Ceramic Layer Composites in Advanced Automotive Engineering and Biomedical Applications

2007 ◽  
Vol 333 ◽  
pp. 177-194
Author(s):  
Rainer Gadow
Keyword(s):  
Biomedical Applications ◽  
High Performance ◽  
Cylinder Liner ◽  
Flame Spraying ◽  
Robot Kinematics ◽  
Light Weight ◽  
Operational Load ◽  
Macro Scale ◽  
Novel Material ◽  
High Flexibility

Light weight engineering and composite technologies are key strategies in modern product development in mechanical engineering as well as in biomedical applications, where innovation is driven by novel material concepts and surface functionalities. Designed or customized surface properties by advanced coating technologies are an important discipline in this context. Ceramic, metallurgical and cermet layers can be manufactured in a most appropriate way by high energetic thermokinetic deposition techniques like plasma spraying, electric arc and last not least by supersonic flame spraying (HVOF). These technologies perform high deposition rates, high flexibility to use various materials and their combinations and applications in micro to macro scale products. The final properties of the coatings and layer composites do not just depend on the properties of the combined materials but, as in the case of ceramic coated light metals, are distinctly affected by the occurring residual stresses and their interaction with operational load stresses. With respect to the complex geometries of most components, their dimensional and positional tolerances a further strong influence of the robot kinematics of the plasma or HVOF torches during coating manufacturing is observed. By combining the expertise in materials and manufacturing engineering coatings and composites with high performance and reliability can be achieved. This is shown in the development of functionally coated cylinder liners and crankcases for ultra light weight engines as well as for ceramic coated bioinert and biodegradable substrates in medical surgery. It will be shown that cast engine block bores can be directly coated by using an automated HVOF process, obtaining improved coating results. The internal coating process by hypersonic flame spraying is a superior technological alternative to the APS process for high quality cylinder liner and engine crankcase applications. The applications of such ceramic and cermet coatings are not limited to automotive and biomedical applications, i. e. for wear and friction properties or biomedical compatibility, but can be used for tailored thermophysical, electrophysical or catalytic properties in various technical systems.

Application of Supersonic Flame Spraying for Next Generation Cylinder Liner Coatings

2012 ◽  
Vol 533 ◽  
pp. 91-97 ◽  
Author(s):  
Andrei Manzat ◽  
A. Killinger ◽  
R. Gadow
Keyword(s):  
Corrosion Resistance ◽  
Surface Topography ◽  
High Performance ◽  
Combustion Engine ◽  
Cylinder Liner ◽  
Flame Spraying ◽  
Oil Consumption ◽  
Functional Coatings ◽  
Coating Materials ◽  
Cylinder Liners

Rising demands for ecologically friendly automotive engines require a significant decrease in fuel consumption and emissions. Also the recent trend of downsizing engines demands for high performance materials for internal combustion engine applications. Tribologically functional coatings applied by supersonic flame spraying help in boosting the engine efficiency by reducing the internal friction and improving the durability and wear resistance of the cylinder running surface much-needed for engine downsizing tasks together with a high corrosion resistance enabling the use of bio fuels. In addition, the tailored surface topography of the thermal spray coatings help in supporting advantageous friction states and thereby show the benefit of reducing the oil consumption resulting in reduced emissions. The thermally sprayed coatings were applied using HVOF and HVSFS processes together with a specially designed spray gun trajectory in order to achieve a fast and cost efficient coating procedure. Several different coating materials, including novel nanostructured powders, have been investigated and compared to state-of-the-art cylinder liners. The performance of the coated cylinder liners regarding wear and corrosion resistance, friction coefficient and effects of the surface topography have been investigated in various test setups including engine tests.

Ceramic and Cermet Coatings for Cylinder Liner in Ultra Light Weight Engines - Novel Processing and Manufacturing of Ceramic Layer Composites

2006 ◽  
Vol 45 ◽  
pp. 1330-1335 ◽  
Author(s):  
Rainer Gadow ◽  
D. López ◽  
A. Candel
Keyword(s):  
Cylinder Liner ◽  
Cost Effective ◽  
Light Metal ◽  
Engine Block ◽  
Flame Spraying ◽  
Light Weight ◽  
Operation Conditions ◽  
Novel Processing ◽  
Sprayed Coating ◽  
The Cost

Actual requirements in the automotive industry are the reduction of fuel consumption and pollution emission, engine efficiency improvement, as well as cost reduction. Most of these requirements are fulfilled by reducing the total weight of the vehicle. This results in an increasing utilization of light metal components for engine applications. Significant weight savings are obtained by changing the engine block material from cast iron to aluminum or even to magnesium aluminum hybrid constructions. Despite of all advantages the industrial implementation of light metals is often inhibited by their poor surface properties especially concerning wear and tribological behavior. Due to the highly loaded operation conditions a cylinder liner surface reinforcement is necessary. A very promising technological alternative is the internal cylinder reinforcement by using HVOF (high velocity oxygen fuel) sprayed coatings. By using these advanced high energetic coating technologies, material combinations containing solid lubricant ceramic dispersions can be deposited. The thermal spray processes represent a cost effective and flexible solution for ultra light weight engine technology. This research is focused on the development of HVOF sprayed coating systems for cylinder liners, the coating optimization and the cost effective implementation of this hypersonic spray technology in a series production process. It will be shown that cast engine block bores can be directly coated by using an automated HVOF process, obtaining improved coating results. The internal coating process by hypersonic flame spraying is a superior technological alternative to the APS process for high quality cylinder liner and engine crankcase applications.

