Interference Shielding Research Articles

Anisotropic mechanical and sensing properties of carbon black-polylactic acid nanocomposites produced by fused filament fabrication

3D-printable conductive polymers are gaining remarkable attention for diverse applications, including wearables, pressure sensors, interference shielding, flexible electronics, and damage identification. However, the relationship between the anisotropy of their mechanical and electrical properties remains rather unexplored. This study focuses on characterizing Polylactic Acid/Carbon Black nanocomposites manufactured through fused filament fabrication. It aims to investigate the effect of the orientation of 3D printing layers on the mechanical properties, failure mechanisms, and self-sensing capabilities of the 3D printed material. To this end, we use a coupled health monitoring system in which electrical resistance measurements are applied to diagnose the damage state of 3D-printed samples during tensile testing. The results provide novel insights into the strong dependence of the material behavior on 3D printing pattern orientation, suggesting avenues for optimizing mechanical and electrical anisotropy through a multi-objective approach. Additionally, they offer guidelines for designing self-sensing components for structural health monitoring applications and strain gauge sensors with superior performance.

“Heterodimensional Structure” Integrated Defect and Interface Engineering for Efficiently EMI Shielding and Electrochemical Response

AbstractTwo colossal global challenges remain energy scarcity and environmental pollution, having evolved into problems that human society cannot ignore. Therefore, developing a material with efficient electromagnetic (EM) interference shielding and electrocatalytic properties has become imperative in promoting sustainable development and establishing environmental protection systems. Herein, a heterodimensional structure is prepared by assembling 3D spirally grown VS2 with 2D FeCo‐LDH, which precisely manipulates macroscopic EM and electrochemical characteristics through defect and interface engineering. The results show that the heterodimensional structure presents an efficient shielding effectiveness of 30.2 dB at 18 GHz. Heterodimensional structure exhibits a low overpotential of 279 mV, achieving a current density of 10 mA cm−2 and a desirable stability. In addition, based on the unique electrochemical properties and EM response characteristics of the material, a special protective helmet is innovated. The helmet incorporating an autonomous oxygen supply, advanced pressure surveillance, and dynamic stealth supports a more exhaustive safeguard for missions amidst noxious gases, and situations necessitating clandestine operations. This research provides a new idea for the development of multifunctional EM active materials, showing great application prospects in the fields of aerospace engineering, energy, and EM security protection.

Synthesis and characterization of PANI-CZF nanocomposites for enhanced electromagnetic interference shielding

The Zn0.5Cu0.5Fe2O4 nano ferrites were prepared by the solution combustion method using aloe vera gel. The polyaniline-Zn0.5Cu0.5Fe2O4 nano ferrite composites were prepared by Ex-situ polymerization method with different weight percentage ratio. The prepared samples were examined by X-Ray diffraction, SEM, EDAX, BET, TEM, VSM and Impedance analyser to investigate their structural, morphological, elemental analysis, average pore size and the porosity, magnetic, and dielectric properties, respectively. The cubic spinel structure was confirmed by X-ray diffraction patterns. Addition of PANI to zinc-copper nano ferrite exhibits shift in crystalline peaks towards larger angle. The existence of spherical and clumped particles was revealed by SEM examination. The retentivity and coercivity are determined and the magnetic moment values were decreases with increase in PANI to the ferrite nanocomposites. The ac conductivity constant at lower frequency and there is a sudden increase and decrease in its value as a function of frequency shows resonance behaviour. The CZF-1 (CZF 30%) composite shows highest ac conductivity and dielectric constant. The electromagnetic shielding interference studies were conducted for S-band frequency. The CZF-1 (CZF 30%) nano composite shows highest shielding effectiveness as compared to other composite in the frequency range 2 to 3 GHz. The experimental result showed that these materials are used for applications in electromagnetic interference shielding.

Copper-nickel electroplating of 3D-printed acrylonitrile butadiene styrene for interference and radiation shielding applications

In this study, electromagnetic and radiation shielding structures were fabricated by 3D printing acrylonitrile butadiene styrene (ABS) structures via fused filament fabrication and electroplating with copper (Cu) and nickel (Ni) metals. Prior to electroplating, the printed ABS materials were made conductive by surface electrodepositon of polypyrrole (PPy). ABS adsorbs the pyrrole monomer, which subsequently polymerizes via oxidation forming conductive PPy layer on the printed structures. The successful anchoring of PPy layer can be attributed to its hydrogen bonding and electrostatic interactions with ABS. Thermal analysis, optical, and electron microscopy equipped with energy dispersive X-ray were employed to characterize the printed shielding structures, while the interference and radiation shielding effectiveness were evaluated using a spectrum analyzer and dosimeter, respectively. The interference shielding was found to be effective at 60 ± 5 dB over relatively small frequency range. Shielding was also apparent against gamma and X-ray ionizing rays, but more significantly effective against beta rays. Furthermore, the Cu/Ni coating was able to reduce any heat-induced dimensional changes for the 3D printed ABS substrate without compromising the mechanical integrity.

