scholarly journals Fast mold surface temperature evolution: Challenges and opportunities

2019 ◽  
Author(s):  
S. Liparoti ◽  
A. Sorrentino ◽  
V. Speranza ◽  
R. Pantani ◽  
G. Titomanlio
RSC Advances ◽  
2015 ◽  
Vol 5 (46) ◽  
pp. 36434-36448 ◽  
Author(s):  
S. Liparoti ◽  
A. Sorrentino ◽  
G. Guzman ◽  
M. Cakmak ◽  
G. Titomanlio

It is widely accepted that mold temperature has a strong effect on the amount of molecular orientation and morphology developed in a non-isothermal flowing melt.


2016 ◽  
Author(s):  
Sara Liparoti ◽  
Andrea Sorrentino ◽  
Gustavo Guzman ◽  
Mukerrem Cakmak ◽  
Giuseppe Titomanlio

Author(s):  
Byoung Hee You ◽  
Daniel S. Park ◽  
Christopher W. Mock ◽  
Wilfredo M. Caceres ◽  
Dimitris E. Nikitopoulos ◽  
...  

Simulations and experiments to assess the predictability of dimensional and locational tolerances of passive alignment structures on injection molded microfluidic components were performed. A center-gated disk with microscale assembly features, to aid metrology, was reproduced using injection molding. The feature dimensions were 100, 200, 300, and 400 μ. Dimensions of the features were measured using optical profilometery and optical microscopy. Simulations using a commercial package overestimated replication fidelity. Mold surface temperatures and injection speeds significantly affected the replication fidelity as the ratio of surface area to volume increased. The location of better replication fidelity, at each mold surface temperature, moved from the edge of the mold cavity to the injection point as the mold surface temperature increased from 100°C to 150°C. Therefore, process parameters and the design of a mold have to be considered for successful replication of the features.


2008 ◽  
Vol 21 (5) ◽  
pp. 1104-1121 ◽  
Author(s):  
Sergey Kravtsov ◽  
Christopher Spannagle

Abstract This study identifies interdecadal natural climate variability in global surface temperatures by subtracting, from the observed temperature evolution, multimodel ensemble mean based on the World Climate Research Programme's (WCRP) Coupled Model Intercomparison Project phase 3 (CMIP3) multimodel dataset. The resulting signal resembles the so-called Atlantic multidecadal oscillation (AMO) and is presumably associated with intrinsic dynamics of the oceanic thermohaline circulation (THC). While certain phases of the oscillation are dominated by the anomalies in the North Atlantic region, other phases are characterized by global teleconnections to the North Pacific Ocean, tropical Atlantic Ocean, as well as the Southern Ocean. In particular, natural variability of sea surface temperature in the Atlantic hurricanes’ main development region has a peak-to-peak amplitude comparable in magnitude to this region’s surface temperature increase over the past century, for all seasons. Evidence suggests that the AMO influence on secular trends in the global-mean surface temperature can arise via direct, regional contribution to the surface temperature evolution, as well as via an indirect route linked to variability of the oceanic uptake of CO2 associated with AMO-related THC changes.


Soft Matter ◽  
2020 ◽  
Vol 16 (41) ◽  
pp. 9568-9577
Author(s):  
Lu Shen ◽  
Junheng Ren ◽  
Fei Duan

Controlled ethanol droplet evaporation shows a five-phase surface temperature evolution and two transitions among the three radial surface temperature distributions.


Author(s):  
Masataka Kosaka ◽  
Yoshio Fukushima

Abstract Hydrogen is expected to become one of the major secondary energy sources and to be treated as important as conventional secondary energy such as electrical energy, thermal energy and so on. Effectively, to use the hydrogen energy leads to the achievement of the low carbon society that is one of the goals of the sustainable society that is aim at the modern society. However, in the industry, there are few precedents of practical use that is using hydrogen energy. In this study, hydrogen energy is applied to plastic injection molding mold heating using LmNi4.90Mn0.10 hydride. In this paper, the thermal characteristic of heating and cooling processes of the proposal system with using the heat of formations by exothermic/endothermic reversible reactions was investigated and the effectiveness of this method has been evaluated from relationship between measured surface temperature change and amount of hydrogen absorption. As results, using this proposal system, when the time cycle of the heating and cooling processes was set about 162 seconds, the mold surface temperature difference of the heating system between these processes became 55 K and the average amount of hydrogen transfer of three cycles except for first cycle was 0.80g which was 80% value of maximum amount of hydrogen absorption.


Author(s):  
Shia-Chung Chen ◽  
Yaw-Jen Chang ◽  
Jen-An Chang ◽  
Hsin-Shu Peng ◽  
Ying-Chieh Wang

Dynamic mold surface temperature control (DMTC) has the advantage of improving molded part qualities without significant increases in cycle time. A gas-assisted heating system combined with water cooling was developed to achieve DMTC for injection molding. With gas-assisted heating, it takes 2s for the mold surface temperature to vary from 60 °C to 120 °C whereas it requires 186s using water heating. Further, it takes 21s and 84s for the mold surface to cool to 60 °C under gas heating and water heating, respectively. The gas-assisted heating system also shows excellent efficiency for micro injection molding of biochips to achieve high replication accuracy of the micro channels.


2016 ◽  
Author(s):  
S. Liparoti ◽  
V. Speranza ◽  
R. Pantani ◽  
G. Titomanlio

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