Multifunctional Composite Structures With Integrated Damping Treatments: A Parametric Study

A parametric study on composite laminate plates with integrated damping treatment is realized. The goal is to assess the impact of a viscoelastic core on the mechanical performances as well as on the vibration damping efficiency. This work considers as design parameters the damping layer thickness and its position in the laminate lay-up. The obtained results enable to propose a guideline for multifunctional composite structure with intergrated damping treatment.

The Study of a Control Signal’s Phase Shift Influence on the Efficiency of a System for Active Vibration Damping Based on MFC Piezoelectric Transducers

MATEC Web of Conferences ◽

10.1051/matecconf/202031801005 ◽

2020 ◽

Vol 318 ◽

pp. 01005

Author(s):

Marek Płaczek

Keyword(s):

Phase Shift ◽

Smart Materials ◽

Composite Structures ◽

Fiber Composite ◽

Vibration Damping ◽

Piezoelectric Transducers ◽

Piezoelectric Composite ◽

Active Vibration Damping ◽

Active Vibration ◽

Active vibration damping of mechanical systems based on applications of smart materials has a large application potential and is getting more and more popular. In active vibration systems the fast response of actuators to the signals generated by sensors is one of the most important element that decides of the system’s efficiency because the idea is to generate force by active elements that will suppress the vibrations detected by the sensors. In this paper results of laboratory tests of a control signal’s phase shift influence on the efficiency of a system for active vibration damping based on application of Macro Fiber Composite (MFC) piezoelectric transducers are presented. MFCs are modern piezoelectric composite transducers produced as a thin, elastic films and can be easily installed on the surface of the mechanical subsystem or laminated in composite structures. The impact of the phase shifting between signals generated to power the actuator on the damping efficiency was verified and analysed. It was verified in what phase angle the damping of vibration has the best efficiency and if the shift of the signals causes the linear loss of the system efficiency. It was also verified whether it causes the same effects in both directions of shifting (advance or delay in the phase of the signal supplying the damper relative to the signal generated by the beam’s vibration).

Bonding between high-performance polymer processed by Fused Filament Fabrication and PEEK/carbon fiber laminate

10.25518/esaform21.2335 ◽

2021 ◽

Author(s):

Isciane Caprais ◽

Pierre Joyot ◽

Emmanuel Duc ◽

Simon Deseur

Keyword(s):

Additive Manufacturing ◽

Composite Structures ◽

Composite Laminate ◽

High Performance ◽

Processing Conditions ◽

Fused Filament Fabrication ◽

Fiber Placement ◽

High Performance Polymer ◽

Automated Fiber Placement ◽

Automated fiber placement processes could be combined with additive manufacturing to produce more functionally complex composite structures with more flexibility. The challenge is to add functions or reinforcements to PEEK/carbon composite parts manufactured by automated fiber placement process, with additive manufacturing by fused filament fabrication. This consists of extruding a molten polymer through a nozzle to create a 3D part. Bonding between polymer filaments is a thermally driven phenomenon and determines the integrity and the final mechanical strength of the printed part. 3d-printing high performance polymers is still very challenging because they involve high thermal gradients during the process. The purpose of this work is to find a process window where the bonding strength is maximized between the composite laminate and the first layer of printed polymer, and inside the printed function as well. Experimental measurements of the temperature profiles at the interface between a composite substrate and 3d-printed PEI under different processing conditions were carried out. The interface was observed using microscopic sections. The methodology for studying the impact of printing parameters on the cohesion and adhesion of printed parts with a composite laminate is described. This work provides insights about the influence of processing conditions on the bond formation between high-performance polymer surfaces. It highlights the importance of controlling the thermal history of the materials all along the process.

