Inspection of Water Cooling on Plastics Molding Process using 3D-printed Metallic Mold

Abstract This paper reports on design, fabrication, and kinematics modeling of a 3D printed soft parallel robot equipped with soft pneumatic actuators. Soft robotics is an emerging field of research which facilitates safe human machine interface. Soft elastomeric actuators made through molding process are one of the key elements of soft robotic systems. However, molding process is tedious and time consuming making the fabrication process undesirable. Recently reported 3D printed soft pneumatic actuators pave the way for manufacturing of novel soft actuators and robots with complex geometries. The current work can be considered as a proof of concept for 3D printing of a soft parallel robot. The robot consists of two soft pneumatic actuators that are connected to two passive links by mean of flexible hinges. The robot has two degrees of freedom and can be used in planar manipulation tasks. Moreover, a number of robots can be configured to operate in a cooperative manner to increase the manipulation dexterity. A kinematic model is developed to simulate the motion of robot end-effector. Through application of the kinematic model it has been shown that the robot is capable of following any planar trajectories within its workspace. Also, pseudo-rigid-body model (PRBM) is used to develop a dynamic model of the soft robot to more accurately predict the robot interaction with its environment and also develop advanced control system for robust position control of the robot.

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Study of Mechanical Properties of 3D Printed Material for Non-Pneumatic Tire Spoke

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.880.97 ◽

2021 ◽

Vol 880 ◽

pp. 97-102

Author(s):

Ravivat Rugsaj ◽

Chakrit Suvanjumrat

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Elastic Material ◽

Molding Process ◽

Breaking Strain ◽

Pneumatic Tire ◽

Wide Range ◽

Printing Technique ◽

3D Printed ◽

3D Printing Technique

The spokes of airless tire or non-pneumatic tire (NPT) are normally made with thermoplastic polyurethane (TPU), which is highly elastic material, to replace inflation pressure in conventional pneumatic tire. However there are limitation in designing of complex spoke geometries due to difficulty in manufacturing process, which normally involve molding process. Recently, the 3D printing technique has been improved and can be used to create highly complex geometries with wide range of materials. However the mechanical properties of printed spoke structure using 3D printing technique are still required to design and development of NPT. This research aim to study the mechanical properties of TPU while varying in printing conditions. The specimens were prepared from actual NPT spoke using waterjet cutting technique and 3D printing technique according to the testing standard ASTM D412 and D638, respectively. The tensile tests were performed on the specimens with corresponding crosshead speed. The testing speed of 3D printed specimen were also varied to 100 and 200 mm/min to study the effects of strain rate on mechanical properties. The stress-strain relationships were obtained from tensile testing and the important mechanical properties were then evaluated. The mechanical properties of specimens prepared from actual NPT spokes and 3D printed specimens were then compared. The ultimate stress of specimens prepared from actual NPT spokes in radial direction and 3D printed specimens with 100% infill were found to be 32.92 and 25.47 MPa, respectively, while the breaking strain were found to be 12.98 and 10.87, respectively. Thus, the information obtained from this research can be used to ensure the possibility in creating NPT spoke using 3D printing technique based on elastic material such as TPU.

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Performance Analysis of Enhanced 3D Printed Polymer Molds for Metal Injection Molding Process

Metals ◽

10.3390/met8060433 ◽

2018 ◽

Vol 8 (6) ◽

pp. 433 ◽

Cited By ~ 7

Author(s):

Khurram Altaf ◽

Junaid Qayyum ◽

A. Rani ◽

Faiz Ahmad ◽

Puteri Megat-Yusoff ◽

...

