DETERMINATION AND APPLICATION OF LARSON-MILLER PARAMETER FOR HEAT RESISTANT STEEL 12CrlMoV AND 15CrMo

Based on the analysis and processing on relative empirical formula and data, C-values in Larson-Miller (P) expression, P= T(C + Igt), have determined for pearlitic heat resistant steel 12Cr1MoV and 15CrMo(20.62 and 20.30). The simulation experiments of high temperature aging, heated from 1.5 to 873 hours, have been designed and performed for its verification. And in combination with published information and the present nearly quantitative works, it has further been verified that both the degradations of microstructures and mechanical properties show a good accuracy and practicability using the Larson-Miller parameter with the present determined C-values. Finally, the effects of carbon content on C-value are analyzed by the empirical electron theory of solids and molecules (EET).

VARIATION OF SUBSTRUCTURES OF PEARLITIC HEAT RESISTANT STEEL AFTER HIGH TEMPERATURE AGING

The observations of dislocations, substructures and other microstructural details were conducted mainly by means of transmission electron microscope (TEM) and scanning electron microscope (SEM) for 12CrlMoV pearlitic heat-resistant steel. It is shown that during the high temperature long-term aging, the disordered and jumbled phase-transformed dislocations caused by normalized cooling are recovered and rearranged into cell substructures, and then the dislocation density is reduced gradually. Finally a low density linear dislocation configuration and a stabler dislocation network are formed and ferritic grains grow considerably.

STCF conceptual design report (Volume 1): Physics & detector

The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics community.It is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or higher.The STCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard Model.The STCF project in China is under development with an extensive R&D program.This document presents the physics opportunities at the STCF,describes conceptual designs of the STCF detector system,and discusses future plans for detector R&D and physics case studies.

Prediction of particle size and layer-thickness distributions in a continuous horizontal fluidized-bed coating process

To predict the particle size and layer-thickness distributions(LTDs)in a continuously operated horizontal fluidized-bed granulation process,two alternative models were considered.A one-dimensional two-zone model was proposed,which describes with population-balance equations the particle growth in a spraying zone that is separated from the drying zone.The residence-time distribution(RTD)was calculated from a literature correlation and was coupled with a population-balance model via a tank-in-series model with reflux.A two-dimensional,one-zone population-balance model,which was based directly on the RTD and the feed particle-size distribution(PSD)was also used.Granulation experiments were conducted and analyzed microscopically and with a camera optical device to determine the sample PSDs.LTDs over the particle population were derived from the PSDs and were analyzed directly by micro-computer-tomography.To compare the simulated data with the experimentally determined distributions,the PSDs were converted to LTDs.The good agreement shows that both methods are suitable to determine the PSD from an RTD of an arbitrary granulation process in a horizontal fluidized bed.Improvement appears necessary with regards to the LTD spread.

Emerging trend for LED wafer level packaging

Currently most light emitting diode （LED） components are made with individual chip packaging technology. The main manufacturing processes follow conventional chip-based IC packaging. In the past several years, there has been an uprising trend in the IC industry to migrate from chip-based packaging to wafer level packaging （WLP）. Therefore, there is a need for LEDs to catch up. This paper introduces advanced LED WLP technologies. The contents cover key enabling processes such as preparation of silicon sub-mount wafer, implementation of interconnection, deposition of phosphor, wafer level encapsulation, and their integration. The emphasis is placed on how to achieve high throughput, low cost manufacturing through WLE

Development and application of a modular test system for the HV-CMOS pixel sensor R&D of the ATLAS HL-LHC upgrade

Background High-voltage CMOS is a promising technology for the pixel sensor of tracking detectors in the collider experiments.Extensive studies are being carried out by theATLASCollaboration to investigate the possibility of using theHV-CMOS technology in the HL-LHC upgrade of the ATLAS inner tracker detector.Purpose The CaRIBOu(Control and Readout Itk BOards)is a modular test system developed to test the HV-CMOS pixel sensor prototypes and demonstrators.Methods This test system consists of pixel sensor specific front-end chip boards,a control and readout board(CaR board),a central interface board and the back-end DAQ system.Currently,two DAQ solutions are available for the CaRIBOu system,one is based on the FELIX(front-end link eXchange)readout system and the other is based on the Gigabit Ethernet link.Results Various testbeam experiments have been carried out with the CaRIBOu system since 2015 for the pixel sensors fabricated by the AMS HV-CMOS 180 nm and 350 nm technologies.Conclusion The test results show that this test system is very flexible and could be adapted to the test of different pixel sensors with minimum effort,and the performance meets the testbeam requirements.