Applying Isothermal Injection Moulding Process in the Manufacturing of Polymer Composite Reinforced with NiTi Shape Memory Alloy

2017 ◽  
Vol 380 ◽  
pp. 212-217 ◽  
Author(s):  
C.A. Araújo Mota ◽  
C.J. Araújo ◽  
A.G. Barbosa de Lima ◽  
Tony Herbert Freire de Andrade ◽  
D. Silveira Lira
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Product Quality ◽  
Polymer Composite ◽  
Smart Materials ◽  
Low Cost ◽  
Injection Pressure ◽  
Niti Shape Memory Alloy ◽  
Moulding Process ◽  
Injection Moulding Process

SMART materials have gained several applications in industries, especially aeronautical and biomedical. Therefore, the fabrication process of these materials must present quality in the completion and dimensioning, in addition to well established mechanical properties. In this sense, the Resin Transfer Molding (RTM) process is presented as an alternative to the manufacture of such products. This process presents advantages compared to other methods, such as, product quality and low cost. Thus, this work aims to model and simulate numerically the manufacturing process of polymer composite reinforced with NiTi shape memory alloy by RTM using the Ansys CFX commercial software. Results of pressure, velocity and volume fractions fields of the phases are presented and discussed. It was verified that the process parameters, like injection pressure and resin inlet and air outlet positions influenced the total time of the process and final product quality.

An Ablation Parameter Study and Micromachining of NiTi Based Shape Memory Alloy Using Femtosecond Laser

2007 ◽  
Author(s):  
Nitin Uppal ◽  
Panos S. Shiakolas
Keyword(s):  
Shape Memory Alloy ◽  
Femtosecond Laser ◽  
Shape Memory ◽  
Smart Materials ◽  
Interaction Mechanism ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Niti Shape Memory Alloy ◽  
Parameter Study ◽  
New Applications

The use of femtosecond lasers for the micromachining of engineering materials with micro and submicron size features is slowly but steadily increasing. This increase though presents challenges in understanding the interaction mechanism of femtosecond laser pulses with a material and defining process parameters for quality machining. This manuscript will present the setup for a 3DOF femtosecond laser microfabrication (FLM) system and its use in studying the ablation (single and multi shot) characteristics and incubation coefficient of nickel-titanium (NiTi) shape memory alloy. Understanding of these characteristics could allow for the identification of new applications of smart materials in the macro, micro, nano and MEMS domains.

scholarly journals OPTIMIZATION OF NICKEL CONTENT ON SOME PROPERTIES OF (NITI) SHAPE MEMORY ALLOY

2020 ◽  
Vol 1 (01) ◽  
pp. 40-47
Author(s):  
Aissa Bouaissi ◽  
Nabaa S Radhi ◽  
Karrar F. Morad ◽  
Mohammad H. Hafiz ◽  
Alaa Abdulhasan Atiyah
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Smart Materials ◽  
Shape Recovery ◽  
Fatigue Behavior ◽  
Nickel Content ◽  
Functionally Graded ◽  
Niti Shape Memory Alloy ◽  
Shape Effect ◽  
The Impact

Shape Memory Alloys (SMAs) are one of the most hopeful smart materials, especially, Nickel–Titanium (NiTi or Nitinol). These alloys are great and desirable due to their excellent reliability and behavior among all the commercially available alloys. In addition, strain recovery, (Ni–Ti) is granulated for a wide variety of medical uses because of its favorite properties such as fatigue behavior, corrosion resistance and biocompatibility. This paper explores the creation and the characterization of functionally graded (NiTi) materials. This work demonstrations the impact of Nickel contains changes on the characteristics of NiTi shape memory alloy, in order to obtain the suitable addition of Nickel contain, which gives the optimal balance between hardness, start and finish martensitic point, shape recovery and shape effect of alloys properties. These materials are prepared to obtain suddenly or gradually microstructure or composition differences inside the structure of one piece of material, the specimens made by powder metallurgy process and the influence of every layer of composite by; micro-hardness, transformation temperature DSC and shape effect. The hardness value and shape recovery decrease with increase nickel content. superior shape memory effect (SME) and shape recovery (SR) properties (i.e., 8.747, 10.270 for SMA-FGM1 SMA-FGM2 respectively, and SR is 1.735, 2.977 for SMA-FGM1 SMA-FGM2) respectively.  