EMI shielding applications of PANI-Ferrite nanocomposite materials: A review

The issue of electromagnetic pollution, also known as electromagnetic interference (EMI), is brought on by the rapid development of electronic devices and wireless communication technology. The purpose of electromagnetic shielding interference is to shield the electronic device from interruptions and to prevent harm to the device. As a result, EMI shielding materials have been developed to address the pressing issue. In recent years, EMI shielding materials have changed from traditional single-function to multi-function designs to better accommodate diverse application contexts. Various strategies have been adopted to prevail over the limitations of metal-based EMI shielding materials. Ferrites and their composites have recently attracted the interest of researchers due to their biocompatibility, biodegradability, and variety of uses in various fields including EMI shielding. Ferrite nanocomposites are combined with Polyaniline (PANI) to form PANI-ferrite nanocomposites. In addition to having good qualities, polymer nanocomposites can be designed to display a combination of properties for multifunctional applications. When the particle size is decreased below 30 nm, the properties of ferrite particles, which are very relevant materials, perform better. Therefore, the size and distribution of the particles inside the polymer matrix play a major role in determining the superparamagnetic nature of ferrite particles and their polymer nanocomposites. In this work, we investigated ferrite-based materials for the reduction of EMI using reflection and absorption approaches. Also highlighted the popular techniques for the synthesis of ferrite composites and their EMI shielding efficiency.

Regulation binary electromagnetic filler networks in segregated poly(vinylidenefluoride) composite for absorption‐dominated electromagnetic interference shielding

AbstractExcellent conductivity and optimized impedance matching are vital for superior absorption‐dominated electromagnetic interference (EMI) shielding. An efficient binary electromagnetic filler network regulation method has been proposed. Poly‐ (vinylidenefluoride)‐ferroferric oxide‐reduced graphene oxide/single‐wall carbon nanotube (PVDF‐Fe3O4‐RGC) composite has been synthesized as a layered segregated polymer composite structure by using an electrostatic assembly and hot compression strategy. Binary electromagnetic filler networks have surpassed the obstacles of magnetic materials in conductive networks, and are thereby beneficial for outstanding conductivity and impedance matching. Therefore, a superior conductivity of 1.28 S cm−1 and an outstanding electromagnetic shielding interference and effectiveness of 44.5 dB have been obtained for loading of 2.02 vol.% single‐wall carbon nanotubes (SWCNTs), with an absorption rate larger than 85.0% in the X‐band. The enhanced EMI shielding performance is attributed to the regulation of the binary electromagnetic filler network.

Smart electromagnetic interference shields based on flexible PEDOT:PSS/Bi2Te3 films

Nowadays, the electromagnetic interference (EMI) shielding materials with an excellent electrical features, favorable flexibility and low density are the admirable desires that represent great challenges. Therefore, n-type bismuth telluride nanorods with diameter of 41.3 ± 5 nm (n-Bi2Te3) were incorporated into a p-type poly(3,4-ethylene-dioxythiophene):poly (styrenesulphonate) (p-PEDOT:PSS) to fabricate a (p-PEDOT:PSS/n-Bi2Te3) films for the electromagnetic interference shielding applications for the first time. Besides, the impact of n-Bi2Te3 nanorods on the electrical conductivity and the electromagnetic interference (EMI) shielding functions of p-PEDOT:PSS/n-Bi2Te3 films has been explored. The electrical conductivity (σ) has gradually increased with the n-Bi2Te3 nanorods in the shield films to obtain the highest value of 106.73 ± 6 S/cm at 16 wt%. Moreover, the total shielding effectiveness (SET) has also dramatically increased with the n-Bi2Te3 nanorods to obtain the highest value of 42.02 dB at 12 GHz for 16 wt%. The reflection mode is the dominance contribution in the shielding effectiveness process, presenting a good reflector of EM waves. Furthermore, the shield films have displayed a high mechanical performance with young modulus of 1.9 ± 0.3 GPa and tensile strength of 42.5 ± 5 MPa at 16 wt%. It can be suggested that these p-PEDOT:PSS/n-Bi2Te3 shields can be functionalized in many fields like electromagnetic shielding interference technology, military, electronic, smart fabric, wearable and biological apparatuses.