Fused Ambipolar Aza-isoindigos with NIR absorption

2021 ◽  
Author(s):  
Liping Yao ◽  
Danlei Zhu ◽  
Hailiang Liao ◽  
Sheik Haseena ◽  
Mahesh kumar Ravva ◽  
...  
Keyword(s):  
Organic Semiconductors ◽  
High Performance ◽  
Low Cost ◽  
Light Weight ◽  
The Past ◽  
Pi Conjugated ◽  
Nir Absorption ◽  
Conjugated Organic Semiconductors

Due to their advantages of low-cost, light-weight, and mechanical flexibility, much attention has been focused on pi-conjugated organic semiconductors. In the past decade, although many materials with high performance has...

scholarly journals Solution-Processed Transparent Conducting Electrodes for Flexible Organic Solar Cells with 16.61% Efficiency

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Juanyong Wan ◽  
Yonggao Xia ◽  
Junfeng Fang ◽  
Zhiguo Zhang ◽  
Bingang Xu ◽  
...  
Keyword(s):  
Solar Cells ◽  
Work Function ◽  
Organic Solar Cells ◽  
High Performance ◽  
High Efficiency ◽  
Electrical Stability ◽  
Solution Processed ◽  
Good Thermal Stability ◽  
Transparent Conducting ◽  
High Flexibility

AbstractNonfullerene organic solar cells (OSCs) have achieved breakthrough with pushing the efficiency exceeding 17%. While this shed light on OSC commercialization, high-performance flexible OSCs should be pursued through solution manufacturing. Herein, we report a solution-processed flexible OSC based on a transparent conducting PEDOT:PSS anode doped with trifluoromethanesulfonic acid (CF3SO3H). Through a low-concentration and low-temperature CF3SO3H doping, the conducting polymer anodes exhibited a main sheet resistance of 35 Ω sq−1 (minimum value: 32 Ω sq−1), a raised work function (≈ 5.0 eV), a superior wettability, and a high electrical stability. The high work function minimized the energy level mismatch among the anodes, hole-transporting layers and electron-donors of the active layers, thereby leading to an enhanced carrier extraction. The solution-processed flexible OSCs yielded a record-high efficiency of 16.41% (maximum value: 16.61%). Besides, the flexible OSCs afforded the 1000 cyclic bending tests at the radius of 1.5 mm and the long-time thermal treatments at 85 °C, demonstrating a high flexibility and a good thermal stability.

scholarly journals Molecular Engineering for High-Performance Fullerene Broadband Photodetector

2021 ◽  
Author(s):  
Mingming Su ◽  
Yajing Hu ◽  
Ao Yu ◽  
Zhiyao Peng ◽  
Wangtao Long ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Low Temperature ◽  
Electron Acceptor ◽  
Photoinduced Electron Transfer ◽  
High Performance ◽  
Organic Molecules ◽  
Low Cost ◽  
Molecular Engineering ◽  
Temperature Requirement ◽  
High Flexibility

Broadband photodetectors fabricated with organic molecules have the advantages of low cost, high flexibility, easy processing and low-temperature requirement. Fullerene molecules, due to the electron acceptor and photoinduced electron transfer...

Application of Combined Casting-Forging Process for Production of Durable Lightweight Aluminum Parts

2013 ◽  
Vol 554-557 ◽  
pp. 264-273 ◽  
Author(s):  
Stanislav Dedov ◽  
Gunter Lehmann ◽  
Rudolf Kawalla
Keyword(s):  
Heat Treatment ◽  
High Performance ◽  
High Strength ◽  
High Energy ◽  
Process Efficiency ◽  
Light Weight ◽  
Technological Chain ◽  
Process Chains ◽  
Coupled Process ◽  
Hardening Heat Treatment

