Bagaimana Kuasikristal Memperkuat Aluminium 3D-Printed Kelas Dirgantara

Dari Teori ke Praktik

Sometimes, Nobel Prize attribution goes to research that might be a little abstract for the greater public. This was the case for Penghargaan Nobel 2011 dalam Kimia, yang memberi penghargaan atas penemuan “quasicrystals”.

Ini karena banyak material di alam, maupun yang dibuat manusia, tersusun dalam kristal “normal”. Apa yang mendefinisikannya adalah struktur 3D sederhana pada tingkat atom yang berulang jutaan kali, hingga skala makroskopik. Struktur‑struktur ini yang memberikan sifat pada berbagai logam, serta material lain seperti silikon yang masuk ke dalam chip komputer dan panel surya.

Ada hanya 230 cara yang mungkin bagi atom untuk membentuk pola kristal berulang, sesuatu yang sebelumnya dianggap sebagai aturan kaku alam.

Sumber: Nobel Prize

Namun, ternyata struktur lain juga memungkinkan, di mana beberapa bentuk dasar dapat dirakit menjadi struktur molekul reguler, sekaligus tidak memiliki pola berulang. Penemuan ini dibuat oleh seorang peneliti yang sebagian besar bekerja di National Institute of Standards and Technology (NIST).

Sumber: NIST

Andrew Iams, seorang peneliti di NIST, mungkin telah menemukan aplikasi praktis untuk kuasikristal semacam itu, karena mereka terbentuk selama pencetakan 3D aluminium. Karena aluminium adalah logam yang sangat berguna dalam aplikasi dirgantara, namun juga secara signifikan sulit untuk dicetak 3D, hal ini dapat menjadi terobosan besar.

(Anda dapat membaca ikhtisar industri pencetakan 3D dalam artikel kami “3D Printing Consolidating Into The Future Of Manufacturing”.

These results¹, performed by researchers at the NIST, HRL Laboratories LLC, and L.A. Giannuzzi & Associates LLC, were published in the Journal of Alloys and Compounds, under the title “Microstructural features and metastable phase formation in a high-strength aluminum alloy fabricated using additive manufacturing”.

Mengapa Kristal Penting?

While a crystalline structure can give special properties to a material, it also comes with weaknesses.

Karena strukturnya sangat teratur, atom dapat dengan mudah meluncur melewati satu sama lain. Ketika terjadi pada skala besar, hal ini menciptakan mikroretakan atau bahkan retakan besar pada material, secara keseluruhan membuatnya lebih lemah daripada yang secara teoritis mungkin.

Masalah ini semakin besar pada pencetakan 3D karena logam meleleh dalam jumlah kecil dan kemudian didinginkan berkali‑kali. Dan untuk pencetakan 3D maupun penempaan tradisional, aluminium khususnya rentan terhadap apa yang disebut retakan solidifikasi, atau “hot tearing”.

This happens when the remaining liquid metal fails to compensate for the contraction of the cooling, already solid metal. Such cracks compromise the structural integrity of the aluminum parts, potentially leading to weaker materials that are more prone to failure.

Kebutuhan untuk Pencetakan 3D Aluminium yang Lebih Baik

Suhu yang Jauh Lebih Ekstrem

When casting in aluminum in the traditional way, the liquid metal temperatures range between 690 °C to 725 °C (1274 °F – 1337 °F), and solidification cooling rates typically between 0.4 °C/s to 10 °C/s.

In contrast, additive manufacturing (3D printing) for metallic materials uses laser-powder bed fusion, where metal powder is deposited and then melted by a laser (follow the link to see it in video).

This generates liquid metal temperatures beyond 3000 °C (5430 °F), past the metal boiling point instead of just melting it, and ultra-fast solidification cooling rates exceeding 1 million °C/s.

These higher temperatures and much higher cooling speeds magnify the problem of solidification cracks.

“High-strength aluminum alloys are almost impossible to print. They tend to develop cracks, which make them unusable.”

Fan Zhang – NIST physicist

Janji Aluminium Cetak 3D

Despite the technical difficulties, 3D printing aluminum is very promising, as it can create shapes and parts that other forging techniques could not create.

For example, parts of rocket engines or fuel nozzles for airplane engines are now often made with 3D printing, turning up to 20 parts needing assembly into just one and reducing its weight.

In 2017, a team of HRL Laboratories (who contributed to the research discussed here) discovered that adding zirconium to the aluminum powder prevented the 3D-printed parts from cracking, resulting in a strong alloy.

Sumber: Journal of Alloys and Compounds

However, why this works was still pretty much not understood until strange structures were observed in the atomic metal structure.

“In order to trust this new metal enough to use in critical components such as military aircraft parts, we need a deep understanding of how the atoms fit together.”

