3Dプリンターの種類とその機能は何ですか？

バインダー噴射は、良好な公差の部品を製造できますが、収縮は後処理で発生するため、最終的な公差を予測するのは難しい場合があります。

浸透する前は、金属部品は非常に弱く、注意深く取り扱わないと崩れる可能性があります。浸透後、それらは完全に高密度に近くなりますが、それらの機械的特性は、従来製造された部品のより高い品質を満たしていません。

これらの金属部品の表面粗さは、DMLSおよびSLMで達成されるものよりも優れています。

バインダージェット3D印刷は高速で費用効果が高いですか？

バインダー噴射は手頃な技術であり、バットの光重合やPBFよりもさらに低コストです。印刷速度はPBFに匹敵し、少量の印刷では他のテクノロジーと一致しますが、大量の印刷では高速です。

商用アプリケーション：バインダー噴射で何を生成できますか？

複雑な部品をさまざまな色で非常に迅速かつ費用効果の高い方法で製造できるため、バインダージェットはフルカラーのプロトタイピングに最適です。バインダー噴射の価格は材料噴射よりも低く、機械的特性の制限にもかかわらず、ほとんどのプロトタイプに適した解像度を達成できます。

これは、複雑で高精度の金属およびセラミック部品を製造するための最も高速で手頃な技術の1つでもあります。多くの異なる粉末が利用可能であり、プリントベッドは比較的大きくなる可能性があります。バインダージェット金属部品の機械的特性は、PBFプリントの強度や公差とは一致しませんが、浸透させて焼結した場合でも機能する可能性があります。

バインダージェットは、比較的低コストで大きく複雑な形状を印刷できるため、砂から複雑なキャストを作成する場合に特に魅力的です。また、このプロセスは、ほとんどの従来の鋳造プロセスと統合できるほど単純です。

直接エネルギー沈着とは何ですか？

直接エネルギー堆積（DED）は、通常は金属である溶融材料のビーズを層状にすることによって部品を製造します。この技術は、プラスチック材料の押し出しプリンターで使用されているものと非常に似ていますが、金属用です。粉末またはワイヤーのいずれかである原料は、ノズルを通して連続的に押し出され、堆積点でレーザーまたは電子ビームまたはアークによって溶融され、そこで冷却および固化されます。

ノズルは、ビルドプラットフォームに対して複数の軸に沿って移動できます。 3軸マシンは、x軸とy軸に沿ってプリントの単一の断面の形状をトレースし、z軸に沿って断面を重ねて、パーツ全体を構築します。 5軸DEDプリンターは、あらゆる角度から材料を堆積できるため、パーツをレイヤーごとに構築することに限定されません。つまり、パーツを最初から作成するだけでなく、既存のオブジェクトの複数の面に材料を堆積させるためによく使用されます。

DEDは、直接金属蒸着（DMD）と呼ばれることがよくあります。また、材料やエネルギー源が異なっていても、名前が同じ意味で使用されることが多い独自の技術も数多くあります。

すべてが非常に類似した原則に従って機能します。 OptomecによるLaserEngineeredNet Shaping（LENS）は、粉末を高出力レーザーと融合させる技術の最もよく知られた例です。 Sciakyによる電子ビーム積層造形（EBAM）は、押し出されたワイヤーを電子ビームと融合させる技術の最もよく知られた例です。

DEDプリンターの種類

LENSは、レーザーヘッド、粉末ディスペンシングノズル、および不活性ガスチューブで構成される蒸着ヘッドを利用します。レーザーはヘッドの中心を通過してビルドエリアにメルトプールを作成し、粉末は溶融して固化する側面からスプレーされます。不活性ガスは、酸素と水分を含まないシュラウドを形成し、表面の酸化を防ぎ、層の接着を促進します。

EBAM feeds metal welding wire through the nozzle and melts it with an electron beam at the contact point with the build area. Essentially, EBAM is FDM for metals.

Materials for DED

LENS technology can print in both metals and ceramics, although ceramics are by far the more common material in use. Available materials for both LENS and EBAM include almost any weldable metal, such as aluminum, steel, titanium, Inconel, tantalum, tungsten, nickel, and niobium.

Geometric properties of DED

Another key advantage of DED is the very large print bed sizes. It is not uncommon for large manufacturers to build customer DED printers with build envelopes that are multiple meters long along any dimension.

Support structures are possible but difficult because the large liquid melt pool at the deposition point does not allow for overhangs. The same attribute means complex geometries are also not possible. Resolution is very poor compared with other metal 3D printers. Powder particle sizes are between 50 and 150 microns and welding wire ranges from 1 to 3mm in diameter.

Sharp corners, for example, can only be achieved in post-processing, typically by a CNC mill. This is very common practice, as new material is built up with DED and then machined to the desired precision.