Due to the constant development in the automotive industry, where high performance shared with the maximal comfort and safety at low car body weight are the primary goals, gains the lightweight construction in importance. Materials with light weight, high strength and toughness are being engaged. With this background the material aluminum and its alloys become highly attractive to manufacturers. There are mainly two ways of forming the metal materials: casting or forming. Apart from substitution of one method by another there are also many examples of combining of casting and forging processes in practice. Such approach allows using the advantages of both methods, shortening the process chains and saving energy and resources at the same time. Furthermore the form flexibility can be increased and the product quality can be improved. For higher process efficiency a direct transition from casting to forging operation should be applied, so that the heat loss decreases and no additional heat treatment between these operations is necessary. There are processes known, which allow producing the final parts by casting and forging from one a single heat. The application of such processes requires materials, which have simultaneously good casting and forging properties. The Institute of Metal forming TU Freiberg works intensively on development of combined casting-forging technologies for lightweight aluminum parts. A technological chain for this coupled process followed by precipitation hardening heat treatment was developed (Figure 1). Heat treatable aluminum cast and wrought alloys with 1 – 7 % silicon were applied. By the variation of silicon content the optimal cast, forging and hardening properties were achieved. This technology with high energy efficiency allows producing durable light weight parts from aluminum alloys while the mechanical properties of the final parts are equal to or even higher than those in the conventional processes.

Revisiting the design of LSM-tree Based OLTP storage engine with persistent memory

2021 ◽  
Vol 14 (10) ◽  
pp. 1872-1885
Author(s):  
Baoyue Yan ◽  
Xuntao Cheng ◽  
Bo Jiang ◽  
Shibin Chen ◽  
Canfang Shang ◽  
...  
Keyword(s):  
Recovery Time ◽  
High Performance ◽  
Transaction Processing ◽  
Light Weight ◽  
Global Index ◽  
Persistent Memory ◽  
Write Amplification ◽  
Database As A Service ◽  
Overall Evaluation ◽  
Memory Compaction

The recent byte-addressable and large-capacity commercialized persistent memory (PM) is promising to drive database as a service (DBaaS) into unchartered territories. This paper investigates how to leverage PMs to revisit the conventional LSM-tree based OLTP storage engines designed for DRAM-SSD hierarchy for DBaaS instances. Specifically we (1) propose a light-weight PM allocator named Hal-loc customized for LSM-tree, (2) build a high-performance Semi-persistent Memtable utilizing the persistent in-memory writes of PM, (3) design a concurrent commit algorithm named Reorder Ring to aschieve log-free transaction processing for OLTP workloads and (4) present a Global Index as the new globally sorted persistent level with non-blocking in-memory compaction. The design of Reorder Ring and Semi-persistent Memtable achieves fast writes without synchronized logging overheads and achieves near instant recovery time. Moreover, the design of Semi-persistent Memtable and Global Index with in-memory compaction enables the byte-addressable persistent levels in PM, which significantly reduces the read and write amplification as well as the background compaction overheads. The overall evaluation shows that the performance of our proposal over PM-SSD hierarchy outperforms the baseline by up to 3.8x in YCSB benchmark and by 2x in TPC-C benchmark.

ADDITIVE MANUFACTURING OF HIGH-LOADING POLYMER NANOCOMPOSITES WITH MULTISCALE ALIGNMENT

2021 ◽  
Author(s):  
SOYEON PARK ◽  
KUN (KELVIN) FU
Keyword(s):  
Additive Manufacturing ◽  
Polymer Nanocomposites ◽  
High Performance ◽  
Energy Storage Devices ◽  
Storage Devices ◽  
High Productivity ◽  
Macro Scale ◽  
The Matrix ◽  
Multiscale Structures ◽  
Printing Direction

Polymer nanocomposites have advantages in mechanical, electrical, and optical properties compared to individual components. These unique properties of the nanocomposites have attracted attention in many applications, including electronics, robotics, biomedical fields, automotive industries. To achieve their high performance, it is crucial to control the orientation of nanomaterials within the polymer matrix. For example, the electric conductivity will be maximized in the ordered direction of conductive nanomaterials such as graphene and carbon nanotubes (CNTs). Conventional fabrication methods are commonly used to obtain polymer nanocomposites with the controlled alignment of nanomaterials using electric or magnetic fields, fluid flow, and shear forces. Such approaches may be complex in preparing a manufacturing system, have low fabrication rate, and even limited structure scalability and complexity required for customized functional products. Recently, additive manufacturing (AM), also called 3D printing, has been developed as a major fabrication technology for nanocomposites with aligned reinforcements. AM has the ability to control the orientation of nanoparticles and offers a great way to produce the composites with cost-efficiency, high productivity, scalability, and design flexibility. Herein, we propose a manufacturing process using AM for the architected structure of polymer nanocomposites with oriented nanomaterials using a polylactic acid polymer as the matrix and graphite and CNTs as fillers. AM can achieve the aligned orientation of the nanofillers along the printing direction. Thus, it enables the fabrication of multifunctional nanocomposites with complex shapes and higher precision, from micron to macro scale. This method will offer great opportunities in the advanced applications that require complex multiscale structures such as energy storage devices (e.g., batteries and supercapacitors) and structural electronic devices (e.g., circuits and sensors).

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