Coefficient Of Thermal Expansion Matching Research Articles

Superconducting magnesium diboride films for levitation of laser targets

Inertial confinement fusion targets would benefit from being levitated inside hohlraums to avoid capsule support-related implosion perturbations. Levitation inside a magnetic trap requires coating the capsule with a thin film that is superconducting at 20 K. Such non-epitaxial film growth on non-planar substrates is challenging. Here, we study Mg vapor annealing and solid-phase reactive inter-diffusion methods to form superconducting magnesium diboride (MgB2) films on different planar and spherical carbon substrates, evaluating glassy carbon, polycrystalline diamond made by chemical vapor deposition, and carbon deposited by magnetron sputtering of graphite targets. Thin films of B and Mg are produced by magnetron sputtering onto stationary planar or rolling spherical substrates and annealed at either 600 or 850 ∘C in Mg vapor. The films are characterized by a combination of high-energy ion scattering, electron microscopy, and magnetometry. Results show that the critical superconducting temperature of resultant films depends on film microstructure and oxygen impurity content. The formation of MgB2 films is also strongly substrate dependent, even in this case of non-epitaxial growth. Important factors to consider are oxygen outgassing of the substrate during thermal processing, substrate surface roughness, and the matching of thermal expansion coefficients of different layers in the multilayer structure.

High-Temperature Thermal Conductivity and Thermal Cycling Behavior of Cu–B/Diamond Composites

Diamond particle-reinforced copper matrix (Cu/diamond) composites are currently considered as a promising thermal management material due to their high thermal conductivity and matching coefficient of thermal expansion (CTE) with the semiconductor. In this article, the Cu– <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$x\text{B}$ </tex-math></inline-formula> /diamond ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$x = 0.1$ </tex-math></inline-formula> –1.0 wt%) composites with 67% diamond volume fraction were produced by gas-pressure infiltration. The thermal conductivity of the Cu–B/diamond composites decreases with the increasing temperature from 323 to 673 K, owing to the property change of the composite components. The samples were subjected to 100 thermal cycles from 218 to 423 K to investigate the long-term stability of the Cu–B/diamond composites. The results suggest that the interface structure evolution plays a critical role in determining the high-temperature thermal conductivity and thermal cycling behavior of the Cu–B/diamond composites. By measuring the thermal properties before and after thermal cycling, we found that the Cu–0.5wt%B/diamond composite has the best thermal stability. After 100 thermal cycles, the room temperature thermal conductivity remains almost unchanged at ~740 W/mK, and the CTE increases slightly from 4.88 to 4.97 ppm/K. This article expands the understanding of the thermal properties of the Cu-B/diamond composites and provides a fundamental basis for their electronics packaging applications.

The Effect of Bond Phase Additive and Sintering Temperature on the Properties of Mullite Bonded Porous SiC Ceramics

Currently, porous SiC ceramics have been a focus of interesting research in the field of porous materials due to their excellent structural properties, high strength, high hardness, and superb mechanical and chemical stabilities even at high temperatures and hostile atmospheres. Porous SiC ceramics have been considered as suitable candidate materials for catalyst supports [1-2], hot gas or molten metal filters [3], high temperature membrane reactors [4], thermal insulating materials [5], gas sensors [6] etc. Porous SiC ceramics are fabricated by various methods including partial sintering [7], carbothermal reduction [8-9], replication or pyrolysis of polymeric sponge [10-12], reaction bonding [13] etc. In all these methods SiC needs to be sintered which requires a very high temperature due to the strong covalent nature of the Si-C bond, selective sintering additives, expensive atmosphere, costly and delicate instrumentation. Processing of porous SiC ceramics at low temperature using a simple technique thus becomes necessary. Bonding of SiC can be done at low temperatures by use of different oxide and non-oxide secondary phases. They include silica, mullite, cordierite, silicon nitride, etc. Various sintering additives are used for the formation of variety of secondary oxide bond phases for formations for porous SiC [14-19] Choice of mullite as a bond for SiC has many advantages. Mullite possesses a high melting point (Tm= 1850°C) and a low oxygen diffusion coefficient (5.6 x 10-14 m2/sec at 50°C). It has a matching thermal expansion coefficient with SiC (CTEmullite= 5.3 ×10-6/K; CTESiC = 4.7 ×10-6/K at RT-1000 °C) and a high strength that can be retained up to a very high temperature. Different sources of aluminum, such as Al2O3, Al, AlN, and Al (OH)3 powders were used for the formation of mullite bonded porous SiC ceramics (MBSC) [20-21]. However, the mullitization temperature of 1550o C is still necessary. In this work, mullite bonded porous SiC ceramics were fabricated by an in situ reaction-bonding process; the mixture of clay and CaCO3 were chosen as sintering additives to lower the mullitization reaction between Al2O3 and oxidation-derived SiO2. The effect amount of alumina, sintering temperature and other sintering aids on material property such as porosity/pore size distribution mechanical and micro structural properties of porous oxide bonded SiC ceramics were studied.