Micro-nanoarchitectonics of electroless Cu/Ni composite materials based on wood via heat treatment

This research aims to optimize the comprehensive performance of wood-based electromagnetic shielding interference (EMI) materials and master the effect of heat treatment on its coating density, interfacial morphology, conductivity, and hydrophobic and electromagnetic shielding. The results showed that the surface roughness of composite coatings was 11.0 μm when the wood was conducted via electroless two deposition Cu and one Ni and the heat treatment temperature was 150 °C. The composite coating’s surface gradually became more uniform with increasing temperature. The coating’s thickness via 120 °C heat treatment was 97.5 μm. Energy Dispersive Spectroscopy (EDS) spectra verified the existence of Cu and Ni particles. The heat treatment had an obvious influence on conductivity of composite materials and the pore network structure. The contact angle of composite materials reached 119°. The average electromagnetic shielding efficiency via 180 °C heat treatment was up to 91.4 dB in the frequency ranging from 300 to 3.0 GHz, which verified that the composite materials can shield 99.99% of the incident electromagnetic wave energy. The conductivity gradient structure can realize multi-dielectric interface loss and multiple reflection loss.

Effects of Y2O3 on the microstructure evolution and electromagnetic interference shielding mechanism of soft magnetic FeCoSiMoNiBCu alloys by laser cladding

Laser cladding is one of the new techniques for additive manufacturing of metal alloy-based electromagnetic shielding materials. However, it is generally difficult to prepare alloys with ideal printability, soft magnetism and electromagnetic interference (EMI) shielding effectiveness (SE) using this technique. To improve the electromagnetic shielding performance of laser cladded Fe-Co based soft magnetic alloys, a new FeCoSiMoNiBCu alloy was prepared by laser multilayer cladding using metal powders added with different content of Y 2 O 3 . The results show that the FeCoSiMoNiBCu alloys prepared under optimized laser processing parameters exhibit excellent soft magnetism and electromagnetic shielding properties. The microstructure of the prepared alloys is mainly composed of α (bcc) phase, Fe 2 B, YFe 10 Mo 2 and B 6 Co 21 Mo 2 phases. The Y 2 O 3 powder has played significant effects on the soft magnetism and electromagnetic shielding properties of the alloys. When added with 1.5 wt% Y 2 O 3 , the alloy samples exhibit the highest saturation magnetization (186.2 emu/g) together with a superior EMI shielding effectiveness of 95 dB at 23.5 GHz, which is a 25–58% improvement compared the alloy without adding Y 2 O 3 . The mechanisms for the improved EMI shielding performance of the laser cladded FeCoSiMoNiBCu alloys depend on a synergistic effect of enhanced dielectric loss and ohmic loss; specifically, the α-Fe mainly promotes the dielectric loss, while the ohmic loss is enhanced by a “fish-bone” shaped phase composed of α (bcc) phase, Fe 2 B, YFe 10 Mo 2 and B 6 Co 21 Mo 2 . This study provides a new theoretical and technical guidance for the development of high-performance EMI shielding alloys using laser cladding technique. • A new FeCoSiMoNiBCu alloy with excellent electromagnetic shielding effectiveness was successfully prepared by laser cladding. • The microstructure evolution mechanism of Y 2 O 3 promoted laser cladding FeCoSiMoNiBCu alloys was clarified. • The influence of the type, size and proportion of in-situ magnetic phases on the FeCoSiMoNiBCu alloy’s electromagnetic shielding interference model was established by the experiments and first-principles calculations. • The electromagnetic shielding interference effectiveness of the laser cladding new FeCoSiMoNiBCu alloy was improved about 25–58%.