Keyword(s):

Performance Analysis ◽

Injection Molding ◽

Metal Injection Molding ◽

Injection Molding Process ◽

Molding Process ◽

3D Printed

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Improving the Performance of 3D Printed Molds for Plastic Injection Molding

10.29007/9dk4 ◽

2019 ◽

Author(s):

Faryar Etesami ◽

Christopher Mullens ◽

Ramsey Sahli ◽

Trey Webb

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Injection Molding ◽

Surface Hardness ◽

Plastic Injection Molding ◽

Injection Molding Process ◽

Molding Process ◽

High Temperature Mechanical Properties ◽

3D Printed ◽

Plastic Injection

Additive manufacturing technology has become a viable solution for making molds for plastic injection molding applications. The molds are usually made of high temperature plastic resins suitable for plastic injection molding. Molding resins have superior mechanical properties necessary to withstand the high temperatures and pressures of the injection molding process. It is known that high temperature mechanical properties of resins influence mold performance but it is not established which properties are most important and to what extent they influence the mold performance. Identifying the most important properties influencing mold performance would help resin manufacturers to develop better mold-making materials. In order to study the performance of mold materials we have built a device for measuring the mechanical properties of 3D printed resins including their strength, surface hardness, and wear resistance at molding temperatures of up to 260 oC. We then quantified the mechanical properties of three high-temperature resins along with ABS at the injection molding temperatures. This paper describes the test device and the results of characterizing the mechanical properties of the selected plastics.

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Metal Injection Molding Process Parameters as A Function of Filling Performance of 3D Printed Polymer Mold

MATEC Web of Conferences ◽

10.1051/matecconf/201822506004 ◽

2018 ◽

Vol 225 ◽

pp. 06004

Author(s):

Junaid A. Qayyum ◽

Khurram Altaf ◽

A. Majdi A. Rani ◽

Faiz Ahmad ◽

Hafiz A. Qadir ◽

...

Keyword(s):

Injection Molding ◽

Metal Injection Molding ◽

Injection Molding Process ◽

Metal Mold ◽

Molding Process ◽

Injection Parameters ◽

3D Printed ◽

Low Volume ◽

Parts Manufacturing ◽

Polymer Mold

Metal injection molding (MIM) is a swift manufacturing process, which can produce complex and intricate parts with good repeatability and accuracy. However, to quickly address low-volume demands of customized MIM parts, manufacturing of mold could be a potential challenge. Typically, machined metal molds are used for MIM, but they are expensive and need more lead time. The machined metal mold becomes useless once the design is changed or requirement of MIM parts is met. Therefore, for MIM production of a low volume of highly customized parts, machined metal mold could be substituted by 3D printed polymer molds. However, knowledge of filling behavior of MIM feedstock in polymer mold is a grey area, which demands study to investigate the effects of injection parameters on mold filling. The present study investigates the effects of machine injection parameters on feedstock filling behavior in 3D printed polymer molds. An attempt has been made to determine the trend of feedstock filling in the polymer mold as a function of injection parameters. Further, the design of experiment (DOE) has been used to estimate the weight of injection parameters.

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Nucleation and Early Growth of Sputtered thin Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069570 ◽

1970 ◽

Vol 28 ◽

pp. 516-517

Author(s):

Dudley M. Sherman ◽

Thos. E. Hutchinson

Keyword(s):

Thin Films ◽

Electron Beam ◽

Ion Beam ◽

Ion Source ◽

Water Cooling ◽

Stages Of Growth ◽

Lens Assembly ◽

Microscope Technique ◽

Ion Beam Sputter Deposition

The in situ electron microscope technique has been shown to be a powerful method for investigating the nucleation and growth of thin films formed by vacuum vapor deposition. The nucleation and early stages of growth of metal deposits formed by ion beam sputter-deposition are now being studied by the in situ technique.A duoplasmatron ion source and lens assembly has been attached to one side of the universal chamber of an RCA EMU-4 microscope and a sputtering target inserted into the chamber from the opposite side. The material to be deposited, in disc form, is bonded to the end of an electrically isolated copper rod that has provisions for target water cooling. The ion beam is normal to the microscope electron beam and the target is placed adjacent to the electron beam above the specimen hot stage, as shown in Figure 1.

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