Modernist enamels: Composition, microstructure and stability

Coloured enamels from the materials used in Modernist workshops from Barcelona were produced and compared to those found in the buildings to explore the reason for the reduced stability of the blue and green enamels.They were made of a lead-zinc borosilicate glass with a low softening point, reasonable stability to corrosion and matching thermal expansion coefficient with the blown base glass, mixed with colourants and pigment particles. The historical enamels show a lead, boron and zinc depleted silica rich amorphous glass, with precipitated lead and calcium sulphates or carbonates, characteristic of extensive atmospheric corrosion. The blue and green enamels show a heterogeneous layered microstructure more prone to degradation which is augmented by a greater heating and thermal stress affectation produced by the enhanced Infrared absorbance of blue tetrahedral cobalt colour centres and copper ions dissolved in the glass and, in particular, of the cobalt spinel particles.

Synthesis of W-AG Nanoalloys and Computer Aided Thermal Analysis of W-AG Nanoalloys Based Heat Sink

W-Ag finds applications in many frontier areas such as heat sinks and microwave absorbers for microelectronics devices, arcing tips, resistance welding electrodes, electrical contacts and heavy duty electronic contacts. These nanoalloys prepared by mechanical milling process result in highly dense product. Chemical approaches have significant advantages in terms of better stoichiometric control, purity and controllable particle size. The variation in chemical composition of these composites allows the match of thermal expansion coefficient with ceramic substrates used in semiconductor devices. In the present study, Ag nanoalloys with average sizes below 200 nm were prepared using tungsten powder and silver nitrate as precursors. Compositional characterization of W-Ag nanoalloys was carried out using portable XRF.The developed material i.e. W-Ag is used as heat sink application in which the heat sink is modeled and thermally analyzed for evaluation of heat flux. The heat flux obtained was compared with aluminum heat sink. It was perceived that W-Ag heat sink exhibited superiority in withstanding higher temperature. Whereas, heat sink designed from aluminum was limited with their parameter which is thermal conductivity.

Stainless Steel as Substrate Material for High-Temperature Superconducting Tapes Processed Via the ISD MgO Route

Second-generation high-temperature superconducting (HTS) tapes strongly rely on the substrate material, in many cases Hastelloy C276 (“H-C276”). In order to ameliorate performance (and reduce the price) of superconducting tapes, replacement of H-C276 has been investigated. In this paper, the potential of the readily available austenitic stainless steels X2CrNiMo17-12-2 (“CrNiMo”) and X11CrNiMnN19-8-6 (“CrNiMnN”) as substrates is assessed. It was found that CrNiMnN is not suitable as a replacement for H-C276. Tensile stresses occurring at elevated temperatures during the HTS tape production result in plastic deformation of the CrNiMnN substrate. In the case of CrNiMo, however, plastic deformation was not observed after processing of the HTS tape. Electrical losses as a result of alternating currents beyond those of H-C276 did not occur due to the paramagnetic nature of CrNiMo. It is demonstrated that, for the very same processing parameters, HTS films deposited on electrochemically polished and buffered CrNiMo substrates exhibit similarly high critical current densities as on polished and buffered H-C276 substrates. The application of CrNiMo stainless steel reduces substrate costs considerably. More importantly, tapes processed on CrNiMo substrates withstand higher tension strains with respect to the reduction of the critical current compared to H-C276 substrates. This effect is interpreted to be a result of the matching coefficients of thermal expansion of the HTS layer and CrNiMo, resulting in lower residual tensile stress in the HTS layer after processing.

