this 3D metal printer will create the green part according to your design request.
The sintering condition will be the same as the serial production process, so you can evaluate your prototype parts. When you move to serial production, you can invest in the mould with the finalised design Thank you very much and I wish you a very nice evening and continue to have a nice week.
2021-10-17