Which statement about using AM in investment casting is true?

Using additive manufacturing (AM) in investment casting introduces innovative techniques that enhance the traditional process. The correct statement asserts that powder bed fusion processes can create partially hollow patterns that may implode during dewaxing.

This phenomenon occurs because the AM methods, particularly those that use powder bed fusion, allow for complex internal geometries and varying wall thicknesses in the pattern. When these patterns are subjected to the dewaxing phase, where wax is melted away, any hollow spaces that are not appropriately vented may create a vacuum. This can lead to implosion as the external atmospheric pressure exceeds the internal pressure of the hollow cavities. Understanding this characteristic is crucial for optimizing design and ensuring successful casting outcomes.

The other choices lack accuracy in their claims about the capabilities and requirements of AM in investment casting. Specifically, AM can produce not only solid patterns but also intricate shapes that were previously difficult or impossible to manufacture using traditional methods. Investment casting certainly benefits from AM technology, as it allows for rapid prototyping and the production of complex features, reducing lead times and improving design flexibility. Lastly, AM processes do not universally require a solid master pattern; they can directly produce patterns from digital files, further demonstrating their versatility in casting applications.