Property comparison of flexible Cu(InGa)Se2 thin film solar cells on Ti and Ni foils without diffusion barrier

Flexible Cu(InGa)Se2 (CIGS) solar cells on metallic substrates are highly desirable for versatile energy applications. However, related researches reported on CIGS devices usually used a diffusion barrier, which involves an issue of thermal expansion coefficient matching and complicates the fabrication process. In this study, CIGS solar cells were fabricated on Ni and Ti foils through selenization of metal stacks deposited by e-beam evaporation, without the use of diffusion barrier. The films on Ti foils showed (112) preferred orientation while those on Ni foils exhibited (220) preferred orientation, due to the different crystal orientation of substrates. In–Ni and Ga–Ni phase were observed in films prepared on Ni foils, which led to the existence of Cu2–xSe. As a result, the CIGS solar cells fabricated on Ni foils showed inferior photoelectric properties, whereas those on 50 and 100 μm Ti foils presented conversion efficiency of 4.9% and 6.6%. The discrepancy on efficiency between two cells on Ti foils was ascribed to the different structural properties induced by the thermal stress. After 100 bending cycles, efficiency of cells on 50 and 100 μm thick Ti foils decreased by 1.0% and 2.6% respectively, indicating that CIGS solar cell on 50 μm Ti foil is more promising as flexible device applied on harsh circumstance.

Microstructures and metal-ceramic bond properties of Co-Cr biomedical alloys fabricated by selective laser melting and casting

Selective laser melting (SLM) technique, based on a layer-by-layer production, was used to produce biomedical Co-Cr devices specifically developed for dental restoration applications. However, information on the metal-ceramic bond strength of SLM-manufactured parts was limited. In this study, SLM-fabricated Co-Cr alloy specimens were subjected to subsequent heat treatments (holding at 1150 °C for 1 h). The alloy microstructures were characterized by scanning electron microscopy (SEM) coupled with energy-dispersive x-ray spectroscopy (EDX), x-ray diffractometer (XRD), and transmission electron microscopy, whereas the bond properties were evaluated by 3-point bend tests and coefficient of thermal expansion (CTE) tests, as compared to casting (CAST) alloys. Results showed that SLM specimens exhibited fine grains and homogeneously dispersed intermetallic compounds, and the resultant XRD analysis revealed a predominated face-centered cubic γ-Co phase (72 %). Student's t-test demonstrated that bond strengths of SLM specimens (45.80 ± 1.91 MPa) were significantly lower than that of CAST specimens (54.05 ± 6.77 MPa) (P < 0.05), and SLM specimens with debonded surfaces analyzed via SEM/EDX analysis revealed a mixed fracture type of adhesive and cohesive fractures and lower area fractions of adherence porcelain. While porcelain firing, the microstructural evolution and thermal CTE matching seriously affected the metal-ceramic bond properties. SEM/EDX analysis of the metal-ceramic interface showed that reaction diffusion layers of CAST specimens were clearly thicker than that of SLM specimens, indicating that CAST specimens had a stronger chemical bonding force. Martensite transformation (γ →ε) occurred in the CAST metal matrix close to the interface, which was not found in the SLM specimens. Additionally, the dynamic thermal process revealed that CAST specimens exhibited superior CTE matching. Overall, Co-Cr alloy fabricated by SLM exhibited inferior metal-ceramic bond properties; however, it still meets the requirements for applications as dental prostheses (>25MPa specified in ISO9693).

Cobalt-Free Perovskite Oxide La0.6Sr0.4Fe0.8Ni0.2O3−δ as Active and Robust Oxygen Electrode for Reversible Solid Oxide Cells

Reversible solid oxide cells have received increasing attention due to high efficiency. Cobalt-free perovskite electrode has compatible thermal expansion coefficient matching with the electrolyte and the reversible operation to inhibit the segregation of Sr. Herein a novel cobalt-free La0.6Sr0.4Fe0.8Ni0.2O3−δ perovskite is developed and investigated as oxygen electrode for reversible solid oxide cells. The electrochemical performance of La0.6Sr0.4Fe0.8Ni0.2O3−δ oxygen electrode in fuel cell mode and electrolysis mode is investigated in detail. The maximum power density of 961 mW cm–2 and polarization resistance of 0.142 Ω cm2 at 800 °C can be achieved in fuel cell mode. While the cell is operated in electrolysis mode, the current density ranges from 0.53 A cm–2 at 750 °C to 1.09 A cm–2 at 850 °C with 50 vol % absolute humidity at 1.3 V, and the hydrogen generation rate can reach up to 1348.5 mL (cm2 h)−1 with 90 vol % absolute humidity at 800 °C. The reversible solid oxide cells show excellent reversibili...

