By: Dave Olsen
Hot forming and superplastic forming dies are a tool used to form a material to a desired shape. This tool or die is usually made from specialized metals including H-Series stainless steel, Invar, or Inconel. Like most metal components, there are various ways to manufacture forming dies, including the sand casting and centrifugal casting processes.
Here are just a few examples of when the metal casting process solved a customer’s tooling problem in the aerospace market.
1.) Sand Casting Process Solved Problem With Hot Forming and Super-Plastic Tooling Cracking Due To Thermal Cycles
A major supplier of aerospace components that designs and purchases tooling for hot forming and super-plastic forming of Inconel and Titanium aerospace components came to MetalTek for help. The supplier was experiencing cracking in tools that required weld repair or replacement of tooling before program completion, seriously jeopardizing program timing and component supply. Engineers and metallurgists at MetalTek’s Carondelet Division worked with the customer to review tooling designs for material selection and gating. The focus was to improve tooling machinability, increase performance, and reduce thermal cycle cracking. All parties agreed to the proper gating and design strategies, and MetalTek delivered custom-designed cast product within four weeks of order receipt, allowing the customer to meet program timing requirements.
2.) Centrifugal Casting Prevents Distortion and Keeps Forming Mandrels Round
Composite and sheet metal structures used in aircraft are hot formed around tooling that is typically a welded fabricated structure. Because of heat in the production process and the very large size of cases being produced, those tools are prone to deformation. This distortion results in tolerance and roundness issues in the finished part. The use of alloys such as Invar that resist thermal expansion, and the homogeneous nature of centrifugal castings used in this application eliminate roundness concerns and provide a high-quality finished part. MetalTek has provided castings to serve as tooling for several aircraft applications. Lab testing, as well as field performance, indicate that a centrifugal casting used for fan case tooling can provide five times the tool life of a traditional fabricated assembly.
3.) Sand Castings Used for Critical Fin Component in Aerospace Application
A prominent jet engine manufacturer lost its source for die block material to produce a critical fin component and needed to develop an alternative source as quickly as possible. With known short development time, MetalTek was approached due, in part, to our design and tooling capabilities. MetalTek uses ProE and AutoCAD for in-house design and employs Magma Soft for solidification simulation. That, combined with the ability to supply patterns in wood, synthetics, metals, and other materials, allowed MetalTek to respond quickly and efficiently to the customer’s compressed timing. Parts were poured using a cast super alloy, and the customer was able to make an orderly transition to a new vendor for this demanding application with confidence.