Manufacturing

Metalphoto also referred to as photo anodized aluminum utilizes the porous nature of unsealed anodized aluminum to create a sub-surface image, either through exposure and development of an anodic layer impregnated with silver compounds, much like traditional black & white photography, or through use of a photomask  in which the image is created through a variety of means, including chemical etching, color addition or color subtraction.

Type 1 photosensitive anodized aluminum is anodized aluminum that has been impregnated with a silver compound which, when exposed to a light source, creates an activated latent image. Upon development and fixing a black, silver-based image is formed inside of the metal. Type 1 photosensitive anodized aluminum is then sealed in boiling water similarly to common anodized aluminum. Sealing hydrates the aluminum oxide surface,[8] trapping the image beneath the anodized layer. The combined benefits of UV stability and the high image resolution of silver photography along with the abrasion and corrosion resistance of anodized aluminum are used to advantage in applications where permanent product identification is critical such as equipment nameplates, IUID barcode labels, outdoor signage, safety/warning plates, machine control panels and fine art.

Type 2 photosensitive anodized aluminum is typically coated with a photo resist, which may be of either the positive or negative type. Exposure of the photo resist through a negative and its

subsequent development creates areas on the plate that are either protected by the resist or exposed to the effects of the dye, bleach, or etchant that are used to create the contrasting mark. Common use for Type 2 applications are those where color (other than black) is desired on the finished product. The dyes used to create colored Type 2 plates can vary significantly in their heat and color fastness, so are often limited to indoor or short-term outdoor usage. Note that colored dyes can also be incorporated into Type 1 photosensitive anodized aluminum.

Metalphoto’s archival, silver-halide based image is sealed inside of anodized aluminum, making it readable after prolonged exposure to a variety of harsh operating conditions including weather/sunlight, heat, abrasion, chemicals and salt-spray.

The benefit is fewer label, nameplate, sign or control panel replacements due to illegibility – that means guaranteed regulatory compliance, asset identification and brand representation.

The benefits of photographic resolution are three-fold:

Your label, nameplate or panel will always look crisp and clear – conveying a sense of quality and reliability that will distinguish your brand.

High-resolution images make it possible to mark small items or surfaces such as firearms or others where a large label is not feasible.

Optional security printing features such as micro-text and watermarks that verify the authenticity of your product and protect it against fraud and counterfeiting.

Laser engraving is the practice of using lasers to engrave an object.The technique does not involve the use of inks, nor does it involve tool bits which contact the engraving surface and wear out, giving it an advantage over alternative engraving or marking technologies where inks or bit heads have to be replaced regularly.

A laser engraving machine consists of three main parts: a laser, a controller, and a surface. The laser is a drawing tool: the beam emitted from it allows the controller to trace patterns onto the surface. The controller determines the direction, intensity, speed of movement, and spread of the laser beam aimed at the surface. The surface is chosen to match the type of material the laser can act on.

HOW DO LASER ETCHING AND ENGRAVING WORK?

To create permanent marks, laser etching and engraving processes start with a beam of concentrated light energy.

The laser beam targets a small area of the material, known as the focal point.

The heat generated by the light energy allows the laser machine to alter the material’s surface, while the focal point ensures it affects only a specified part of the surface.

The result is a smooth, high-contrast, lasting mark, which can be human readable (serial number) or machine readable (barcode), etched or engraved into the part’s surface.

In the laser etching process, this mark will reach a depth of about 0.0001 inches. In the laser engraving process, the mark depth is typically up to 0.005 inches.

A subset of this process, known as deep laser engraving, is characterized by a mark that is greater than 0.005 inches deep. These marks are extremely durable and beneficial for industries where marks need to withstand harsh conditions.

There is also a range of industrial applications where manufacturers can use laser etching and engraving to mark the following:

• Logos
• Name Plates
• Metal Labels
• Date or time stamps
• Serial numbers Tags
• Barcodes Labels
• Metal Tags

Laser cutting is mainly a process in which a focused laser beam is used to melt material in a localised area. A co-axial gas jet is used to eject the molten material and create a kerf. A continuous cut is produced by moving the laser beam or workpiece under CNC control. There are three major varieties of laser cutting: fusion cutting, flame cutting and remote cutting.

In fusion cutting, an inert gas (typically nitrogen) is used to expel molten material out of the kerf. Nitrogen gas does not exothermically react with the molten material and thus does not contribute to the energy input.

In flame cutting, oxygen is used as the assist gas. In addition to exerting mechanical force on the molten material, this creates an exothermic reaction which increases the energy input to the process.

In remote cutting, the material is partially evaporated (ablated) by a high-intensity laser beam, allowing thin sheets to be cut with no assist gas.