Fabrication of double‐cladding Ho3+/Tm3+ co‐doped Bi2O3–GeO2–Ga2O3–BaF2 glass fiber and its performance in a 2.0‐μm laser

AbstractA novel double‐cladding Ho3+/Tm3+ co‐doped Bi2O3–GeO2–Ga2O3–BaF2 glass fiber, which can be applied to a 2.0‐μm infrared laser, was fabricated by a rod‐tube drawing method. The thermal properties of the glass were studied by differential scanning calorimetry. It showed good thermal stability and matching thermal expansion coefficient for fiber drawing when Tx−Tg &gt; 193°C and the maximum difference of the thermal expansion coefficient is 3.55 × 10−6/°C or less. The 2.0‐μm luminescence characteristics were studied using the central wavelength of 808 nm pump light excitation. The results show that when the concentration ratio of Ho3+/Tm3+ reaches 0.5 mol%:1.0 mol%, the maximum fluorescence intensity was obtained in the core glass, the emission cross section reached 10.09 × 10−21 cm2, and the maximum phonon energy was 751 cm−1. In this paper, a continuous laser output with a maximum power of 0.986 W and a wavelength of 2030 nm was obtained using an erbium‐doped fiber laser as a pump source in a 0.5 m long Ho3+/Tm3+ co‐doped glass fiber. In short, the results show that Ho3+/Tm3+ co‐doped 36Bi2O3–30GeO2–15Ga2O3–10BaF2–9Na2O glass fiber has excellent laser properties, and it is an ideal mid‐infrared fiber material for a 2.0‐μm fiber laser with excellent characteristics

Solar Energy Absorbing Materials that are Capable of Withstanding Long-Term Exposure at 600 °C: Research Strategy

Pipes for parabolic-trough solar energy collectors (PTSC) must be able to operate and withstand high temperatures in corrosive environments for a long time without changing its microstructure and losing its original properties. The stages of development of a new material and technology for solar energy collectors that allows the production of a PTSC solar energy-absorbing material that is capable of withstanding temperatures ≥ 600 °C for at least 250 days are described. This material is a glass-crystalline enamel coating that is adhered to tubular stainless steel pipes. Such enamel coatings have high coefficients of thermal expansion (CTE) that are similar to the metal surface. These matching CTEs allow the enamel coatings to resist flaking during the heating at 900 °C. The high-temperature resistance of the developed coating was ensured not only by specific additives added to the frit of the coating but also by an additional nanosized sol-gel coating over the enamelled metal substrate.

Enhanced Interfacial Adhesion and Thermal Stability in Bismuth Telluride/Nickel/Copper Multilayer Films with Low Electrical Contact Resistance

AbstractThe interfacial property between thermoelectric films and metal electrodes greatly affects the performance and practical application of thin‐film thermoelectric devices. Here, Ni intermediate layer is chosen and inserted into Bi2Te3/Cu to simultaneously regulate the electrical and mechanical performance of the interface. Meanwhile, Ar/H2 plasma cleaning is also adopted to optimize the interfacial connection during the sputtering process. Results show the interfacial element diffusion can be effectively blocked after the introduction of Ni interlayer, and the Bi2Te3/Ni/Cu multilayer thin film performs an excellent interfacial adhesion and maintains a low specific contact resistivity about 2.7 × 10−6 Ω cm2, which can be attributed to the matching of thermal expansion coefficient between Bi2Te3, Ni, and Cu, and the reduction of lattice mismatch. Furthermore, the Ni interlayer can also alleviate the degradation of interfacial mechanical and electrical properties after 1000 cycles of thermal shock, consequently enhancing the reliability and stability of the interfacial connection. This work provides an effective way to improve the comprehensive performance of multilayer interface in thin‐film thermoelectric devices.

Thermally Sprayed Large Tubular Solid Oxide Fuel Cells and Its Stack: Geometry Optimization, Preparation, and Performance

In this study, we develop a large tubular solid oxide fuel cells design with several cells in series on a porous cermet support, which has many characteristics such as self-sealing, low Ohmic loss, high strength, and good thermal expansion coefficient matching. Here, we investigate aspects of the cell design, manufacture, performance, and application. Firstly, the cell length and number of cells in series are optimized by theoretical analysis. Then, thermal spraying is applied as a cost-effective method to prepare all the cell components. Finally, the performance of different types of cells and two types of stacks is characterized. The maximum output power of one tube, which had 20 cells in series, reaches 31 and 40.5 W at 800 and 900 °C, respectively. Moreover, the output power of a stack assembled with 56 tubes, each with ten cells in series, reaches 800 W at 830 °C. The excellent single tube and cell stack performance suggest that thermally sprayed tubular SOFCs have significant potential for commercialized application.