Mechanical properties of DED

The high amount of energy required to maintain a melting point at the point of deposition creates large thermal gradients that can cause a lot of residual stress, but DED produces fully dense parts with mechanical properties that are as good as forged metal parts.

The low resolution, however, means parts tend to have a poor surface finish, requiring secondary machining to achieve the most desired results.

Is DED fast and cost-efficient?

The two most important advantages of DED are print speed and material cost. All DED technologies are relatively fast at laying down material, with the fastest machines printing 11kg per hour, (albeit with very low resolution). The metal feedstock used is also cheaper than that used by other metal 3D printers.

The powders are usually commercial off-the-shelf (COTS) materials designed for welding and are widely available. But for simple parts, traditional manufacturing is still almost always cheaper.

Commercial applications:what can you produce with DED?

The three main applications of DED are part repairs, feature additions, and near-net-shape part production. Essentially a form of welding, DED can print onto existing parts. This makes it ideal for repairing broken parts and adding features that cannot be added via other processes. Tool repair is by far the most common use, and companies turn to DED when expensive machinery proves more cost-effective to fix than reorder, such as in heavy industry.

Because the resolutions are so low, most parts also require post-processing with a CNC mill. Parts are therefore printed near to net shape, with the expectation that they will be machined to proper tolerances. Because conventional manufacturing is almost always cheaper, near-net-shape DED printing is only used when traditional manufacturing is very slow, expensive, or simply not possible.

What is sheet lamination and how does it work?

Sheet lamination produces parts by stacking and laminating sheets of material cut to match a part’s single-horizontal cross-sections. In some printers, the sheets are first cut and then laminated. In most, the sheets are first laid and laminated and then cut to size.

Types of sheet lamination printers

This is one of the simplest methods of building up 3D models. Despite its simplicity, there are many different proprietary technologies based on material, lamination method, and cutting method. In most cases, the process is a simple variation of paper laminated object manufacturing (LOM). Ultrasonic consolidation (UC) is the only radically different technology, as it uses ultrasonic welding rather than a separate bonding agent.

• LOM laminates sheets together with a bonding adhesive and then subtracts features layer by layer, using CNC milling, laser cutting, or water-jet cutting.

• UC follows the same process at LOM, except the lamination is achieved through ultrasonic vibrations as a form of friction welding.
  

Materials for sheet lamination

Across all the different types of printers, there are many available materials:papers, most polymers, fiber-reinforced polymers, ceramics, and just about any metal. Multi-material layers can also be achieved with all these materials, provided each layer can be laminated and shaped with the same methods.

Using colored sheets enables full-color prints across the color spectrum.

Geometrics properties of sheet lamination

Sheet lamination print beds vary quite a lot in size, but are comparable to SLA and SLS printers. Large-format printers are not common.

Because the sheet cutting methods are relatively simple, highly complex shapes are not possible. However, because support structures are not necessary, internal structures are possible.

One additional design option is to lay embedded wiring between sheets. Most processes do not require heat, so expect a reduced risk of high temperatures destroying them. Typical layer resolution depends entirely on the material feedstock

Mechanical properties of sheet lamination

Dimensional accuracy and surface finishes are on par with what can be achieved with a simple CNC milling machine, laser cutter, or water-jet cutter. The weakness of the bond between sheets, however, means that these parts are unsuitable for structural or functional purposes.

Is sheet lamination fast and cost-efficient?

LOM is very cost-effective thanks to the ready availability of all the raw materials. The lack of pre-production preparation means the printers are also very fast.

What are the commercial applications of sheet lamination?

LOM was originally used in architecture for building models. Today its most common use is for highly detailed, colored objects, typically for proof-of-concept and look-and-feel prototyping.

Frequently asked questions

How do I decide the right 3D printing technology for my custom parts?

There are many factors to think about before settling on the right 3D printer for your manufacturing needs. These include functionality, materials required, cosmetic characteristics, process capabilities and many more. To start, check out this comprehensive resource on selecting the right 3D printing process, and remember that you can (and should) always test different printing methods before finding the one that's perfect for your custom parts.

What 3D printer is optimal for complex geometries.

For designs with complex geometries, we highly recommend opting for a powder bed fusion technology like SLS or MJF.

What do I do if several 3D printers work for my custom parts?

Oftentimes, several different 3D printing processes can produce your parts. If this ends up being the case, compare the cost and properties of each to determine the right manufacturing fit.

What 3D printing technology is right for functional polymer parts?

For functional polymer parts, go for thermoplastics ( SLS or FDM) over thermosets (SLA/DLP or material jetting).

What 3D printing technologies will give me the best cosmetic appearance?

For the best cosmetic quality, thermosets (SLA/DLP or material jetting) will give you the most impressive aesthetics.

What's the best 3D printing technology for metal parts?

Honestly, we recommend pivoting to CNC machining for producing metal parts, though if your designs are very complex, DMLS and SLM are viable alternatives to milling and turning.