I've been working on a few product ideas that would be 3D printed from titanium or stainless steel, and the methods by which 3D printed parts are specified has been on my mind throughout the process. The following passage, taken from the IDA Science and Technology Policy Institute's 2012 report "Additive Manufacturing: Status and Opportunities" sums up my feelings quite nicely. Note: "AM" refers to "additive manufacturing, which is a slight superset to the processes casually described as "3D printing." Emphasis is mine.
AM technology has made significant strides over the past 25 years, but technical challenges related to materials, equipment, and applications remain. Many of the challenges described in this section, which have commonly been discussed in workshops or publications, are the focus of ongoing research in government agencies or industrial organizations. In some cases, the topics may be underfunded by the private sector and could benefit from new or additional Small Business Innovative Research funding.
Information is needed on material properties for different processes, but who would maintain such a database and which data should be publicly available are unclear. Before the AM industry can fully transition to offering viable manufacturing solutions, specifications are needed that provide mechanical properties data for available materials, as well as more detail on how parts made from these materials perform (Campbell et al. 2011). Engineers and designers cannot design without fully understanding the properties of the materials used to manufacture the parts being designed. If the properties for AM materials are not available, designers will not consider additive manufacturing as a method of manufacturing. With so many AM processes and materials currently available, the creation of comprehensive specifications is a resource-intensive endeavor, requiring the involvement of research organizations and system and material manufacturers (Kinsella 2011).
Worth noting: despite knowing the difference between yield strength and ultimate tensile strength, I am not an engineer. But having access to full material data - as well as data on how parts made of that material perform - would be incredibly useful, even to a dullard like me.