Glass-Free CuMoO4 Ceramic with Excellent Dielectric and Thermal Properties for Ultralow Temperature Cofired Ceramic Applications

A new glass-free low temperature sinterable CuMoO4 ceramic was prepared by a solid state ceramic route. The structural, microstructural, electron dispersive spectrum, and X-ray photoelectron spectroscopy analysis revealed the quality of the material synthesized. The CuMoO4 ceramic sintered at 650 °C exhibits densification of 96% and low coefficient of thermal expansion (CTE) of 4.6 ppm/°C in the temperature range of 25–500 °C. It has relative permittivity (er) of 7.9, quality factor (Qf) of 53 000 GHz, and temperature coefficient of resonant frequency (τf) of −36 ppm/°C (25–85 °C) at 12.7 GHz. The sintered ceramic also shows er of 11 and low dielectric loss (tan δ) of 2.7 × 10–4 at the frequency of 1 MHz. The full width half-maximum (fwhm) of A1g Raman mode of CuMoO4 ceramic at different sintering temperatures correlate well with the Qf values. The low sintering temperature, low relative permittivity, high-quality factor, and matching coefficient of thermal expansion to that of Si make CuMoO4 a suitable c...

High emissivity MoSi2–TaSi2–borosilicate glass porous coating for fibrous ZrO2 ceramic by a rapid sintering method

A MoSi2-TaSi2-borosilicate glass porous coating was designed and prepared on fibrous ZrO2 ceramic with slurry dipping and subsequent rapid sintering method. The microstructure, radiative property and thermal shock behavior of the coating have been investigated. The results show the coating presents a top Ta-Si-O compound glass layer and a porous MoSi2-TaSi2-borosilicate glass inner layer. The total emissivity of the coating is up to 0.88 in the range of 0.3–2.5 μm and 0.87 in the range of 2.5–15 μm at room temperature. The increased surface roughness leads to the increased emissivity, which can be explained by “V-shaped grooves” model. The coating turns into a dense structure and presents an interlocking structure in the interfacial layer after thermal cycling between 1673 K and room temperature 10 times, exhibiting excellent thermal shock resistance, which was attributed to the synergistic effect of porous structure and the match of thermal expansion coefficient between the coating and substrate.

Characterization of latticed SiC nanowires containing coating for carbon foam using carbonization activated pack cementation process

In order to improve the oxidation resistance of carbon foam, a silicon carbide (SiC) coating was prepared using carbonization-activated pack cementation method. Carbon foam was firstly carbonized partially at 500 °C and then fully carbonized at 1600 °C with pack powder containing activated carbon, silicon powder, and iron chloride. The as-obtained coating was characterized using scanning and transmission electron microscopies, X-ray diffraction, thermogravimetric analysis, oxidation thermal shock and coefficient of thermal expansion. The results showed that the coating was mainly composed of randomly distributed SiC nanowires extended inside the surface pores forming pinning effect. The growth mechanism involved dissolution of SiO and CO (vapors) in the Fi-Si melt (liquid) and precipitation of one-dimensional SiC nanowires (solid). In non-isothermal oxidation, the coated carbon foam showed a mass loss of only 1.97%. The thermal shock results indicated that due to matching of thermal expansion coefficients, no cracks occurred on the surface after 15 cycles under temperature drop of 1475 °C. Consequently, we expect that this new high temperature coating method, and the subsequent microstructure that it creates, can be widely applied to improve the thermal shock and oxidation resistance of carbon foam.

Design of a Low Inductance Power Module Based on Low Temperature Co-fired Ceramic

Abstract Efficient, compact, and reliable power electronic modules are building blocks of modern day power electronic systems. In recent times, wide bandgap semiconductor devices, such as, silicon carbide (SiC) and gallium nitride (GaN), are widely investigated and used in the power electronic modules to realize power dense, highly efficient, and fast switching modules for various applications. For high power applications is it required to parallel and series several devices to achieve high current and high voltage specifications, which results in larger current conducting traces. One of the major obstacles in using these wideband gap power semiconductor devices are the internal module stray inductance that is associated with these current conducting traces. With increasing demand for higher switching frequency, the internal module parasitic inductance must be reduced to as minimum as possible in order to utilize the full potential of the wide bandgap devices. A multi-layer approach of low-temperature co-fired ceramic (LTCC) to package the wide bandgap devices is investigated. The multi-layer design freedom by using LTCC can be utilized to reduce the footprint of the overall power module, electrical interconnects, hence, reducing the package parasitic inductance. LTCC also facilitates high temperature operations and has a coefficient of thermal expansion matching with wide bandgap devices. In this paper, we report on a LTCC based power module design where LTCC is utilized as an isolation layer between the source and the drain of the power devices. A simulation based parasitic inductance analysis and electro-thermal-mechanical study is performed using ANSYS Workbench Tools to investigate the feasibility of this LTCC based design.