Micromachining Characteristics of NiTi Based Shape Memory Alloy Using Femtosecond Laser

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
Nitin Uppal ◽  
Panos S. Shiakolas
Keyword(s):  
Shape Memory Alloy ◽  
Femtosecond Laser ◽  
Shape Memory ◽  
Smart Materials ◽  
Morphological Changes ◽  
Wide Spectrum ◽  
Interaction Mechanism ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Niti Shape Memory Alloy

Femtosecond laser micromachining (FLM) is a relatively new and promising technology for the micromachining of a wide spectrum of engineering materials with micron and submicron size features. The interaction mechanism of femtosecond laser pulses with matter is not the same as that found in traditional lasers. This manuscript presents a detailed study of the ablation characteristics of a nickel-titanium (NiTi) shape memory alloy in air with femtosecond laser pulses. The single- and multishot ablation threshold fluence and the incubation coefficient (predicting the extent to which accumulation could take place in a material) are evaluated. In addition, morphological changes, such as the emergence of a ripple pattern, are discussed along with the identification of gentle and strong ablation phases. This study provides for the understanding and characterization of NiTi micromachining using FLM technology, which could aid in the identification of new applications for smart materials in the macro-, nano-, and microelectromechanical system domains using this technology.

Thermomechanical and electrical response of a superelastic NiTi shape memory alloy cable

2020 ◽  
Vol 31 (19) ◽  
pp. 2229-2242 ◽  
Author(s):  
Muhammad M Sherif ◽  
Osman E Ozbulut
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Smart Materials ◽  
Complex Geometry ◽  
Electrical Response ◽  
High Energy ◽  
Temperature History ◽  
Niti Shape Memory Alloy ◽  
Outer Diameter ◽  
Resistance Change

Superelastic shape memory alloys are a unique class of smart materials that can recover up to 6% strains. Due to their appealing properties such as high energy dissipation and corrosion resistance, several researchers have assessed the use of such materials in numerous applications ranging from biomedical to civil engineering. This article investigates the thermomechanical and electrical response of a NiTi shape memory alloy cable with a complex configuration subjected to cyclic loading of various strain amplitudes ranging from 3% to 7%. The cable consists of several multi-layered strands with a cumulative outer diameter of 5.5 mm. The thermomechanical results indicate a good correlation of the change in cable temperature with the applied strains and maximum stresses. The temperature history can be used to map the degradation pattern of the shape memory alloy cable. In addition, due to the complex geometry of the cable, the global electrical resistance change does not predict the strain/stress state of the cable; however, it can be used to predict the onset of phase transformations.

Spool-packaging of shape memory alloy actuators: Performance model and experimental validation

2012 ◽  
Vol 23 (2) ◽  
pp. 201-219 ◽  
Author(s):  
John A Redmond ◽  
Diann Brei ◽  
Jonathan Luntz ◽  
Alan L Browne ◽  
Nancy L Johnson
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Smart Materials ◽  
Experimental Validation ◽  
Low Cost ◽  
Static Model ◽  
Performance Model ◽  
Sma Actuators ◽  
Analysis And Synthesis ◽  
High Yields

