Metal injection molding outlook for 2022 in Europe

1. What is metal injection molding and when is it applied?

What is metal injection molding?

• During the last decades, MIM or “Metal Injection Moulding” has been confirmed as a very competitive technology for the manufacture of small steel parts of high precision and complexity, which would be very costly to produce by other processes.

• The feedstock is a material composed of very fine steel powder and a polymer that acts as a binder.

• This material can be injected into a metal mold as if it were a plastic, obtaining the “green piece”, which has the same shape as the piece we want to achieve, but is 20% larger in all its dimensions, since it still retains the plastic component.

• By attacking the green part with a catalyst, a phase called “debanding”, we cause the sublimation of the polymer, which is expelled in the form of gas. We call this the intermediate state, in which the part maintains its initial dimensions but is porous and has very low mechanical strength, “brown part”.  

• During the last phase of the process, the temperature is raised (always below the melting temperature of the steel) in a protective atmosphere, activating sintering by mass attraction. The part decreases in size as its density increases, reaching values above 97% for the final dimensions of the “MIM part”, which often coincides with the finished part.  

• Depending on technical requirements, MIM parts can be subjected to any type of subsequent treatments (thermal, surface, straightening, machining, polishing, welding, etc.).

• In 1993, ECRIMESA was the first company in history to develop this process in a continuous furnace, having at present 3 fully operational lines. Thanks to a wide range of automatic injectors with robotic handling systems that include artificial vision systems, high levels of productivity and quality are achieved.

When does it apply?

• Generally speaking, any part that can be manufactured by plastic injection molding could be produced in steel by MIM, but there are some limitations or rules to keep in mind:

• Although at ECRIMESA there are parts in production up to 350 grams (“record” of the technology, still in force worldwide), MIM is a recommended process for parts under 100 grams and especially competitive below 40 grams. The weight reduction increases the precision of dimensional tolerances and reduces raw material consumption, which has a great influence on the total cost.

• The maximum allowable radius is recommended for all edges, especially internal edges, since sharp edges can be sources of potential cracks.

• Section changes should be gradual, facilitating the flow of material during injection and avoiding isolated masses.

• A flat face will facilitate the palletizing of the part inside the MIM furnace. The more stable this support is, the smaller the deformations will be and the more precise the dimensional tolerances will be.

2. Sectors with the greatest development potential

• The main sectors acording to EMPA for the Metal Injection Moulding industry in Europe are focused on the automotive sector (22%) and the defense sector (19%) with a significant expansion during 2020.

• Ecrimesa Group confirms this general trend in the European market with a strong development of the defense, medical, tools and consumer goods sectors.

• EPMA forecasts for the coming years indicate growth in various sectors such as medical, automotive, defense, etc.

• From our company’s point of view, sectors such as defense and consumer goods will be critical in the evolution of the market in the coming years, and in the medium term we are very confident in the evolution of the medical and aerospace sectors in the European market for our MIM technology.

3. Main challenges of this technology for 2022 in Europe

• Even though we are facing a complex period strongly affected by the consequences of the pandemic generated by COVID-19, the rise in energy prices and transportation costs, the evolution of Metal Injection Moulding in Europe for the last half of 2021 looks positive.

• This is based on the data provided by the EPMA (European Powder Metallurgy Association), as well as the data we handle at Ecrimesa Group.

• The market evolution, according to the latest EPMA report, reflects a strong growth forecast for 2021.

• In our case, the forecasts estimated a rise in turnover for this year of more than 12% compared to 2019 sales, recovering the values of 2020, although in the first quarter these sales exceeded the forecasts by more than 25%, being expected for the first time in history to exceed 20 million Euros.

• In our opinion, the main difficulties facing European companies are:

1. Low development of MIM technology among designers, which means that there are not enough developments suitable for our technology and we have to collaborate in redesigns and in promoting the technology in design areas.
2. Competition with suppliers from “Low Cost” countries, although the weight of labor is not as critical in MIM as in other technologies, there is a difference in cost and fundamentally in the price of molds.
3. Competition with other productive technologies.

• In addition to these general points, which are repeated at the various congresses and meetings of the EPMA working groups, the Ecrimesa Group considers the supply of raw materials to be a major risk for 2022, given the growing demand and the situation of various suppliers of powder and feedstock in Europe and Asia, which could jeopardize the strong growth of the market.

• The challenges in the coming years that we see from Ecrimesa Group are: 

1. Complementarity of Additive Manufacturing technology with MIM technology in order to improve the time to market of MIM products and improve designers’ knowledge of both technologies to enable development in new industrial sectors.
2. Automation of production processes to improve competitiveness.
3. Digitalization of processes and application of Machine Learning and simulation technologies to strengthen processes.
4. Improvements in raw materials and development of new alloys for the medical, aerospace and automotive sectors.
5. Reduction of emissions generated by the production process Nox, CO2 and VOCs and of waste generated by the process.

4. Advantages of metal fabrication with MIM

• MIM is essentially a manufacturing technology for precision steel parts, with complex three-dimensional shapes, fine details, good aesthetics, demanding mechanical requirements and high consumption.

• It is colloquially known as “the enemy of machining”, because the tight geometric tolerances (±0.5%), low roughness (between Ra0.8 and Ra1.2) and high quality finish (possibility of including threads, knurling, logos, etc. in the mold) greatly reduce the need for second operations to obtain a finished part ready for the corresponding assembly line.   

• When the shape of the part in question allows it to be manufactured by traditional powder metallurgy (single shaft pressing + sintering), MIM may often appear uncompetitive. However, these types of parts are much more porous and fragile, so it is common for the application to force a switch to higher strength components such as MIM parts. 

5. MIM at Ecrimesa Group

• The main advantages offered by the Ecrimesa Group in this environment are focused:

1. Ability to develop new projects by having its own mold workshop with high production capacity and an experience of developing more than 2,000 projects in more than 40 different industrial sectors (allowing the internal maintenance of the molds, as well as speeding up modifications).
2. Development of R&D&I with investments of more than 200,000 Euros per year with support from the Ministry of Industry through the CDTI with collaborations with specialized centers such as DYPAM of the UCLM.
3. Important strategic alliances for many years with leading companies such as BASF, Arburg, Cremer, PolyMIM, Desktop Metal.
4. Our own heat treatment plant allows us to achieve high performance in low alloy steel parts (optimizing heat treatments to the size and microstructure of the MIM technology), which account for 75% of our production portfolio.
5. Machining plant that allows us to offer finished products to our customers, including surface treatments that are subcontracted.
6. Dimensional, metallurgical and materials laboratories with their own equipment (dimensional scanner, non-contact measurement, tomography and radioscopy, complete chemical analysis with elemental analyzers of % C, % O2, % N2, multibase spectrometers, TGA-DSC dilatometers, microhardness and optical microscopes with image analysis, mechanical and corrosion tests) that allow quality control, process improvement and undertake R&D projects and standardization of MIM materials.
7. Several batch and continuous sintering lines allow flexibility and high productivity.
8. CIM line that allows the development of supports for sintering while reducing deformations.

Discover our facilities for MIM!