High emissivity MoSi2–ZrO2–borosilicate glass multiphase coating with SiB6 addition for fibrous ZrO2 ceramic

To develop a high emissivity coating on the low thermal conductivity ZrO2 ceramic insulation for reusable thermal protective system, the MoSi2–ZrO2–borosilicate glass multiphase coatings with SiB6 addition were designed and prepared with slurry dipping and subsequent sintering method. The influence of SiB6 content on the microstructure, radiative property and thermal shock behavior of the coatings has been investigated. The coating prepared with SiB6 included the top dense glass layer, the surface porous coating layer and the interfacial transition layer, forming a gradient structure and exhibiting superior compatibility and adherence with the substrate. The emissivity of the coating with 3wt% SiB6 addition was up to 0.8 in the range of 0.3–2.5μm and 0.85 in the range of 0.8–2.5μm at room temperature, and the “V-shaped grooves” surface roughness morphology had a positive effect on the emissivity. The MZB-3S coating showed excellent thermal shock resistance with only 1.81% weight loss after 10 thermal cycles between 1773K and room temperature, which was attributed to the synergistic effect of porous gradient structure, self-sealing property of oxidized SiB6 and the match of thermal expansion coefficient between the coating and substrate. Thus, the high emissivity MoSi2–ZrO2–borosilicate glass coating with high temperature resistance presented a promising potential for application in thermal insulation materials.

Composite electroplating to enhance the GMI output stability of melt-extracted wires

Impedance output stability of Co-rich amorphous wires depends largely on the wire-terminal-connection, which can be accomplished by composite electroplating towards a robust sensor application. The present experimental results indicated that Ni/Cu composite layer composed of Ni, Cu plating and passivating treatment show a homogeneous microstructure, and excellent surface wettability, weldability and thermal expansion coefficient matching under variable temperature of wire-terminal-connecting. The properties of composite electroplated layer are mainly influenced by cathode current density, electroplating time and electrolyte temperature. The inhomogeneous distributed clustering-regions, disproportionated reaction, tendency of hydrogen brittleness and crack have been reduced by optimized coactions of intermolecular Van der Waals force, inner diffusion and mechanical bonding of electroplated layer. Therefore, the wire-terminal-connection is able to effectively improve impedance output stability by minimizing the disturbance of stray capacity, decreasing radio-frequency wave emission and electromagnetic signal attenuation, and suppressing the destabilization or concussion.

How Can Millions of Aligned Graphene Layers Cool High Power Microelectronics?

Thermal management is an increasingly critical problem in today's microelectronics industry. As power requirements increase and size requirements decrease, innovative materials with high thermal conductivity (TC), light weight, and many times low coefficient of thermal expansion (CTE) are desired to solve these thermal challenges. Thermal Pyrolytic Graphite (TPG*), a unique synthetic material produced by Momentive via chemical vapor deposition, contains millions of layers with highly-oriented stacked graphene planes and exhibits excellent in-plane thermal conductivity (&amp;gt;1500 W/m-K) and very low density (2.25g/cm3). In order to take advantage of its superior properties for thermal management, various forms of TPG-metal composite products were developed in the past few years. TPG composite with metal encapsulation simultaneously achieves high thermal conductivity from the TPG core and high mechanical strength from the metal shell. Momentive's proprietary bonding technology enables an intimate and strong joint between TPG and dissimilar metals, including Al, Cu, Sn, WCu, MoCu, AlSiC, and AlBe. In addition, the variety of compatible metals adds new functionalities to the TPG composite, such as platability and solderability for direct die attachment, CTE matching to semiconductor, and flexibility for off-plane connectivity. Also in this paper, three TPG composite categories, i.e.: TC1050* Heat Spreader, TPG Heat Sink and TPG Laminate, will be discussed in detail. Individually, their design guidance, performance, reliability, and application examples will be shared with the reader. With these three TPG composite products, Momentive has translated our extensive experience and success in thermal management at the system level, with TC1050 Heat Spreaders, to the device level, with TPG Heat Sinks and TPG Laminates.