Patterning hot spot verification using high speed e-beam metrospection with D2DB at foundry high volume manufacturing environment

2021 ◽  
Author(s):  
Fang Wei ◽  
Chenming Zhang ◽  
Honglin Meng ◽  
Zhihao Chu ◽  
Chao Huang ◽  
...  
Keyword(s):  
High Speed ◽  
Hot Spot ◽  
High Volume ◽  
Manufacturing Environment

scholarly journals Study on the High-Speed Milling Performance of High-Volume Fraction SiCp/Al Composites

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4143
Author(s):  
Youzheng Cui ◽  
Shenrou Gao ◽  
Fengjuan Wang ◽  
Qingming Hu ◽  
Cheng Xu ◽  
...  
Keyword(s):  
High Speed ◽  
Large Scale ◽  
Volume Fraction ◽  
Simulation Analysis ◽  
Cutting Temperature ◽  
High Volume ◽  
Cutting Parameters ◽  
High Volume Fraction ◽  
High Wear Resistance ◽  
Element Analysis

Compared with other materials, high-volume fraction aluminum-based silicon carbide composites (hereinafter referred to as SiCp/Al) have many advantages, including high strength, small change in the expansion coefficient due to temperature, high wear resistance, high corrosion resistance, high fatigue resistance, low density, good dimensional stability, and thermal conductivity. SiCp/Al composites have been widely used in aerospace, ordnance, transportation service, precision instruments, and in many other fields. In this study, the ABAQUS/explicit large-scale finite element analysis platform was used to simulate the milling process of SiCp/Al composites. By changing the parameters of the tool angle, milling depth, and milling speed, the influence of these parameters on the cutting force, cutting temperature, cutting stress, and cutting chips was studied. Optimization of the parameters was based on the above change rules to obtain the best processing combination of parameters. Then, the causes of surface machining defects, such as deep pits, shallow pits, and bulges, were simulated and discussed. Finally, the best cutting parameters obtained through simulation analysis was the tool rake angle γ0 = 5°, tool clearance angle α0 = 5°, corner radius r = 0.4 mm, milling depth ap = 50 mm, and milling speed vc= 300 m/min. The optimal combination of milling parameters provides a theoretical basis for subsequent cutting.

scholarly journals Factors affecting aerosol size distribution during various dental procedures

2021 ◽  
Author(s):  
Shruti Choudhary ◽  
Michael J Durkin ◽  
Daniel C Stoeckel ◽  
Heidi M Steinkamp ◽  
Martin H Thornhill ◽  
...  
Keyword(s):  
Particulate Matter ◽  
High Speed ◽  
High Volume ◽  
Routine Care ◽  
Mitigation Strategies ◽  
Aerosol Size Distribution ◽  
Dental Clinic ◽  
Factors Affecting ◽  
Dental Procedures ◽  
The Impact

Objectives: To determine the impact of various aerosol mitigation interventions and establish duration of aerosol persistence in a variety of dental clinic configurations. Methods: We performed aerosol measurement studies in endodontic, orthodontic, periodontic, pediatric, and general dentistry clinics. We used an optical aerosol spectrometer and wearable particulate matter sensors to measure real-time aerosol concentration from the vantage point of the dentist during routine care in a variety of clinic configurations (e.g, open bay, single room, partitioned operatories). We compared the impact of aerosol mitigation strategies [ventilation and high-volume evacuation (HVE)] and prevalence of particulate matter in the dental clinic environment before, during and after high-speed drilling, slow speed drilling and ultrasonic scaling procedures. Results: Conical and ISOVAC HVE were superior to standard tip evacuation for aerosol-generating procedures. When aerosols were detected in the environment, they were rapidly dispersed within minutes of completing the aerosol-generating procedure. Few aerosols were detected in dental clinics, regardless of configuration, when conical and ISOVAC HVE were used. Conclusions: Dentists should consider using conical or ISOVAC HVE rather than standard tip evacuators to reduce aerosols generated during routine clinical practice. Furthermore, when such effective aerosol mitigation strategies are employed, dentists need not leave dental chairs fallow between patients as aerosols are rapidly dispersed. Clinical Significance: ISOVAC HVE is highly effective in reducing aerosol emissions. With adequate ventilation and HVE use, dental fallow time can be reduced to 5 minutes.

Effect of Draw Furnace Geometry on High Speed Optical Fiber Manufacturing

2000 ◽  
Author(s):  
Xu Cheng ◽  
Yogesh Jaluria
Keyword(s):  
Heat Transfer ◽  
Temperature Distribution ◽  
Optimal Design ◽  
Optical Fiber ◽  
High Speed ◽  
Graphite Furnace ◽  
Large Diameter ◽  
High Volume ◽  
Force Balance ◽  
Zonal Method

Abstract The motivation of manufacturers to pursue higher productivity and low costs in the fabrication of optical fibers requires large diameter silica-based preforms drawn into fiber at very high speed. An optimal design of the draw furnace is particularly desirable to meet the need of high-volume production in the optical fiber industry. This paper investigates optical fiber drawing at high draw speeds in a cylindrincal graphite furnace. A conjugate problem involving the glass and the purge gases is considered. The transport in the two regions is coupled through the boundary conditions at the free glass surface. The zonal method is used to model the radiative heat transfer in the glass. The neck-down profile of the preform at steady state is determined by a force balance, using an iterative numerical scheme. Thermally induced defects are also considered. To emphasize the effects of draw furnace geometry, the diameters of the preform and the fiber are kept fixed at 5 cm and 125 μm, respectively. The length and the diameter of the furnace are changed. For the purposes of comparison, a wide domain of draw speeds, ranging from 5 m/s to 20 m/s, is considered, and the form of the temperature distribution at the furnace surface is kept unchanged. The dependence of the preform/fiber characteristics, such as neckdown profile, velocity distribution and lag, temperature distribution and lag, heat transfer coefficent, defect concentration, and draw tension, on the furnace geometry is determined. Based on these numerical results, an optimal design of the draw furnace can be developed.

Extended Time Machine Design using Reconfigurable Computing for Efficient Recording and Retrieval of Gigabit Network Traffic

2012 ◽  
pp. 699-709
Author(s):  
S. Sajan Kumar ◽  
M. Hari Krishna Prasad ◽  
Suresh Raju Pilli
Keyword(s):  
Network Traffic ◽  
Reconfigurable Computing ◽  
High Speed ◽  
Application Programming Interface ◽  
High Volume ◽  
Machine Design ◽  
Input Output ◽  
Time Machine ◽  
Application Programming ◽  
Programming Interface

Till date there are no systems which promise to efficiently store and retrieve high volume network traffic. Like Time Machine, this efficiently records and retrieves high volume network traffic. The bottleneck of such systems has been to capture packets at such a high speed without dropping and to write a large amount of data to a disk quicklt and sufficiently, without impact on the integrity of the captured data (Ref. Cooke.E., Myrick.A., Rusek.D., & Jahanian.F(2006)). Certain hardware and software parts of the operating system (like drivers, input/output interfaces) cannot cope with such a high volume of data from a network, which may cause loss of data. Based on such experiences the authors have come up with a redesigned implementation of the system which have specialized capture hardware with its own Application Programming Interface for overcoming loss of data and improving efficiency in recording mechanisms.

Advanced Turbine Technology Applications Project (ATTAP): Overview, and Ceramic Component Technology Status

1991 ◽  
Author(s):  
Philip J. Haley
Keyword(s):  
High Speed ◽  
High Volume ◽  
Department Of Energy ◽  
High Yield ◽  
Design System ◽  
Ceramic Component ◽  
Forming Process ◽  
Technology Applications ◽  
Ceramic Components ◽  
Monolithic Ceramics

The automotive gas turbine’s (AGT) significant potential payoffs in fuel economy, emissions, and alternate fuels usage continue to motivate development activities worldwide. The U.S. Department of Energy-sponsored, NASA-managed Advanced Turbine Technology Applications Project (ATTAP) focuses on developing critical AGT structural ceramic component technologies. The area of greatest challenge is that of cost-effective, near-net-shape, high-volume, high-yield manufacturing processes. Process physics modeling and Taguchi analyses are affording substantial progress, and new processes are being explored. Laboratory characterization is building a shared materials data base among Allison, Garrett, Government labs, and ceramic manufacturers. General Motors (GM) has logged over 700 test hours with ceramic components in hot gasifier rigs during ATTAP. A key ATTAP milestone was addressed by successfully demonstrating full goal temperature and speed (2500°F rotor inlet at 100% shaft speed) with ceramic components. Fast-fracture ceramic component design tools are well correlated. Although time-dependent data and mechanistic models exist, a validated design system for such phenomena does not, and is a pressing need. Damage tolerance and impact resistance have been substantially addressed through tailored component designs, tougher monolithic ceramics, and increased ceramic strengths. Ceramic turbine rotors are now continuing to run after various substantial impacts, and after chipping damage. Ceramic-ceramic and ceramic-metal interfacing is being addressed by minimizing components’ joints, and by other DOE-sponsored work on joining models, processes, and materials. The extruded regenerator disk is a continuing goal which requires both forming process and materials technology development. Controlling turbine tip clearances and tolerating tip rubs are key technologies. GM has demonstrated clearance control schemes, as well as rotor survivability to high speed/temperature tip rubs. Several noteworthy ceramic materials reflect the rapid progress over the past decade of monolithic ceramics, especially the Si3N4 family. GM forecasts achieving ATTAP engine cyclic durability goals.

scholarly journals Non-Destructive Characterization of Railway Materials and Components with Infrared Thermography Technique

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4077 ◽  
Author(s):  
Jeongguk Kim
Keyword(s):  
Infrared Thermography ◽  
Thermal Imaging ◽  
High Speed ◽  
Hot Spot ◽  
Imaging Techniques ◽  
Brake Disc ◽  
Ir Thermography ◽  
Contact Mode ◽  
Non Destructive Evaluation ◽  
Non Destructive

Infrared (IR) thermography technology is one of the leading non-destructive evaluation (NDE) techniques based on infrared detection. Infrared thermography, in particular, has the advantage of not only being used in non-contact mode but also provides full images, real-time inspection, and relatively fast results. These advantages make it possible to perform thermal imaging analysis of railway materials and/or components, such as brake disc simulation, monitoring of abnormal heat generation, and monitoring of temperature changes, during mechanical tests. This study introduces the current state of research on railway materials and/or components using IR thermography technology. An attempt was made to characterize the deterioration of electrical equipment of diesel electric locomotives using infrared thermal imaging techniques. In addition, surface temperature monitoring was performed during tensile testing of railway steels using a high-speed infrared camera. Damage evolution due to the hot spot generation of railway brake discs was successfully monitored using high-speed IR cameras. In this paper, IR thermal imaging technology, used as a non-destructive evaluation analysis in the railway field, was introduced, and the results of recent research are presented.

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