PurposeTo provide a comprehensive state of the art review of environmental impact assessment (EIA) of existing rapid prototyping (RP) and rapid tooling (RT), and identify prospective research needs.Design/methodology/approachThe sparse literature on the EIA of RP and RT is balanced by that of the comparatively mature field of industrial ecology (IE). Hence, the review emphasizes portable IE measurement and evaluations methods. As RP and RT can also be viewed as design tools and mass customization manufacturing, other EIA may be needed.FindingsThe scarcity of research to date combined with rapid technological advances leaves a large number of unresolved issues. In addition, the special character of RP and RT, as design and manufacturing enablers implies that future research is needed.Research limitations/implicationsThis review is drawn from a technology in rapid evolution. Hence, unresolved issues focus on technologies that already are on the market and the research needs are formulated in terms of state of the art process research.Practical implicationsAs technological advances multiply, so does the number of unresolved environmental problems. The review of unresolved issues points to a pressing need to assess the consequences of RP and RT while identified research needs point the way to anticipated areas where further assessment methods will be needed.Originality/valueThis paper intends to raise awareness about the potential environmental impacts from RP and RT, by presenting the problems associated with current methods for measuring environmental effects and discussing some of the most urgent unresolved issues, specifically with respect to materials. Indirect effects of other uses of RP and RT are discussed only briefly for lack of available data.

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A novel technique for designing curves on surfaces is presented. The design specifications for this technique derive from other works on curvature continuous surface fairing. Briefly stated, the technique must provide a computationally efficient method for the design of surface curves that is applicable to a very general class of surface formulations. It must also provide means to define a smooth natural map relating two or more surface curves. The resulting technique is formulated as a geometric construction that maps a space curve onto a surface curve. It is designed to be coordinate independent and provides isoparametric maps for multiple surface curves. Generality of the formulation is attained by solving a tensorial differential equation formulated in terms of local differential properties of the surfaces. For an implicit surface, the differential equation is solved in three-space. For a parametric surface the tensorial differential equation is solved in the parametric space associated with the surface representation. This technique has been tested on a broad class of examples including polynomials, splines, transcendental parametric and implicit surface representations.

High‐pressure laser chemical vapor deposition (HP‐LCVD) is a powerful tool for growing complex microstructures at rapid rates. Not only is it possible to deposit functionally graded materials, but new metastable phases, alloys, and composite materials may be realized. In this paper, the diversity of microstructures that may be obtained through HP‐LCVD is demonstrated, including the growth of metastable materials, e.g., diamond‐like carbon (DLC). For the first time, a pressure–temperature (P–T) phase diagram has been created for HP‐LCVD, identifying nine distinct material phases of carbon from ethene. Regions of high sp3 content are identified via Raman spectroscopy. The kinetics, rate limitations, and thermodynamics of the process are also characterized at hyperbaric pressures, creating a first‐ever process‐rate map—covering the entire useful pressure range for ethene. Thermodynamically enhanced growth is also documented for the first time, where the contribution of the heat of reaction is much greater than the incident laser power—demonstrating a quasi‐self‐sustaining reaction. Finally, sufficient information is provided to reconstruct specific fiber geometries, structures, and growth rates for potential industrial production of carbon fibers from the gas phase.