Next Article in Journal
Low Resistance TiO2/p-Si Heterojunction for Tandem Solar Cells
Previous Article in Journal
Utilization of Polypropylene in the Production of Metal-Filled Polymer Composites: Development and Characteristics
Open AccessArticle

External Gas-Assisted Mold Temperature Control Improves Weld Line Quality in the Injection Molding Process

1
Faculty of Mechanical Engineering, HCMC University of Technology and Education, Ho Chi Minh City 71307, Vietnam
2
Department of Manufacturing Engineering, Faculty of Mechanical Engineering, University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City 72506, Vietnam
3
Vietnam National University, Ho Chi Minh City 71300, Linh Trung Ward, Thu Duc District, Vietnam
*
Author to whom correspondence should be addressed.
Materials 2020, 13(12), 2855; https://doi.org/10.3390/ma13122855
Received: 27 May 2020 / Revised: 20 June 2020 / Accepted: 23 June 2020 / Published: 25 June 2020
(This article belongs to the Special Issue Advances in Injection Molding for Polymer Processing)
Simulations and experiments were conducted with gas temperatures of 200–400 °C to investigate the impact of external gas-assisted mold temperature control (Ex-GMTC) on the quality of weld line of molding products. In the heating step, the heating rate was 19.6 °C/s from 30 to 128.5 °C in the first 5 s in a 400 °C gas environment. When applied to heating the weld line area of an injection mold, Ex-GMTC improved the appearance of the weld line when the cavity temperature was preheated to 150 °C. For the tensile strength test, a melt flow simulation comparing the packing pressure of different mesh thicknesses revealed that Ex-GMTC helped maintain a high pressure in the weld line area in different packing periods. This was verified by an experiment where Ex-GMTC was applied with 400 °C gas to change the mesh area temperature. The result indicated that an increase in the weld line area temperature from 60 to 180 °C improves the tensile strength of all mesh thicknesses, which was more pronounced with thinner parts, especially at 0.4 mm. The simulations revealed that high temperature is concentrated in the weld line area of the cavity surface, thus reducing the energy wasted during heating. View Full-Text
Keywords: injection molding; thin wall injection molding; mold temperature control; external gas-assisted mold temperature control (Ex-GMTC); weld line appearance; weld line strength injection molding; thin wall injection molding; mold temperature control; external gas-assisted mold temperature control (Ex-GMTC); weld line appearance; weld line strength
Show Figures

Figure 1

MDPI and ACS Style

The Uyen, T.M.; Truong Giang, N.; Do, T.T.; Anh Son, T.; Son Minh, P. External Gas-Assisted Mold Temperature Control Improves Weld Line Quality in the Injection Molding Process. Materials 2020, 13, 2855.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop