38results about How to "Reduce thermal mismatch" patented technology

Embodiments for minimizing relative thermal growth within a fuel nozzle of a gas turbine combustor are disclosed. Fuel nozzle configurations are provided in which a heating fluid is provided to one or more passages in a fuel nozzle from feed holes in the fuel nozzle base. The heating fluid passes through the fuel nozzle, thereby raising the operating temperature of portions of the fuel nozzle to reduce differences in thermal gradients within the fuel nozzle. Various fuel nozzle configurations and passageway geometries are also disclosed.

The present disclosure discloses a method for transferring micro-light emitting diodes, a micro-light emitting diode device and an electronic device. The method for transferring micro-light emitting diodes comprises: providing bumps of bonding agent on electrode bonding pads of a receiving substrate and / or on micro-light emitting diodes of an original substrate; aligning and contacting the electrode bonding pads of the receiving substrate and the micro-light emitting diodes of the original substrate, to position the bumps of bonding agent between the micro-light emitting diodes and the electrode bonding pads; irradiating locally by using a first laser from the original substrate side, to melt the bumps of bonding agent to bond the micro-light emitting diodes and the electrode bonding pads;and stripping off the micro-light emitting diodes from the original substrate, to transfer the micro-light emitting diodes to the receiving substrate. The present disclosure, by heating quickly and locally by laser irradiation, avoids the overall warming-up of the receiving substrate and the original substrate, reduces the heat mismatch phenomenon, optimizes the flow of the bonding of the micro-light emitting diodes, and facilitates the controlling.

The invention discloses a Sm-Gd-Dy tri-rare-earth ion tantalate and a preparation method and application thereof. The general chemical formula of the Sm-Gd-Dy tri-rare-earth ion tantalate is SmGdDy<c>TaO<7>, wherein the a, b and c meet the relationship of a+b+c=3 and are separately in a range of 0.8-1.2. The preparation method comprises the following steps: (1) weighing samarium nitrate, gadolinium nitrate, dysprosium nitrate and tantalum oxalate according to a stoichiometric ratio, performing mechanical mixing with citric acid with a preset amount under a heat preservation condition, adding a concentrated ammonia water neutralization solution during the mixing process, and carrying out mechanical mixing to promote a complexation reaction under a heat preservation condition; and (2)drying the obtained solution, and then carrying out calcination at a high temperature to remove carbon impurities to obtain the Sm-Gd-Dy tri-rare-earth ion tantalate powder. The Sm-Gd-Dy tri-rare-earth ion tantalate has good high-temperature thermal stability and low thermal conductivity, and can be used as a thermal barrier coating material.

The invention discloses a low-temperature epitaxy preparation method of a germanium-silicon film with high germanium content. The low-temperature epitaxy preparation method comprises the following specific steps: (1) providing a silicon substrate with a (100) crystal face; (2) carrying out deoxidation on the silicon substrate at the temperature of 1350 DEG C, wherein the deoxidation lasts for 10 minutes; (3) through a molecular beam epitaxy method, growing a silicon buffer layer with the thickness of 20 to 50 nm on the silicon substrate after deoxidation, wherein the growth temperature is 700 DEG C; and (4) cooling the silicon buffer layer to a growth temperature which is below 300 DEG C, then growing GexSi1-x alloy, and adjusting the content of Ge, namely an x value, by changing the growth rates of Ge and Si. According to the preparation method, the high-quality germanium-silicon (GexSi1-x) film material with adjustable lattice constants can be directly grown on the silicon wafer at low temperature, and the content of germanium at most can reach 83%. The method does not need to adopt a layer-by-layer growth pattern for improving the content of germanium layer by layer, so that the method is simpler in operation and lower in cost.

The invention discloses a low-temperature glass solder bonding and packaging method based on wafer-level glass microcavities, which comprises the following steps: firstly, utilizing a silk-screen printing process to coat low-temperature glass solder on a packaging contact part of a Pyrex7740 glass substrate provided with a microcavity structure, preliminarily drying the low-temperature glass solder, and making the low-temperature glass solder be cured and cling to the Pyrex7740 glass substrate provided with the microcavity structure; secondly, aligning a Pyrex7740 glass packaging wafer which is cured with the low-temperature glass solder and a silicon substrate wafer comprising an MEMS device or a CMOS circuit, and making the microcavity structure on the Pyrex7740 glass substrate correspond to the position of the MEMS device or the CMOS circuit to be packaged of a silicon substrate; and thirdly, using a clamper to firmly clamp the two aligned wafers, applying the pressure, sintering the glass solder in a specified packaging atmosphere, and cooling the glass solder. The whole process is based on integral processing of the silicon wafer and the Pyrex7740 glass wafer, belongs to a process for manufacturing and packaging a wafer-level MEMS, and has the characteristics of simple method, adjustable packaging space and low cost.

The invention discloses anti-oxidation ZrB on the surface of C-C composite material 2 ‑SiC‑Y 2 O 3 ‑SiC coating and method of making the same. First, a SiC transition layer was prepared on the surface of the C-C composite matrix by embedding and infiltration technology, and ZrB was prepared on the SiC transition layer by embedding and infiltration. 2 ‑SiC‑Y 2 O 3 outer coating. in ZrB 2 ‑SiC‑Y 2 O 3 The introduction of a SiC transition layer between the coating and the substrate can alleviate the mismatch of thermal expansion coefficients, release thermal stress, and further improve the oxidation resistance of the coating. The present invention adopts two-step embedding and infiltration technology to prepare ZrB 2 ‑SiC‑Y 2 O 3 ‑SiC composite coating has little thermal damage to the C‑C substrate, strong bonding force of the coating, and dense coating. The SiC transition layer effectively relieves the mismatch between the thermal expansion coefficients of the outer coating and the substrate, reduces the cracking of the outer coating due to thermal stress, improves the bonding force of the coating, and effectively improves the oxidation resistance of the coating.

The invention relates to a low-heat-dissipation motorcycle engine manufacturing method. The manufacturing method includes the following steps that a piston, an air cylinder cover and an air cylinder body of an engine are subject to ultrasonic cleaning, and a spraying zone is subject to sand blasting through No.40 corundum gravels after washing is finished; a low temperature high velocity flame spraying is adopted for spraying the top surface of the piston and the inner surface of the air cylinder cover to form NiCoCrAlYTa bonding layers, and atmospheric plasma spraying is adopted for spraying the outer surface of the air cylinder body to form a NiCrAl bonding layer; and after the bonding layers are formed through spraying, the top surface of the piston, the inner surface of the air cylinder cover and the outer surface of the air cylinder body are subject to 7YSZ ceramic layer atmosphere plasma spraying. By means of the manufacturing method, through compounding of a ceramic material and a metal material, advantages of the two kinds of materials can be integrated, the defect that in the prior art, a view is given to manufacture pure ceramic engine parts is overcome, and therefore a motorcycle engine which is low in cost, high in heat isolation, resistant to oxidation, resistant to corrosion and long in service life is obtained.