Study of the Design Representation Methods for the Optimization of Multi-Layer Composite Structures

Volume 2B: 43rd Design Automation Conference ◽

10.1115/detc2017-67309 ◽

2017 ◽

Author(s):

Hongyi Xu ◽

Junqi Yang ◽

Ching-Hung Chuang ◽

Zhenfei Zhan

Keyword(s):

Composite Structure ◽

Composite Structures ◽

Structure Optimization ◽

Optimization Methods ◽

Optimization Strategy ◽

Root Cause ◽

Design Representation ◽

Layer Composite ◽

Low Efficiency ◽

The purpose of multi-layer composite structure optimization is to find the optimal composite layout, such that superior structure performances and lightweight can be achieved. However, the existing optimization methods have a low efficiency when applied to the multi-component, multi-layer composite structure. Such low efficiency is caused by the high dimensionality and the inherent shortcomings of the existing design representation methods. In this work, two composite layout representation methods are compared to better understand their impacts on optimization. The root cause of the low efficiency is identified, and its influences are also quantified using three metrics. Furthermore, a new Representation-Switch Optimization (RSO) strategy is proposed. This strategy improves the search efficiency by switching the design representation methods during the optimization process. Three benchmark studies, two mathematical examples and one real engineering example, are conducted to demonstrate the impact of design representation methods on the optimization results, as well as the effectiveness of the proposed optimization strategy.

Research on Dynamic Cumulative Damage Effect of Metal Rubber and Stress Wave Propagation Characteristics of Layered Composite Structure

Science of Advanced Materials ◽

10.1166/sam.2021.3997 ◽

2021 ◽

Vol 13 (5) ◽

pp. 981-990

Author(s):

Youchun Zou ◽

Chao Xiong ◽

Junhui Yin ◽

Kaibo Cui ◽

Huiyong Deng ◽

...

Keyword(s):

Stress Wave ◽

Composite Structure ◽

Composite Structures ◽

Impact Resistance ◽

Layered Composite ◽

Damage Effect ◽

Stress Wave Propagation ◽

Metal Rubber ◽

Layered Composite Structures ◽

The development of protective materials and structures is of great significance for improving the impact resistance, penetration resistance and spalling resistance of military equipment. At present, the layered composite structure has been widely used due to its good protective performance. In this paper, a special elastic porous material-metal rubber (MR) with excellent cushioning and damping properties was used to prepare high-performance layered composite structures. To begin with, the dynamic mechanical response and the dynamic cumulative damage effect of MR were studied through Split-Hopkinson Pressure Bar (SHPB) tests. Then, the failure form and stress wave propagation characteristics of the layered composite structures were investigated through SHPB tests and finite element method. The results show that repeated impacts can enhance the compactness of MR, thereby increasing the ultimate bearing capacity and energy absorption capacity, which is beneficial for MR to resist repeated impacts. The MR in composite structures can reduce ceramic damage, attenuate stress wave and smooth stress distribution. The titanium alloy on the back of the ceramic will aggravate the damage of the ceramic, and ultra-high molecular weight polyethylene on the back of the ceramic provides cushioning for the ceramic. Therefore, the impact resistance of the composite structure can be improved by adding MR and the reasonable arrangement of materials, and the SiC/UHMWPE/MR/TC4 composite structure has relatively reasonable stress distribution and better protection performance.

The Effect of Nano-Sized Air Bubbles on the Mechanical Properties and Natural Frequencies of a Multi-Cracked Composite Bar

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.30.65 ◽

2017 ◽

Vol 30 ◽

pp. 65-84 ◽

Author(s):

Ahmad Al-Maharma ◽

Naser Al-Huniti

Keyword(s):

Mechanical Properties ◽

Epoxy Resin ◽

Composite Structure ◽

Hybrid Composite ◽

Composite Structures ◽

Natural Frequencies ◽

Volume Fraction ◽

Multiple Cracks ◽

Air Bubbles ◽

In this research, the effect of nanosized air bubbles embedded within carbon nanotubes (CNTs) coated by various thicknesses of alumina (Al2O3) reinforced epoxy resin based composite on the natural frequencies of a multi-cracked bar is investigated in details. The impact of cracks’ locations and depths within the hybrid composite structure on the natural frequency profiles is investigated. The volume fraction of CNTs is fixed to 0.5 wt. % due to the significant improvements reported in the literature when the composite is reinforced with this volume fraction of CNTs. The results of the multi-scale finite element analysis are verified by comparing with previous studies and a good agreement is shown relating to the longitudinal natural frequencies. The results of the research show that the dynamic response of cracked bar is highly sensitive to the volume fractions of nanosized air bubbles located within the composite. The results of the study supported the hypothesis that the nanosized air bubbles can be used to reduce the weight of heavy composite structures along with using of suitable coatings to improve the mechanical properties of the hybrid composite. Furthermore. The results of the study can be employed to detect multiple cracks located within similar structures like wind turbine blade (WTB) fabricated from a hybrid composite structure composed of carbon fiber reinforced modified epoxy resin which contains nanosized air bubbles and CNTs nanofillers coated by Al2O3 at different thicknesses.