Fan Zhang – NIST physicist

Menemukan dan Membuat Kuasikristal

The researchers had to use an electron microscope to analyze the material at the smallest possible image resolution. It reveals that the atoms were arranged in novel, strange patterns exhibiting fivefold, threefold, and twofold rotational symmetry that could not be caused by the crystals normally found in aluminum alloy.

“That’s when I started to get excited. Because I thought I might be looking at a quasicrystal.”

Andrew Iams, materials research engineer at NIST

Besides the areas with fine grains of aluminum-zircon alloy, the researchers observed icosahedral quasicrystals, in the shape of 20 sides dice.

Sumber: Math Stack Exchange

This breaks the regular crystal structure normally found, reducing the potential for cracks to form. So quasicrystals break up the regular pattern of the aluminum crystals, causing defects that make the metal stronger.

Sumber: Journal of Alloys and Compounds

Computer simulation then provided insights into the formation of the quasicrystals. It appeared that there is a secondary phase during the cooling process, which is favorable to quasicrystal formation.

From cores made of quasicrystal, ramifications of quasicrystal line break patterns in the metal, making it overall stronger and less likely to crack during cooling or under mechanical stress.

Sumber: NIST

Pengembangan Masa Depan

This new type of 3D printed aluminum alloy displays a hardness comparable to peak-aged AA7075, an established aluminum alloy with high resistance to corrosion and extensively used in aircraft structural parts.

These initial tests suggest that precipitation-hardening heat treatment could make this alloy even harder, although it still needs to be proven experimentally.

It also creates a framework in which the production of even stronger aluminum could be possible. Now that material scientists can partially predict the formation of quasicrystals during additive manufacturing, they could focus on improving their occurrence to enhance mechanical performance.

Berinvestasi dalam Pencetakan 3D

3D printing is only now reaching technological maturity, as well as market consolidation. This gives investors a little more visibility than in the past and confirms that this technology is far from a fad but is here to stay.

You can invest in 3D-printing-related companies through many brokers, and you can find on this website our recommendations for the best brokers in the USA, Canada, Australia, the UK, as well as many other countries.

Besides the companies discussed below, you can also find potential investing ideas in our article “Top 10 Nanotechnology Stocks”.

If you are not interested in picking specific 3D printing companies, you can also look into ETFs like ARK Invest 3D Printing ETF (PRNT) to capitalize on the growth of the additive manufacturing sector as a whole.

Contoh Inovatif

(Besides the companies discussed below, you can read about others in our article “Top 10 Additive Manufacturing And 3D Printing Stock to Watch”)

Nano Dimension

Most additive manufacturing companies focus on metal and plastic, with an eye for complex mechanical parts. Nano Dimension (NNDM ) was instead focused on 3D-printed electronics. This includes very specialized technologies like conductive or dielectric inks & ceramics. These can for example be used for building optical or radio components.

This is one of the possible applications of 3D printing to the nanoscale, which we explored further in “Nanoscale 3D Printing Looks Primed for Commercialization”.

Nano Dimension has grown through a mix of acquisitions and internal R&D.

Sumber: Nano Dimensions

This strategy reached a new high with the acquisition of Desktop Metal announced in 2024  and finalized in 2025. Together, the 2 companies will have a much stronger position in metal and ceramics 3D printing at all scales, from electronics to large industrial equipment and aerospace.

This also creates economies of scale by merging the customer base that includes SpaceX (SPCX ), Tesla (TSLA ), GE, Honeywell, Emerson, Raytheon, NASA, Medtronics, etc.

Lastly, the two companies were mostly active in different geographic areas, with Nano Dimension in Europe and Desktop Metal in the US, allowing for synergy by merging their sales teams.

Sumber: Nano Dimension

The company claims it can reduce the ecological footprint of manufacturing, with a reduction of 94% in CO2 emissions, 100% in water, 98% in materials, and 82% in chemicals. Overall, we can expect Nano Dimension to emerge as one of the technology’s leaders.

Sumber: Nano Dimensions

The merged companies are very well positioned to leverage new discoveries in 3D printing and how to make a stronger aluminum alloy, with these innovations likely to expand the addressable market.

However, investors need to be aware that both per-acquisition Nano Dimension and per-acquisition Desktop Metal were cash flow negative, so the resulting company will need to cut costs or grow sufficiently to turn a profit in the future.

Terbaru tentang Nano Dimension

Studi yang Dirujuk:

^{1. Andrew D. Iamset al. (2025). Rapid manufacturing of high-permittivity dielectric elastomer actuator fibers. Journal of Alloys and Compounds. Volume 1025, 25 April 2025, 180281. https://doi.org/10.1016/j.jallcom.2025.180281}