Calculating Dimensional Drift in Precision Cast Aluminum Tooling Assemblies
Total assembly drift equals the vector sum of residual stress release, thermal creep, and joint slip, demanding empirical metrology validation after thermal soak.
Composite Tooling
Meaning
Specialized molds provide the shape and surface finish for components made from reinforced polymers. Because these parts are often cured at high temperatures, composite tooling must withstand repeated thermal cycles without losing its dimensional accuracy. Materials like carbon fiber or nickel-iron alloys are chosen for their low expansion rates.
Thermal Expansion
Matching the coefficient of expansion between the mold and the part prevents the formation of internal stresses. If composite tooling expands more than the laminate it holds, the finished component will be smaller than intended once it cools. Solid carbon molds offer the closest match for aerospace-grade pre-preg materials.
Surface Preparation
Application of release agents ensures that the cured part can be removed without damaging the mold or the product. High-quality composite tooling requires a polished surface to achieve the necessary aerodynamic or aesthetic finish on the outer skin. Vacuum integrity is also checked before each use to ensure no leaks exist during the curing process.
A leaky mold will result in a scrap part due to lack of consolidation pressure. Testing confirms the seal.
Lifecycle Durability
Repeated use in a production environment causes gradual wear on the mold edges and surfaces. Maintaining composite tooling involves regular inspections for micro-cracking or resin buildup.