Characterization of deformation in injection molded parts after packing and cooling

1999 ◽  
Vol 148 (1) ◽  
pp. 263-283 ◽  
Author(s):  
Jung Hoon Jung ◽  
Seok Won Lee ◽  
Jae Ryoun Youn
Keyword(s):  
Molded Parts ◽  
Injection Molded

Characterization of Injection-Molded Parts with Carbon Black-Filled Polymers

2012 ◽  
pp. 483-513 ◽  
Author(s):  
Volker Piotter ◽  
Jürgen Prokop ◽  
Xianping Liu
Keyword(s):  
Carbon Black ◽  
Filled Polymers ◽  
Molded Parts ◽  
Injection Molded

Warpage Characterization of Thin and Centrally-Gated Injection Molded Part by Applying Cavity Pressure Measurement

2013 ◽  
Vol 446-447 ◽  
pp. 1099-1103 ◽  
Author(s):  
H. Zamani ◽  
S. Azmoudeh ◽  
K. Shelesh-Nezhad
Keyword(s):  
Radial Flow ◽  
Mold Temperature ◽  
Cavity Pressure ◽  
Injection Speed ◽  
Molded Part ◽  
Pressure Time ◽  
Molded Parts ◽  
Injection Molded ◽  
Thin Disks

Two types of injection molded parts including parts with thin shell feature and parts molded with radial flow pattern are highly susceptible to the warpage. In this research, the warpage performance of a thin and centrally-gated disk was experimentally investigated. The melt pressure-time traces of two different locations inside the mold cavity were monitored by employing piezoelectric transducers. The results indicated that the pressure difference magnitude of melt at two locations along the radial flow path is related to the extent of molded part deformation. Moreover, it was pointed out that the high magnitude of warpage is because of two conflicting actions in the molded part comprising expansion as a result of viscoelastic recovery in the central region, and thermal contraction in the edge region of the thin disk. The molding variables encompassing injection speed, holding pressure, back pressure, mold temperature and screw rotational speed affected the thin disks deformation in order of significance.

A Study on the Birefringence Measurement in Injection Molded Parts Using Two Different Laser Sources and R-G-B Separation of White Light

2006 ◽  
Vol 326-328 ◽  
pp. 187-190
Author(s):  
Jong Sun Kim ◽  
Chul Jin Hwang ◽  
Kyung Hwan Yoon
Keyword(s):  
White Light ◽  
Low Cost ◽  
Main Idea ◽  
Injection Molding Process ◽  
Molding Process ◽  
Laser Method ◽  
High Productivity ◽  
Molded Parts ◽  
Injection Molded ◽  
Plastic Parts

Recently, injection molded plastic optical products are widely used in many fields, because injection molding process has advantages of low cost and high productivity. However, there remains residual birefringence and residual stresses originated from flow history and differential cooling. The present study focused on developing a technique to measure the birefringence in transparent injection-molded optical plastic parts using two methods as follows: (i) the two colored laser method, (ii) the R-G-B separation method of white light. The main idea of both methods came from the fact that more information can be obtained from the distribution of retardation caused by different wavelengths. The comparison between two methods is demonstrated for the same sample of which retardation is up to 850 nm.

scholarly journals Silane-Functionalized Sheep Wool Fibers from Dairy Industry Waste for the Development of Plasticized PLA Composites with Maleinized Linseed Oil for Injection-Molded Parts

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2523
Author(s):  
Franciszek Pawlak ◽  
Miguel Aldas ◽  
Francisco Parres ◽  
Juan López-Martínez ◽  
Marina Patricia Arrieta
Keyword(s):  
Linseed Oil ◽  
Microstructural Analysis ◽  
Dairy Industry ◽  
Poly Lactic Acid ◽  
Industry Waste ◽  
Wool Fibers ◽  
Molded Parts ◽  
Silane Modification ◽  
Injection Molded ◽  
Sheep Wool

Poly(lactic acid) (PLA) was plasticized with maleinized linseed oil (MLO) and further reinforced with sheep wool fibers recovered from the dairy industry. The wool fibers were firstly functionalized with 1 and 2.5 phr of tris(2-methoxyethoxy)(vinyl) (TVS) silane coupling agent and were further used in 1, 5, and 10 phr to reinforce the PLA/MLO matrix. Then, the composite materials were processed by extrusion, followed by injection-molding processes. The mechanical, thermal, microstructural, and surface properties were assessed. While the addition of untreated wool fibers to the plasticized PLA/MLO matrix caused a general decrease in the mechanical properties, the TVS treatment was able to slightly compensate for such mechanical losses. Additionally, a shift in cold crystallization and a decrease in the degree of crystallization were observed due to the fiber silane modification. The microstructural analysis confirmed enhanced interaction between silane-modified fibers and the polymeric matrix. The inclusion of the fiber into the PLA/MLO matrix made the obtained material more hydrophobic, while the yellowish color of the material increased with the fiber content.

scholarly journals Development of a novel color inhomogeneity test method for injection molded parts

2014 ◽  
Vol 37 ◽  
pp. 112-116 ◽  
Author(s):  
L. Zsíros ◽  
A. Suplicz ◽  
G. Romhány ◽  
T. Tábi ◽  
J.G. Kovács
Keyword(s):  
Test Method ◽  
Molded Parts ◽  
Injection Molded

Prediction and measurement of residual stresses in injection molded parts

2001 ◽  
Vol 2 (4) ◽  
pp. 203-211 ◽  
Author(s):  
Young Il Kwon ◽  
Tae Jin Kang ◽  
Kwansoo Chung ◽  
Jae Ryoun Youn
Keyword(s):  
Residual Stresses ◽  
Molded Parts ◽  
Injection Molded

Geometry-Based Index for Predicting Sink Mark in Plastic Parts

1991 ◽  
Author(s):  
Kurt Beiter ◽  
Kosuke Ishii ◽  
Lee Hornberger
Keyword(s):  
Process Conditions ◽  
Plastic Part ◽  
Design Rules ◽  
Packing Pressure ◽  
Molded Parts ◽  
Injection Molded ◽  
Form Features ◽  
Plastic Parts ◽  
Sink Mark

Abstract This paper describes the development of geometry-based indices that predict sink mark depth in injection molded parts. Plastic part designers need such indices to incorporate manufacturability concerns at the conceptual stage of design. These indices apply to several form features so engineers do not have to check different design rules for each geometry element. First, we propose a geometry-based sink index that can be used to predict sink mark depth as a function of process conditions such as packing pressure. Next, we explain how this relationship is identified through experiments. We also describe HyperDesign/Plastics, a Macintosh-based design aid that incorporates the sink index.

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