The laser cutting process lends itself to automation with offline CAD/CAM systems controlling either three-axis flatbed systems or six-axis robots for three-dimensional laser cutting.

Machine Configurations

There are generally three different configurations of industrial laser cutting machines: moving material, hybrid, and flying optics systems. These refer to the way that the laser beam is moved over the material to be cut or processed. For all of these, the axes of motion are typically designated X and Y axis. If the cutting head may be controlled, it is designated as the Z-axis.

Moving material lasers have a stationary cutting head and move the material under it. This method provides a constant distance from the laser generator to the workpiece and a single point from which to remove cutting effluent. It requires fewer optics, but requires moving the workpiece. This style machine tends to have the fewest beam delivery optics, but also tends to be the slowest.

Hybrid lasers provide a table which moves in one axis (usually the X-axis) and move the head along the shorter (Y) axis. This results in a more constant beam delivery path length than a flying optic machine and may permit a simpler beam delivery system. This can result in reduced power loss in the delivery system and more capacity per watt than flying optics machines.

Flying optics lasers feature a stationary table and a cutting head (with laser beam) that moves over the workpiece in both of the horizontal dimensions. Flying optics cutters keep the workpiece stationary during processing and often do not require material clamping. The moving mass is constant, so dynamics are not affected by varying size of the workpiece. Flying optics machines are the fastest type, which is advantageous when cutting thinner workpieces.

Flying optic machines must use some method to take into account the changing beam length from near field (close to resonator) cutting to far field (far away from resonator) cutting. Common methods for controlling this include collimation, adaptive optics or the use of a constant beam length axis.

Five and six-axis machines also permit cutting formed workpieces. In addition, there are various methods of orienting the laser beam to a shaped workpiece, maintaining a proper focus distance and nozzle standoff, etc.

Laser technology has the following advantages:

• High accuracy
• Excellent cut quality
• High processing speed
• Small kerf
• Very small heat-affected zone compared to other thermal cutting processes
• Very low application of heat, therefore minimum shrinkage of the cut material
• It is possible to cut complex geometrical shapes, small holes, and beveled parts
• Cutting and marking with the same tool
• Cuts many types of materials
• No contact between the material and machining tool (focusing head) and therefore no force is applied to the work-piece
• Easy and fast control of the laser power over a wide range (1-100%) enables a power reduction on tight or narrow curves
• The oxide layer is very thin and easily removed with laser torch cutting
• High-pressure laser cutting with nitrogen enables oxide-free cutting

3D printing is also known as additive manufacturing, therefore the numerous available 3D printing process tend to be additive in nature with a few key differences in the technologies and the materials used in this process.

A large number of additive processes are now available. The main differences between processes are in the way layers are deposited to create parts and in the materials that are used. Some methods melt or soften the material to produce the layers, for example. selective laser melting (SLM) or direct metal laser sintering (DMLS), selective laser sintering (SLS), fused deposition modelling (FDM), or fused filament fabrication (FFF), while others cure liquid materials using different sophisticated technologies, such as stereo lithography (SLA). With laminated object manufacturing (LOM), thin layers are cut to shape and joined together (e.g., paper, polymer, metal). Particle Deposition using inkjet technology prints layers of material in the form of individual drops. Each drop of Solid Ink from Hot-melt material actually prints one particle or one object. Colour Hot-melt inks print individual drops of CMYK on top of each other to produce a single colour object with 1-3 layers melted together. Complex 3D models are printed with many overlapping drops fused together into layers as defined by the sliced CAD file. Inkjet technology allows 3D models to be solid or open cell structures as defined by the 3D printer inkjet print configuration. Each method has its own advantages and drawbacks, which is why some companies offer a choice of powder and polymer for the material used to build the object. Others sometimes use standard, off-the-shelf business paper as the build material to produce a durable prototype. The main considerations in choosing a machine are generally speed, costs of the 3D printer, of the printed prototype, choice and cost of the materials, and colour capabilities.

Polymer 3D Printing Processes

Let’s outline some common plastic 3D printing processes and discuss when each provides the most value to product developers, engineers, and designers.

Stereolithography (SLA)

Stereolithography (SLA) is the original industrial 3D printing process. SLA printers excels at producing parts with high levels of detail, smooth surface finishes, and tight tolerances. The quality surface finishes on SLA parts, not only look nice, but can aid in the part’s function—testing the fit of an assembly, for example. It’s widely used in the medical industry and common applications include anatomical models and microfluidics. We use Vipers, ProJets, and iPros 3D printers manufactured by 3D Systems for SLA parts.

