Toxic metal reduction is at the forefront of many design considerations today; additive manufacturing has the ability to combine materials in ways other traditional processes cannot and has the potential to offer unique solutions to reduce hazardous materials needed in manufacturing. Tungsten carbide (WC) has been used as a substitute in wear applications where toxic processes are traditionally utilized, but it can be difficult to deposit high-quality, hard and durable coatings. Additionally, there is a need to apply WC coatings on surfaces not feasible with the current processes. Cold spray, a solid-state directed powder deposition process, is effective at depositing carbides, though powders must be thoughtfully designed to achieve desired mechanical properties. In this study, WC was investigated as a hard chrome alternative for wear applications. Various blend ratios and preparation methods were evaluated as feedstock powder and then sprayed. Feedstock characteristics were compared to cold spray performance. Cold spray consolidations were evaluated for coating porosity and hardness. It was found that when powder make-up and composition were optimized, a high-hardness and low-porosity material was made that will contribute to the reduction in dependency of Cr in wear-facing components.

Additive manufacturing is a rapidly expanding field, encompassing many methods to manufacture parts and coatings with a wide variety of feedstock. Metal powders are one such feedstock, with a range of compositions and morphologies. Understanding subtle changes in the feedstock is critical to ensure successful consolidation and quality control of both the feedstock and manufactured part. Current standards lack the ability to finely distinguish almost acceptable powders from barely acceptable ones. Here, novel means of powder feedstock characterization for quality control are demonstrated for the solid-state AM process of cold spray, though similar methods may be extrapolated to other additive methods as well. These characterization methods aim to capture the physics of the process, which in cold spray consists of high strain rate deformation of solid-state feedstock. To capture this, in this effort powder compaction was evaluated via rapidly applied loads, flowability of otherwise non-flowable powders was evaluated with the addition of vibration, and powder electrical resistivity was evaluated through compaction between two electrodes. Several powders, including aluminum alloys, chromium, and cermet composites, were evaluated in this effort, with each case study demonstrating the need for non-traditional characterization metrics as a means of quality control and classification of these materials.

Due to their high energy density, long lifespan and light weight, lithium ion (Li-ion) batteries accounted for $11.8 billion dollars in sales in 2012, that makes up 60% of total portable battery sales and 37% of total battery sales. The same factors also make them the best candidate for use in hybrid electric vehicles (HEVs) and electric vehicles (EVs). Currently in the US almost all spent lithium ion batteries are land filled, compared to other types of batteries, such as lead acid batteries, in which 97% are recycled. This presents a large amount of environmental waste. Based on current trends in Li-ion battery use, if Li-ion batteries are not recycled, global lithium reserves are expected to be depleted by 2050. Additionally, recycling Li-ion batteries presents an economic opportunity in through the recovery of key valuable metals, such as cobalt, nickel and copper. Currently, most Li-ion battery recyclers focus on recovering cobalt from LiCoO₂ cathode material or through the recovery of Co and Ni from the cathode materials via a high temperature pyrometallurgical approach. We propose a new methodology that uses a low temperature hydrometallurgical approach that has the advantage of having high efficiency of recovery. This process works regardless of the Li-ion batteries chemistry, shape and size and recovers Co, Ni, and Mn in the form of their hydroxides, which when sintered with recovered Li₂CO₃ produces new LiNixMn_yCo_zO₂ cathode materials. The regenerated cathode material, LiNi_xMn_yCo_zO₂ , has been tested and exhibits good electrochemical performance. In addition to the cathode material, copper, aluminium, steel, etc are also recycled. Figure 1