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Cemented tungsten carbide (WC) is commonly used for wear-resistant applications, such as cutting tools and abrasives due to its extremely high hardness. This hardness leads to post-process machining of WC to be time-and cost-intensive. This study examined the feasibility of additive manufacturing of cemented WC to near-net-shape in an effort to reduce post-process machining. The binder phase in the manufactured samples is an iron-based alloy, which has a lower melting temperature than cobalt, the conventional binder in cemented WC. In this proof-of-concept study, cuboid specimens of WC with a low content of the iron-based alloy binder were printed; the effect of different processing conditions on the resultant density and microstructure of the material were investigated. Theoretical densities as high as 95% were achieved using this method. Artifacts indicative of the manufacturing process are present in the samples, and the challenges in removing the processing history from the final microstructure are discussed.

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Glass plays an important role in many engineering applications including transparent armor. Determining the actual strength of a glass is problematic because typical glass strength numbers are presented in the literature as ranges. Minor changes in surface finish, composition, test method employed, and processing all influence the mechanical strength of glass. A standardized method needs to be utilized to ensure that strength data can be compared universally. The use of a standard methodology is vital when comparing glass compositions or multiple sample lots of the same composition in order to attribute any real strength variations to the glass itself. While the procedures established in ASTM C1499 provide a good framework for glass strength measurement, flexibility in the experimental parameters of the standard allow for substantial strength variations when testing glass materials. The ratio between the load and support ring diameters, as well as the specimen dimensions, is shown to lead to variations in both the measured strength, as well as the number of valid/invalid tests based on where fracture initiates. The goal of this study is to quantify these effects in order to establish optimized testing conditions for determining the strength of float glass.

Additive manufacturing is transforming electronics, attributed to the rapid‐prototyping of complex electronic geometries. Herein, aerosol jet printing of nanostructured copper on ceramics is reported, enabling high‐temperature hybridized conductors with the ampacity of 2.05 × 109 A m−2 and a negative temperature coefficient of −0.07% °C−1 when subjected to extreme thermal shock. The atomized material jetting results in a layer‐by‐layer transfer of copper nanoplates, which incorporate a graphene precursor, dopamine, to ensure uniform deposition of conductive materials. Incorporation of graphene in copper maintains the intrinsic electric conductivity of copper while enhancing its ampacity and thermal conductivity, as well as exhibiting a negative temperature coefficient. The mechanistic studies suggest that the graphene formed suppresses the grain growth of the crystallites of hybridized copper–graphene conductor at high temperature. This hybridized conductor through aerosol jet printing is capable of withstanding elevated temperatures and can be utilized for the electronics for harsh environments.