6 Tips to Reduce Laser Powder Bed Fusion Costs

When it comes to conventional manufacturing, the general rule of thumb is that the more complex the part, the higher the costs. That’s not the case with additive manufacturing technologies such as laser powder bed fusion (LPBF).

Intricate designs with free-form surfaces, undercuts, or internal shapes aren’t the main price-driving factors. Instead, cost mostly comes from volume—the higher the price, the more metal powder is required in the design, directly impacting material costs.

Optimizing designs to minimize volume is essential to effectively lowering L-PBF costs. It’s also important to rethink the strategy for producing the part. Here are six ways to reduce costs.

1. Use Topology Optimization

Topology optimization uses algorithmic models to optimize the material layout within certain specifications. Those specifications can be related to symmetry, material properties, load conditions, etc.

In short, it’s an excellent technique to lower volumes and reduce the costs of metal additive manufacturing. Bound metal deposition, a specific technology used in certain metal 3D printers, has distinct cost implications due to its unique printing process and subsequent furnace processing.

Metal additive manufacturing can get expensive when large volumes are needed, so topology optimization software is well worth using when designing metal parts.

2. Design Lattices

A lattice is an interlaced structure of repeated patterns. Think of a honeycomb’s hexagons or a bridge’s crisscrossing beams. Within L-PBF, lattices are an excellent way to produce strong and lightweight parts. Lattices can be used instead of solid volume, resulting in significant cost savings. Designing lattices can be automated via CAD programs. It is relatively easy to print the structures through additive manufacturing – regardless of their complexity – as part of the printing process.

A solid cube vs. one with lattices

Topology optimization and lattices can be used together. Research shows that the two techniques are especially effective when combined. A 2019 study showed that using lattices and deploying topology optimization reduced costs by 54 percent. The weight of the part and the production time also dropped in half.

Want some more design insights? Check out the L-PBF design guide.

3. Fillet Corners

It’s usually good practice to fillet (round) all sharp edges in your design. One reason is that corners are where stress concentrations occur. Another reason is to reduce costs. Filleting outside edges results in slightly less metal powder and fewer metal particles used in the process. Filleting isn’t a massive cost reduction, but savings can increase over time. Plus, eliminating stress concentrations reduces the chance of part failure, which prevents unexpected cost overruns.

4. Understand the Different Metal Powder Types

Earlier in this guide, we mentioned how volume is one of the key drivers of price. Direct metal laser sintering (DMLS) uses specific metal powders to produce high-quality prints, particularly in medical applications. That’s true, but the metal powder type also affects the price. Depending on the project, certain metals will need to be used due to the various mechanical properties offered by each kind. Furthermore, powder variants combine metal types or provide different levels of purity.

Choosing the most affordable metal type with all the necessary mechanical properties helps reduce costs. Global metal prices fluctuate due to economic conditions, but here’s how the main metal types stack up in comparative prices.

5. Rethink Quantity

This isn’t a design tip but rather a strategic one. With additive manufacturing, producing smaller batches of units is significantly cheaper than conventional manufacturing. Metal printers, for instance, have specific operational costs, including the prices of powders and the overall expenses of running a metal 3D printing operation. That’s because additive manufacturing eliminates the need for tooling.

With the cost of tool design and tool production out of the equation, manufacturing costs per unit remain almost constant—as seen in the graph below. With the lower upfront costs and fast lead times, additive manufacturing has become especially popular for prototyping, tooling, jigs, fixtures, and on-demand end-use parts.

This graph also shows that as expensive as conventional manufacturing can initially be, the cost per unit drops when more units are produced. Your production numbers ensure that additive manufacturing is always the ideal technology. However, this chart shows it’s essential to know when that cost curve might shift in the other direction. When that’s about to happen, it’s best to be prepared and rethink the ideal production method for your project.

6. Get Near-Real-Time Prices on Iterations

Costs shouldn’t be a black box. When you’re experimenting with different materials, modified designs, and other factors, the last thing you want to do is wait around to see the impact on price. Fortunately, the days of sending a design and waiting for a manual quote are over. Atomic diffusion additive manufacturing, for instance, benefits greatly from real-time pricing updates, making it easier to produce cost-effective metal prototypes.

With MakerVerse, for example, you can upload a design and get an instant quote. Prices are immediately updated when you change the different materials, finishes, and more options. If you change the design, it can easily be re-uploaded for a new instant quote.

Next Steps

Additive manufacturing technology is constantly evolving. Selective laser melting (SLM) is one such evolving technology. Existing techniques continuously improve while completely new technologies are being developed. This means that additive manufacturing is never static. It’s a dynamic technology where staying on top of the latest trends is beneficial to finding price-optimizing opportunities.