Ultrathin flexible electrospun carbon nanofibers reinforced graphene microgasbags films with three-dimensional conductive network toward synergetic enhanced electromagnetic interference shielding

In recent years, graphene-based composite films have been greatly developed in the field of electromagnetic shielding interference (EMI). However, it is still a huge challenge to prepare graphene-based composite films with excellent mechanical properties, conductivity and electromagnetic shielding properties. In this work, we adopted a facile and effective method by annealing the alkali-treated polyacrylonitrile (aPAN) nanofibers reinforced graphene oxide (GO) composite films at 2000 °C to obtain graphene-carbon nanofibers composite films (GCFs). Microscopically, carbon nanofibers (CNFs) were intercalated into the graphene sheets, and microgasbags structure was formed during the heat treatment process. The special structure makes GCFs have superior tensile strength (10.4 MPa) at 5% strain. After repeated folding over 1000 times, the films still demonstrate excellent structural integrity and flexibility performance. Interestingly, the graphene-based composite films with 10 wt% aPAN nanofibers exhibit an extremely low density of about 0.678 g/cm3 and excellent electrical conductivity of 1.72 × 105 S/m. Further, an outstanding electromagnetic shielding effectiveness (SE) of 55–57 dB was achieved, and the corresponding value of the specific SE/thickness can reach 67,601–70,059 dB·cm2/g, which is the highest among reported graphene-based shielding materials. The significant electromagnetic shielding performance is due to the synergistic enhancement effect brought by the excellent conductivity of carbon nanofibers and graphene, the formed effective conductive network and the microgasbags structure. Electromagnetism simulation further clarified that the underlying mechanism should be mainly attributed to the conduction loss and multiple reflections caused by the special structure of GCFs. This work will provide new solutions for low density, high flexibility and excellent electromagnetic shielding properties materials in the next generation of foldable and wearable electronics.

Millefeuille-inspired highly conducting polymer nanocomposites based on controllable layer-by-layer assembly strategy for durable and stable electromagnetic interference shielding

High-performance conductive polymer nanocomposites containing two-dimensional (2D) MXene are garnering substantial interest for electromagnetic shielding interference (EMI) in flexible electronics. However, owing to the non-sticky nature and undesirable mechanical performances of freestanding MXene film, it remains a formidable challenge to make the trade-off between outstanding EMI shielding capability and high stability. In this study, inspired by the structure and manufacturing process of millefeuille cakes, we propose a controllably layer-by-layer assembling strategy for fabricating flexible multilayered EMI shielding composite films based on MXene and an inherently conductive polymer (ICP). The multilayer films bearing alternating aramid nanofibers/polypyrrole nanowires (AFPy) and Ti3C2Tx reinforced by waterborne polyurethane (Ti3C2Tx@WPU) layers are orderly constructed by a facile alternating vacuum filtration method. Benefiting from the special architectures, the AFPy-70/Ti3C2Tx@WPU-4 film exhibits a high electrical conductivity of 1.74 S cm−1 and superior EMI shielding effectiveness of 40.9 dB at lower Ti3C2Tx loading content (32 wt%). Moreover, synergistic integration of hydrogen bonding and π-π stacks in multilayered films is achieved, especially in tandem with controlled crack generation within the whole film. Excellent EMI shielding performance remains well maintained even after being suffered to back-and-forth bending test (over 10,000 cycles), ultrasonication, and cryogenic temperature, validating great potential as high-performance EMI shielding film resisting extreme conditions.

Thermal Spray Coatings for Electromagnetic Wave Absorption and Interference Shielding: A Review and Future Challenges

This review aims to consolidate scattered literature on thermally sprayed coatings with nonionizing electromagnetic (EM) wave absorption and shielding over specific wavelengths potentially useful in diverse applications (e.g., microwave to millimeter wave, solar selective, photocatalytic, interference shielding, thermal barrier‐heat/emissivity). Materials EM properties such as electric permittivity, magnetic permeability, electrical conductivity, and dielectric loss are critical due to which a material can respond to absorbed, reflected, transmitted, or may excite surface electromagnetic waves at frequencies typical of electromagnetic radiations. Thermal spraying is a standard industrial practice used for depositing coatings where the sprayed layer is formed by successive impact of fully or partially molten droplets/particles of a material exposed to high or moderate temperatures and velocities. However, as an emerging novel application of an existing thermal spray techniques, some special considerations are warranted for targeted development involving relevant characterization. Key potential research areas of development relating to material selection and coating fabrication strategies and their impact on existing practices in the field are identified. The study shows a research gap in the feedstock materials design and doping, and their complex selection covered by thermally sprayed coatings that can be critical to advancing applications exploiting their electromagnetic properties.

