The Near-Net-Shape Advantage
Superalloy raw materials cost $30 to $100+ per pound depending on the specific alloy and form. When components are machined from wrought bar or billet stock, 60 to 90 percent of this expensive material may be converted to chips—material that has been purchased, melted, and processed only to be cut away and recycled at a fraction of its original value. Near-net-shape (NNS) investment casting dramatically reduces this waste by producing components whose as-cast geometry closely approximates the final part, with only critical surfaces requiring machining. For complex components in high-cost alloys, NNS casting can reduce total component cost by 30 to 60 percent compared to machining from solid stock.
How Close Is Near-Net-Shape
CastAlloy's investment casting process achieves dimensional accuracy of plus or minus 0.010 inches for the first inch, plus 0.003 inches per additional inch. Wall thicknesses as thin as 0.030 inches are achievable. Surface finishes of 125 Ra microinches or better are standard in the as-cast condition. These capabilities mean that many non-critical surfaces require no post-casting machining at all, while critical interfaces, sealing surfaces, and bearing fits are machined to final tolerances from minimal stock allowances (typically 0.020 to 0.060 inches per side).
When to Choose NNS Casting
Near-net-shape casting provides the greatest cost benefit for components with complex geometries that would require extensive multi-axis machining, parts in high-cost alloys where material savings are significant, moderate to high production volumes where tooling investment is amortized, and components with internal features (passages, cavities) that cannot be machined. CastAlloy's engineering team can evaluate your component and provide a cost comparison between NNS casting and machining from solid. Request a consultation to explore the cost savings.