Selective Laser Sintering (SLS)

Selective laser sintering (SLS) melts together nylon-based powders into solid plastic. Since SLS parts are made from real thermoplastic material, they are durable, suitable for functional testing, and can support living hinges and snap-fits. In comparison to SL, parts are stronger, but have rougher surface finishes. SLS doesn’t require support structures so the whole build platform can be utilized to nest multiple parts into a single build—making it suitable for part quantities higher than other 3D printing processes. Many SLS parts are used to prototype designs that will one day be injection-molded. For our SLS printers, we use sPro140 machines developed by 3D systems.

PolyJet

PolyJet is another plastic 3D printing process, but there’s a twist. It can fabricate parts with multiple properties such as colors and materials. Designers can leverage the technology for prototyping elastomeric or overmolded parts. If your design is a single, rigid plastic, we recommend sticking with SL or SLS—it’s more economical. But if you’re prototyping an overmolding or silicone rubber design, PolyJet can save you from the need to invest in tooling early in the development cycle. This can help you iterate and validate your design faster and save you money.

Digital Light Processing (DLP)

Digital light processing is similar to SLA in that it cures liquid resin using light. The primary difference between the two technologies is that DLP uses a digital light projector screen whereas SLA uses a UV laser. This means DLP 3D printers can image an entire layer of the build all at once, resulting in faster build speeds. While frequently used for rapid prototyping, the higher throughput of DLP printing makes it suitable for low-volume production runs of plastic parts.

Multi Jet Fusion (MJF)

Similar to SLS, Multi Jet Fusion also builds functional parts from nylon powder. Rather than using a laser to sinter the powder, MJF uses an inkjet array to apply fusing agents to the bed of nylon powder. Then a heating element passes over the bed to fuse each layer. This results in more consistent mechanical properties compared to SLS as well as improved surface finish. Another benefit of the MJF process is the accelerated build time, which leads to lower production costs.

Fused Deposition Modeling (FDM)

Fused deposition modeling (FDM) is a common desktop 3D printing technology for plastic parts. An FDM printer functions by extruding a plastic filament layer-by-layer onto the build platform. It’s a cost-effective and quick method for producing physical models. There are some instances when FDM can be used for functional testing but the technology is limited due to parts having relatively rough surface finishes and lacking strength.

Metal 3D Printing Processes

Direct Metal Laser Sintering (DMLS)
Metal 3D printing opens up new possibilities for metal part design. The process we use at Protolabs to 3D print metal parts is direct metal laser sintering (DMLS). It’s often used to reduce metal, multi-part assemblies into a single component or lightweight parts with internal channels or hollowed out features. DMLS is viable for both prototyping and production since parts are as dense as those produced with traditional metal manufacturing methods like machining or casting. Creating metal components with complex geometries also makes it suitable for medical applications where a part design must mimic an organic structure.

Electron Beam Melting (EBM)

Electron beam melting is another metal 3D printing technology that uses an electron beam that’s controlled by electromagnetic coils to melt the metal powder. The printing bed is heated up and in vacuum conditions during the build. The temperature that the material is heated to is determined by the material in use.

The industrial applications of 3D printing services

3D printers change the entire manufacturing process, and many companies have adopted this manufacturing technology.

Here are some of the industrial applications of 3D printing services:

Drone

The 3D printing allows drone manufacturers to create a customized drone where every assembly part except electronic components can be 3D printed. The 3D technology enables the easy production of accessories such as cases, coverings, mounts, and boosters that facilitate proper drone storage. The additive manufacturing process helps to create lightweight and faster drones of different sizes at less cost.

Aerospace & defense

The Aerospace & defense industry has been benefited from 3D printing since they manufacture functional parts used in aircraft, which include wall panels, air ducts, and structural metal components etc. The primary advantage of using 3D printing in aerospace is weight reduction which significantly decreases payload, fuel consumption, and carbon dioxide emissions. Plus, it allows material efficiency, part consolidation, and low-volume production.

Robots

3D printing capabilities allow robotic parts to be manufactured quickly and straightforwardly. Factors such as reduced weight and customizability play a vital role in robot parts production like in sensor mounts and grippers, which require customization for various uses as they are costly to fabricate. Many robotics companies use Markforged 3D printers in designing and fabricating lightweight and complex parts like end-of-arm tooling at a lower cost.

Automotive

Many automotive industries are using 3D printers in areas such as performance racing and motorsports. Automotive manufacturers print different parts using 3D printers. These include cradles, fixtures, and prototypes that are sturdy, stiff, and long-lasting. The key advantages are greater design flexibility, customization, and faster product development. Additionally 3D printing helps create intricate geometrics such as internal channels, fine mesh, and thin walls.

Medical & dental

3D printing is heavily used in the medical & dental industry, from bio-printing to prosthetics and medical devices. 3D printing applications in the medical sector are very versatile; for instance, CT scanning offers different patient-specific solutions like dental appliances and implants, other benefits enhanced medical devices and personalized healthcare.