Shape memory alloy (SMA) actuators in the wire form are attractive because of their simplistic architecture and electrical operation, and their manufacturability at high yields and low cost. While SMA actuators are known for their superior work density among smart materials, packaging long lengths of SMA wire needed for moderate to large motions is an ongoing technical challenge. This article investigates spooling as a packaging approach to provide more compact actuator footprints. An analytical, quasi-static model is derived to provide a foundational tool for the analysis and synthesis of spool-packaged SMA wire actuators. The model predicts motion with respect to a generalized architecture, and specifiable geometric, material, and loading parameters. The model prediction accounts for the effects of local friction loss and bending strains, and for a “binding” limitation due to accumulated friction. An experimental validation study demonstrates the model’s ability to predict actuator motion well in terms of form and magnitude with respect to load and packaging geometry. This model provides a basis for a systematic application of spooled-packaging techniques to overcome packaging limitations of SMA, positioning SMA wire actuators as a viable alternative in many applications.

scholarly journals Polymer based microneedle patch fabricated using microinjection moulding

2018 ◽  
Vol 192 ◽  
pp. 01039 ◽  
Author(s):  
Pattanaphong Janphuang ◽  
Mongkhol Laebua ◽  
Chanwut Sriphung ◽  
Phatsakon Taweewat ◽  
Anan Sirichalarmkul ◽  
...  
Keyword(s):  
Injection Moulding ◽  
Production Efficiency ◽  
Electrical Discharge Machining ◽  
Low Cost ◽  
Injection Pressure ◽  
Mould Insert ◽  
Moulding Process ◽  
Injection Moulding Process ◽  
Microneedle Patch ◽  
Microinjection Moulding

This paper presents the development of a polymer based microneedle patch for transdermal drug delivery application using plastic microinjection moulding. Design and analysis of the microneedle cavities and mould insert used in the injection moulding process were carried out using Computer-Aided Engineering (CAE) software. A mould insert with low surface roughness was fabricated using Micro Electrical Discharge Machining (μ-EDM). The injection moulding parameters including clamping force, temperature, injection pressure and velocity were characterized in order to obtain the optimum reproducibility. Solid truncated cone microneedles, made of biocompatible polymethyl methacrylate (PMMA), with a round tip radius of 50 μm and 500 μm in height have been realized by microinjection moulding process demonstrating the potential of a low cost, high production efficiency, and suitable for mass production. In addition, a mould insert of cylindrical microneedles fabricated using X-ray LIGA has been proposed.

Development of a Shape Memory Alloy Heat Engine Through Experiment and Modeling

2011 ◽  
Author(s):  
Andrew C. Keefe ◽  
Geoffrey P. McKnight ◽  
Guillermo A. Herrera ◽  
P. Anthony Bedegi ◽  
Christopher B. Churchill ◽  
...  
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Energy Recovery ◽  
Waste Heat ◽  
Low Cost ◽  
Heat Engine ◽  
Niti Shape Memory Alloy ◽  
Material Development ◽  
Work Cycle ◽  
Forced Air

Few technologies can produce meaningful power from low temperature waste heat sources below 250°C, particularly on a per-mass basis. Since the 1970’s energy crisis, NiTi shape memory alloy (SMA) and associated thermal engines have been considered a viable heat-to-power transducer but were not adopted due to previously poor material quality, low supply, design complexity, and cost. Decades of subsequent material development, research, and commercialization have resulted in the availability of consistently high-quality, well-characterized, low cost alloys and a renewed interest in SMA as a waste heat energy recovery technology. The Lightweight Thermal Energy Recovery System (LighTERS) is an ongoing ARPA-E funded collaboration between General Motors Company, HRL Laboratories, Dynalloy, Inc., and the University of Michigan. In this paper we will present initial results from investigations of a closed loop SMA thermal engine (a refinement of the Dr. Johnson design) using a helical coil element and forced-air heat exchange. This engine generates mechanical power by continuously pulling itself through separate hot and cold air streams using the shape memory phase transformation to alternately expand and contract at frequencies between 0.25 and 2 Hz. This work cycle occurs continuously along the length of the coil loop and produces steady state power against an external moment. We present engine features and the thermal envelope that resulted in devices achieving between 0.1 and 0.5 W/g of shape memory alloy material using only forced air heat exchangers and room temperature cooling.

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