Executive Summary
This guide is written for manufacturing engineers, procurement specialists, and program managers who are evaluating ceramic 3D printing as an alternative or complement to their existing investment casting supply chain. It provides a practical, step-by-step overview of how DDM Systems’ DirectPour™ process works, what information is needed to get started, and what to expect at each stage of engagement.
Whether you are exploring digital casting for rapid prototyping, legacy part replacement, or production-scale manufacturing, this guide will help you understand the process, prepare your data, and plan a successful pilot project.
Before You Start
DDM’s process begins with a digital model. The quality and completeness of your input data directly affects the speed and accuracy of the output.
What DDM Needs From You
Required
- CAD model of the desired part (STEP, IGES, or native CAD format). If no CAD exists, DDM can work from 3D scans and/or 2D engineering drawings to create one.
- Alloy specification: What material do you need the part cast in? DDM produces parts in hundreds of standard alloys.
- Quantity: Is this a single prototype, a short run, or a production program? DDM serves all volume levels.
Helpful but Not Required
- Dimensional tolerances and critical feature callouts
- Surface finish requirements
- Inspection and acceptance criteria (ASTM, customer specs)
- Previous casting history (if the part has been cast before, prior process data helps DDM optimize the new approach)
- Material certifications or test requirements
The DirectPour™ Process, Step by Step
Step 1. Design Review and Shell Engineering
Once DDM receives your CAD model and specifications, the engineering team reviews the design for casting feasibility. This includes evaluating wall thicknesses, internal passages, draft angles, and gating strategy.
DDM then designs the ceramic shell, including gating, risering, and any integrated cores. This is a critical engineering step that draws on decades of casting expertise to ensure a successful pour.
Step 2. Ceramic Shell Printing
The optimized shell design is printed on DDM’s LAMP™ production system. The printer deposits 100-micron layers of proprietary ceramic slurry and selectively cures each layer with UV light. Depending on part size and complexity, printing typically takes hours to a few days.
Step 3. Thermal Processing
After printing, the green ceramic shell undergoes thermal processing in two stages. First, the polymer binder is burned out at moderate temperature. Then the ceramic is sintered at high temperature to achieve full density and strength. The result is a monolithic ceramic shell ready for metal pouring.
Step 4. Metal Pouring
The finished ceramic shell is poured using standard investment casting techniques. DDM operates in-house pouring capabilities and also partners with established foundries (including Signicast, a subsidiary of Form Technologies) for high-volume and specialty alloy production.
Both air-melt and vacuum-melt processes are supported, enabling production of everything from aluminum and stainless steel to single-crystal nickel superalloys.
Step 5. Finishing and Inspection
Standard post-casting operations include shell removal, cut-off, grinding, and inspection. DDM castings are qualified to ASTM standards and Investment Casting Institute acceptability criteria. Additional NDT (radiography, FPI, dimensional inspection) can be performed as specified.
Timeline Expectations
One of the most significant advantages of DirectPour™ is the compression of lead time. The following table provides general timeline guidance for typical engagements.
| Phase | Typical Duration | Notes |
| Design Review | 1-3 days | Dependent on CAD completeness |
| Shell Engineering | 2-5 days | Includes gating and core design |
| Ceramic Shell Printing | 1-3 days | Dependent on part size/quantity |
| Thermal Processing | 2-3 days | Binder burnout + sintering |
| Metal Pouring | 1-3 days | Alloy dependent |
| Finishing and Inspection | 2-5 days | Per customer specifications |
| Total (Simple Part) | ~10 days | Compared to 52-80 weeks traditional |
| Total (Complex Part) | 4-6 weeks | Compared to 12-18 months traditional |
Available Materials
DDM produces castings in a broad range of alloys. The following represents currently qualified materials, with additional alloys available through standard foundry qualification processes.
| Alloy Family | Specific Alloys | Typical Applications |
| Stainless Steel | 304, 316, 17-4 PH, 15-5 PH, CF3M | Industrial, marine, food processing |
| Aluminum | A356, A357, A380 | Aerospace structures, automotive, hydraulics |
| Nickel (Air-Melt) | Inconel 625, Inconel 718 | Chemical processing, oil and gas |
| Nickel Superalloys | IN 713LC, MAR-M247, IN100 | Gas turbine components |
| DS Superalloys | René 141, René 80, René 142 | Turbine blades (directionally solidified) |
| Single Crystal | CMSX-4, René N5 | Advanced turbine airfoils |
| Medical | CoCrMo (ASTM F75) | Orthopedic implants |
| Tool Steel | S7 | Tooling inserts, wear components |
Planning Your Pilot Project
The most effective way to evaluate DDM’s capabilities is through a focused pilot project. Here is a recommended approach.
Selecting the Right Part
The ideal pilot part should demonstrate clear value from the digital casting approach. Good candidates include parts that are currently experiencing long lead times or supply chain disruptions, parts that require expensive or deteriorating tooling, parts with complex internal geometries that are difficult or expensive to produce conventionally, new designs where tooling has not yet been ordered, and legacy parts where original tooling has been lost.
Evaluating Results
When your pilot castings arrive, evaluate them using the same criteria you would apply to any investment casting. Dimensional inspection, chemistry verification, metallurgical evaluation, mechanical testing, and non-destructive testing should all be performed as appropriate for your application.
DDM castings meet ASTM standards and Investment Casting Institute stated ranges. The metallurgical quality, chemistry, and mechanical properties are consistent with production investment castings produced by conventional methods.
Conclusion
Digital investment casting is not a theoretical concept or a laboratory demonstration. It is a mature, production-ready manufacturing process that is delivering real parts to real customers across aerospace, defense, energy, automotive, medical, and industrial sectors today.
DDM Systems’ DirectPour™ process provides a clear, practical path from CAD file to finished casting, with lead times measured in days and weeks rather than months and years.
For the manufacturing engineer evaluating new supply chain options, the question is straightforward. Identify a part. Submit the CAD file. Receive a casting. Evaluate the results.