Simulation of radiative-conductive heating of semitransparent layer on semi-infinite substrate

Author(s):  
Ayal M. Timofeev ◽  
Oleg N. Zhirkov
Author(s):  
O Kocar ◽  
H Livatyalı

An aluminized 22MnB5 (Boron) steel sheet, used for structural parts in the automotive industry, was subjected to press-hardening followed by austenitizing, both in a conventional furnace and via the conductive (electric resistance) heating method, an innovative technique based on the Joule’s principle for fast heating of the sheet metal. Conductive heating presents a number of advantages over the in-furnace heating method. These include a more efficient use of energy, as well as the requirement of less time and space for heating, thus lowering costs. After press-hardening was performed using both methods, the microstructural and mechanical characterizations of both specimens were examined for optical microscopy, hardness, tensile strength, and high-speed impact tests. The results showed that the press-hardening process transformed the ferritic–pearlitic microstructure in the as-received state into martensite after die quenching and caused a substantial increase in hardness and strength at the expense of ductility and impact toughness. On the other hand, no significant difference was observed in either the microstructure or mechanical properties with respect to the heating method used. The results obtained in the present investigation concur with the findings of current literature.


2018 ◽  
Author(s):  
S. Romanenko ◽  
A. R. Harvey ◽  
L Hool ◽  
R. Begley ◽  
S. Fan ◽  
...  

AbstractDue to new applications such as wireless communications, security scanning, and imaging the presence of artificially generated high frequency (30-300 GHz) millimetre-wave (MMW) signals in the environment is increasing. Although safe exposure levels have been set by studies involving direct thermal damage to tissue, there is evidence that MMWs can have an impact on cellular function, including neurons. Earlier in vitro studies have shown that exposure levels well below the recommended safe limit of 1mW/cm2 cause changes in the action potential (AP) firing rate, resting potential, and AP pulse shape of sensory neurons in leech preparations, as well as alter neuronal properties in rat cortical brain slices; these effects differ from changes induced by direct heating. In this paper we examine continuous MMW power (up to 80 mW/cm2 at 60 GHz) and evaluate the responses in the thermosensitive primary nociceptors of the medicinal leech (genus Richardsonianus Australis). The results show that MMW exposure causes an almost two-fold decrease in the threshold for activation of the AP compared with conductive heating (3.6±0.4 mV vs. 6.5±0.4 mV respectively). Our analysis suggests that MMW exposure mediated threshold alterations are not caused by enhancement of voltage gated sodium and potassium conductance. Moreover, it appears that MMW exposure has a modest suppressing effect on membrane excitability. We propose that the reduction in AP threshold can be attributed to sensitization of the TRPV1-like receptor in the leech nociceptor. In silico modelling supported the experimental findings. Our results provide evidence that MMW exposure stimulates specific receptor responses that differ from direct conductive heating, fostering the need for additional studies.


2019 ◽  
Vol 142 ◽  
pp. 111865 ◽  
Author(s):  
Narendra Kumar ◽  
Pranjali D Muley ◽  
Dorin Boldor ◽  
Gary G Coty ◽  
Joan G Lynam

2016 ◽  
Vol 7 (2) ◽  
pp. 297-301 ◽  
Author(s):  
Elden T. Garrett ◽  
Yiwen Pei ◽  
Andrew B. Lowe

A comparative study of microwave-assisted (MA) and conductive heating in RAFT dispersion polymerization formulations in MeOH that result in polymerization-induced self-assembly is detailed.


2018 ◽  
Vol 78 (4) ◽  
pp. 1913-1930
Author(s):  
Yuting Huang ◽  
Immaculada Iglesias ◽  
Antonio L. Sánchez
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document