Injection Molding of Plastic Plates Combined with Boss Features on Superplastic Zn–22Al Sheet

Abstract This paper presents the development of a hybrid process combining forming of a superplastic zinc-aluminum sheet with injection molding. The product is a plastic part covered with a superplastic zinc-aluminum layer used mainly for electromagnetic interference (EMI) shielding. This paper investigates the moldability of Zn/Al sheet covered plates with various bosses. The effects on the moldability of various parameters, including: melt temperature, injection pressure, sheet thickness, various boss shapes and boss location in the mold, are investigated. It is found that bosses formed with thick Zn/Al sheet and located close to melt entrance exhibit good moldability. Among boss geometries, boss depth is the most critical parameter; a little increase in boss depth sharply lowers the mold-ability. Large angle improves moldability. To help interpret the effects of geometrical parameters, sheet deformation is observed by measuring the deformations in printed-grids and thickness. The base circle of the boss is found to be the most severely deformed region. The thickness reduction ratio in the center of base circle could help predicting moldability.

Isolated Solid Wall-Assisted Thermal Conductive Performance of Three-Dimensional Anisotropic MXene/Graphene Polymeric Composites.

The introduction of three-dimensional (3D) continuous conformations in polymer materials is a convincing proposal for acquiring the desirable multifunction to fulfill the urgent demands of highly integrated electronic devices. However, the limited functional design of the filled aligned network remains challenging. Herein, directional self-assembly 3D MXene/graphene aerogels are fabricated as conductive networks for polyethylene glycol (PEG) matrix. Based on the uniaxial and biaxial ice template method, the temperature gradient affects the aligned arrangement of the 3D microstructure. The biaxial PEG/MXene/GR composites exhibit an enhanced through-plane thermal conductivity of 1.64 W m-1 K-1 at 10.6 vol % content, which is 522% higher than that of pure PEG. The influence of the biaxial self-assembly strategy compared with that of the uniaxial one on the thermal conductivity reaches the highest 333% when the weight ratio equals 1:1. Meanwhile, the same difference also occurs in the electromagnetic shielding interference (EMI) property. The advanced EMI-shielding effectiveness of the biaxial PM1G1 composites reaches ∼36 dB at the 2.5 mm thickness. This research provides valuable guidance for designing high-performance applications of anisotropic thermal management and EMI shielding in 5G telecommunications and mobile electronic devices.

Design and development of a multi-functional bi-anisotropic metasurface with ultra-wide out of band transmission

This paper presents a multi-functional bi-anisotropic metasurface having ultra-wide out of band transmission characteristics. The proposed metasurface is comprised of 90° rotated T-shaped configuration yielding greater than or equal to 50% out-of-band transmission from above L- to X-band. Moreover, this metasurface achieves a maximum of 99% out-of-band transmission at lower frequency bands (i.e., L-band). The simultaneous absorptive and controlled reflection functionalities are achieved at 15.028 to 15.164 GHz along with polarization-insensitive and angular stable properties. The proposed metasurface yields state-of-the-art features compared to already published papers and has broader scope for Fabry Perot cavity, Radar cross-section (RCS) reduction, electromagnetic compatibility and interference (EMC/I) shielding, selective multi-frequency bolometers, ultrathin wave trapping filters, sensors and beam-splitters in the microwave domain.

Preparation of freestanding films from SWCNT/PANI nanocomposites using different blending techniques and characterization of their EMI shielding effectiveness in X-band

Synthetic polyvinyl alcohol (PVA) was used as a matrix, and polyaniline/SWCNT (PS) was used as a filler in the composite to create thin films for electromagnetic interference (EMI) shielding. The blending methods, namely mechanical stirring and ultrasonication, were used to produce composites (commercially available polyaniline (PANI) and single-walled carbon nanotube (SWCNT)). A solution casting process was used to create the composite films, which had a thickness of 0.5 mm. X-ray diffraction and field-emission scanning electron microscopy were used to examine the structural and morphological properties of the as-prepared composite films. Using a vector network analyzer, the effect of PANI/SWCNT composition on microwave shielding effectiveness (SE) of PVA was investigated and the efficiency of the EMI shield was evaluated. To select the effective films, the losses due to absorption, reflection, and total SE of the samples were measured. These findings show that absorption dominated total shielding effectiveness (SET) up to −18 dB in the 8.2–12.4 GHz (X-band) frequency range, implying their usefulness as microwave absorbers.

