A. Suplicz

43761558700

Publications - 4

Enhanced injection molding simulation of advanced injection molds

N. K. Kovács A. Suplicz J. G. Kovács T. Tábi B. Zink István Hatos H. Hargitai F. Szabó

Publication Name: Polymers

Publication Date: 2017-01-01

Volume: 9

Issue: 2

Page Range: Unknown

Description:

The most time-consuming phase of the injection molding cycle is cooling. Cooling efficiency can be enhanced with the application of conformal cooling systems or high thermal conductivity copper molds. The conformal cooling channels are placed along the geometry of the injection-molded product, and thus they can extract more heat and heat removal is more uniform than in the case of conventional cooling systems. In the case of copper mold inserts, cooling channels are made by drilling and heat removal is facilitated by the high thermal conductivity coefficient of copper, which is several times that of steel. Designing optimal cooling systems is a complex process; a proper design requires injection molding simulations, but the accuracy of calculations depends on how precise the input parameters and boundary conditions are. In this study, three cooling circuit designs and three mold materials (Ampcoloy 940, 1.2311 (P20) steel, and MS1 steel) were used and compared using numerical methods. The effect of different mold designs and materials on cooling efficiency were examined using calculated and measured results. The simulation model was adjusted to the measurement results by considering the joint gap between the mold inserts.

Open Access: Yes

DOI: 10.3390/polym9020077

Methodology development for through-plane thermal conductivity prediction of composites

A. Suplicz J. G. Kovács H. Hargitai

Publication Name: International Journal of Thermal Sciences

Publication Date: 2016-02-01

Volume: 100

Issue: Unknown

Page Range: 54-59

Description:

The prediction and tailoring of thermal conductivity of two-phase composites is essential. In this work a new semi-empirical model was developed, which was derived from the rule of mixtures. Furthermore, a new methodology was developed to determine the thermal conductivity of the fillers and the maximum achievable filler content. To validate the new model, polypropylene-based composites were prepared with different fillers, such as talc, boron-nitride and graphite, with 20, 40 and 60 vol% filler content. The results obtained from the proposed model are in good agreement with the experimental data. Various other theoretical models were also introduced and compared to the experiments, but in most cases those underestimate or overestimate the thermal conductivity of composites.

Open Access: Yes

DOI: DOI not available

Thermal simulations and measurements for rapid tool inserts in injection molding applications

N. K. Kovács A. Suplicz J. G. Kovács T. Tábi B. Zink H. Hargitai F. Szabó

Publication Name: Applied Thermal Engineering

Publication Date: 2015-06-25

Volume: 85

Issue: Unknown

Page Range: 44-51

Description:

apid prototyping (RP) is a widely used process in the industry to shorten development time. Another advantage of this technology is the ability to create conformal cooling systems, thus not only cooling time and cycle time can be shortened, but also shrinkage, thus warpage can be decreased. The main disadvantage of Rapid prototyping materials is their low thermal conductivity, which strongly influences cooling properties and warpage. The research based on a special developed injection mold for novel rapid prototyping based mold inserts with cooling systems. A method has been introduced to determine the most important thermal parameters for injection molding simulations using rapid tools. Those parameters, which can be measured such as the specific heat and thermal conductivity of the mold materials, are directly implemented into the software. The heat transfer coefficient between the polymer melt and the rapid tool insert surface cannot be measured in a reasonable way, thus simulation software was used to determine that based on indirect calculation derived from real measurements. In the paper, the method was proved with Fused Deposition Modeling (FDM) and Polyjet mold inserts.

Open Access: Yes

DOI: 10.1016/j.applthermaleng.2015.03.075

The analysis of injection molding defects caused by gate vestiges

N. K. Kovács A. Suplicz J. G. Kovács T. Tábi B. Zink H. Hargitai F. Szabó

Publication Name: Express Polymer Letters

Publication Date: 2015-04-01

Volume: 9

Issue: 4

Page Range: 394-400

Description:

Issues of product safety are the most serious problems of an injection molded product due to their risk to human health. Such a safety problem can be the needle-shaped vestige at the gate zone of injection molded products, called a gate vestige. Only observations of the formation of gate vestiges can be found in the literature, but the processing parameters influencing their dimensions, especially their height have not been studied yet. Our goal was to study the effect of various injection molding processing parameters and gate constructions on gate vestige formation.

Open Access: Yes

DOI: 10.3144/expresspolymlett.2015.37