High speed, high power density laser-assisted machining of Al-SiC metal matrix composite with significant increase in productivity and surface quality

Electronic devices such as medical instruments implanted in the human body and electronic control units installed in automobiles have a large impact on human life. The electronic circuits in these devices require highly reliable operation. Radiographic testing has recently been in strong demand as a nondestructive way to help ensure high reliability. Companies that use high-density micrometer-scale circuits or lithium-ion batteries require high speed and high magnification inspection of all parts. The authors have developed a new X-ray source supporting these requirements. The X-ray source has a sealed tube with a transmissive target on a diamond window that offers advantages over X-ray sources having a sealed tube with a reflective target. The X-ray source provides high-power-density X-ray with no anode degradation and a longer shelf life. In this paper, the authors will summarize X-ray source classification relevant to electronic device inspection and will detail X-ray source performance requirements and challenges. The paper will also elaborate on technologies employed in the X-ray source including tube design implementations for high-power-density X-ray, high resolution, and high magnification simultaneously; reduced system downtime for automated X-ray inspection; and reduced dosages utilizing quick X-ray on-and-off emission control for protection of sensitive electronic devices.

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Research on a high power density mechanical-electrical-hydraulic regenerative suspension system for high-speed tracked vehicles

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/09544070211061010 ◽

2021 ◽

pp. 095440702110610

Author(s):

Chao Wang ◽

Weijie Zhang ◽

Guosheng Wang ◽

Yong Guo

Keyword(s):

Power Density ◽

High Power ◽

High Speed ◽

Excitation Amplitude ◽

Suspension System ◽

Level Energy ◽

High Power Density ◽

Damping Force ◽

Tracked Vehicles ◽

Energy Regeneration

High power density energy regeneration is one of the effective solutions to solve the contradiction between improving the damping performance and energy consumption of active suspension. The hydraulic commutator is used to realize hydraulic rectification and hydraulic variable speed/pump/motor with few teeth difference gear pairs is used to match the speed, combined with permanent magnet motor power generation and power supply to put forward kilowatt level high power density mechanical-electrical-hydraulic regenerative suspension system for high-speed tracked vehicles. The mathematical model and fluid-solid-thermo-magnetic multiphysics coupling model are built to analyze the damping performance and regenerative characteristics of the system under passive and semi-active working conditions. The simulation results show that the damping force of the system increases with the increase of the road excitation amplitude and the semi-active control can be realized by adjusting the duty cycle with the PWM control rectifier module. The high power density mechanical-electrical-hydraulic regenerative suspension system can realize kilowatt level energy regeneration, and the regenerative efficiency is more than 50% under low-frequency excitation. The temperature rise of the system is low during operation, which is helpful to improve the reliability and service life.

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Investigation of AC Copper and Iron Losses in High-Speed High-Power Density PMSM

2018 XIII International Conference on Electrical Machines (ICEM) ◽

10.1109/icelmach.2018.8507166 ◽

2018 ◽

Cited By ~ 4

Author(s):

Ahmed Al-Timimy ◽

Paolo Giangrande ◽

Michele Degano ◽

Michael Galea ◽

Chris Gerada

Keyword(s):

Power Density ◽

High Power ◽

High Speed ◽

High Power Density ◽

Iron Losses

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Significance of tungsten disulfide on the mechanical and machining characteristics of phosphor bronze metal matrix composite

Advanced Composites Letters ◽

10.1177/2633366x20962496 ◽

2020 ◽

Vol 29 ◽

pp. 2633366X2096249 ◽

Cited By ~ 1

Author(s):

P Sangaravadivel ◽

G Rajamurugan ◽

Prabu Krishnasamy

Keyword(s):

Flexural Strength ◽

Metal Matrix Composite ◽

Matrix Composite ◽

Metal Matrix ◽

High Speed ◽

Spindle Speed ◽

Tungsten Disulfide ◽

Pbmc Sample ◽

High Speed Turning ◽

Machining Characteristics

The phosphor bronze (PB) is widely preferred in various engineering applications due to its high strength, toughness, fine grain size, low coefficient of friction, and better corrosion resistance. The present work is to investigate the effect of tungsten disulfide (WS2) solid lubricant particle reinforcement in the phosphor bronze metal matrix composite (PBMC) through the mechanical and machining characteristics. The different variant of the composite is fabricated using stir casting technique by varying the volume percentage of WS2 particle from 0% to10%. The prepared PBMC samples are subjected to mechanical and machining (boring and high-speed turning) characterizations. The hardness (Brinell hardness) and flexural strength of the composites are examined as per the ASTM standard. The surface roughness (Ra) of the PBMC sample is analyzed through the boring and high-speed turning operations by varying the spindle speed, feed rate, and depth of cut. The scanning electron microscope (SEM) is employed to confirm the uniform dispersion of the reinforcement particle through the microstructural analysis. The presence of WS2 particles and other ingredients is ensured by X-ray diffraction analysis in the composites. The influence of WS2 reinforcement particles on tool life is analyzed on the PBMC4 (PBMC with 8% WS2) with the predefined machining parameters in the high-speed turning operation. The increase in WS2 particle (0–10%) improves the hardness (11.85%) and flexural strength in PBMC4 as compared to PBMC1 (PBMC with 0% WS2). At a higher spindle speed (1200 r/min), the Ra is reduced in PBMC1 as compared to 900 r/min, whereas the rest of the PBMC sample show higher surface irregularity at 1200 r/min.

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