Efficient and cost-effective hybrid composite materials based on thermoplastic polymer and recycled graphite

Recycling of anode materials from lithium-ion batteries (LIBs) has been given less attention due to the abundance of graphite in the nature, the main material used in LIB anode layers, and its favorable cost. When concerns about environment and shortage of graphite resources become the main objective, then recycling of anode materials can play a significant role in this case. In this work, the graphite anode powder was recycled from LIBs in a very simple procedure including sequence steps of separation, dispersion and heat treatment. The reclaimed anode graphite powder was dispersed in ethanol then centrifuged five times, followed by a heat treatment process at 800 °C for 6 h under continuous nitrogen flow. Recycled graphite was directly used to synthesize hybrid composites by extrusion process. This type of graphite/polymer composites has the potential to be used as conductive polymer composites (CPCs). These composites have versatile functionalities that allow them to be used in several applications such as interference shielding and electrostatic dissipation. The structure, morphology, mechanical properties and electrical conductivity of the hybrid composites were analyzed by XRD, Raman spectroscopy, electron microscope, universal testing machine (UTM) and two probe method. Results showed that mechanical properties of the polymer were significantly improved with the increasing content of the recycled graphite. Morphology also indicated that the recycled graphite was homogeneously distributed in the polymer matrix compared to commercial graphite. Interesting results were observed in mechanical properties when the tensile strength and elongation percentage were compared between composites made from commercial graphite and recycled graphite. Recycled graphite based hybrid composite shows higher elongation and tensile strength compared to commercial graphite based hybrid composite. Conductivity of HDPE-recyl-GR-5% hybrid composite showed 3.81 × 10−8 S/cm, which is 10 orders of magnitude higher than that of HDPE polymer (1.17 × 10−18 S/cm) (insulator level, < 10–12 S/cm).

Adhesion strength enhancement of nickel-plated carbon fiber using edge selectively oxidized graphene

In this study, electroless nickel-plated carbon fiber (CF) was prepared with edge-selectively oxidized graphene (EOG) to reinforce the interface between nickel and CF for use in a composite for electromagnetic interference (EMI) shielding. The EOG layer was formed by generating ionic interaction through a modified layer-by-layer assembly between negatively charged EOG and positively charged polyethyleneimine (PEI). EOG-coated CFs with rough surfaces improved the specific surface area and adhesion strength with the nickel-plating layer. To evaluate the adhesion strength, the interfacial shear strength (IFSS) was investigated using microdroplet testing. After EOG coating, the interfacial bonding strength was enhanced by about 65%. The composite nickel-plated carbon fabric with EOG coating showed EMI shielding of around 58 dB, which is significant for future EMI shielding applications.

Study on Energy-saving Method of Microwave Monitoring for Detecting Human Physical Body and Shielding Interference from Regular Motion Objects

This paper explores a method of detecting human body by microwave that avoids the interference of regular motion. It can accurately detect the presence of human body in the presence of interference of regular moving objects, and is applied to the energy-saving control of power sockets to achieve energy-saving control. This method can also be used in water-saving control. This method solves problems related to resource waste in public buildings, especially problems in classrooms and offices in colleges and universities where there are ever-lasting lights air-conditioning and no people there other waste problems, which improves the level of scientific management, and saves a lot of energy. It can not only solve the problem of energy saving and control, but also realize the safety utilization of power of the device. According to the statistics, it can be guaranteed that there are more than 30% saving energy with low input. This method makes great contributions to environmental protection and social security. This method can be further promoted to be appiled to any control system which requires accurate human physical body detection and shielding interference from regular motion object, which will be progressively integrated into building clusters and municipal facilitie. It can also achieve data sharing, information interaction and centralized control of energy of the whole city.

A GPU Spatial Processing System for CHIME

We present an overview of the Graphics Processing Unit (GPU)-based spatial processing system created for the Canadian Hydrogen Intensity Mapping Experiment (CHIME). The design employs AMD S9300x2 GPUs and readily available commercial hardware in its processing nodes to provide a cost- and power-efficient processing substrate. These nodes are supported by a liquid-cooling system which allows continuous operation with modest power consumption and in all but the most adverse conditions. Capable of continuously correlating 2048 receiver-polarizations across 400[Formula: see text]MHz of bandwidth, the CHIME X-engine constitutes the most powerful radio correlator currently in existence. It receives 6.6[Formula: see text]Tb/s of channelized data from CHIME’s FPGA-based F-engine, and the primary correlation task requires [Formula: see text] complex multiply-and-accumulate operations per second. The same system also provides formed-beam data products to commensal FRB and Pulsar experiments; it constitutes a general spatial-processing system of unprecedented scale and capability, with correspondingly great challenges in computation, data transport, heat dissipation, and interference shielding.