Seismic Behavior of Steel-Concrete Composite Structures

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.b5134.129219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 4721-4726

Keyword(s):

Composite Structure ◽

Composite Structures ◽

Seismic Behavior ◽

Shear Connector ◽

The Impact ◽

Direct Investigation ◽

Numerical Examination

Steel-Concrete composite individuals are an intriguing alternative for auxiliary originators, yet the dependability of plan strategies both on account of gravity and seismic burdens is in persistent advancement. Composite steelconcrete design gives a noteworthy economy through decreased materials and quicker development, such framework utilizes each kind of part in the most proficient way to expand the basic and financial advantages. In this undertaking, hypothetical, numerical perspectives and applications concerning the seismic conduct of steel-concrete composite structures are to be dissected. The intrigue has been concentrating around there on the capacity of composite encircled structures to disseminate seismic vitality by methods for inelastic disfigurements with the goals to: (1) Apply non-direct investigation strategies to assess building execution. (2) The chief highlights influencing the seismic reaction of composite edges. (3) A numerical examination has been direct to research the impact of composite conduct of the structures. (4) A limited component modular has been create to represent the dynamic conduct of composite structure and (5) The impact of shear connector on the conduct of composite encircled structure in seismic stacking

Impact Resistance of Filament Wound Composite Pipes: A Parametric Study

Volume 3: Design and Analysis ◽

10.1115/pvp2014-28941 ◽

2014 ◽

Author(s):

Abul Fazal M. Arif ◽

M. Haris Malik ◽

A. S. Al-Omari

Keyword(s):

Parametric Study ◽

Low Velocity Impact ◽

Design Parameters ◽

Low Velocity ◽

Velocity Impact ◽

Filament Wound ◽

Filament Wound Composite ◽

Composite Pipes ◽

The Impact ◽

Wound Composite

Filament wound composite pipes are being used in more and more applications. However, the impact behavior of these pipes is of particular importance in many applications. The sudden failure of these pipes under low velocity impact loads can be dangerous especially when the medium inside the pipe is hazardous or toxic in nature. The impact response of a composite laminate depends upon various factors such as thickness, stacking sequence and number of layers. The primary focus of this paper is parametric study of low velocity impact damage of CFRP and GFRP pipes under varying design parameters using finite element analysis. The simulation results are then used along with the ANN (Artificial Neural Networks) to fit a function to estimate the amount of absorbed energy.

FIRE RESISTACE OF SHEAR CONNECTORS FOR COMPOSITE BEAMS

Building and reconstruction ◽

10.33979/2073-7416-2020-92-6-59-65 ◽

2020 ◽

Vol 92 (6) ◽

pp. 59-65

Author(s):

G.P. TONKIH ◽

◽

D.A. CHESNOKOV ◽

◽

Keyword(s):

Fire Resistance ◽

Composite Structure ◽

Composite Structures ◽

Composite Beams ◽

Design Codes ◽

Connection Strength ◽

Shear Connectors ◽

Shear Connection ◽

Capacity Reduction ◽

Russian Research

Most of Russian research about composite structure fire resistance are dedicated to the composite slab behavior. The composite beams fire resistance had been never investigated in enough volume: the temperature evaluation within the scope of the actual Russian design codes leads to the significant reduction in the shear connection strength. Meanwhile, there no correlation between the strength decreasing and type of the shear connection. The article provides an overview of the relevant researches and offers some approaches which could take into account bearing capacity reduction of the shear connectors within composite structures design.

Volume 1: Advanced Packaging; Emerging Technologies; Modeling and Simulation; Multi-Physics Based Reliability; MEMS and NEMS; Materials and Processes ◽

A Fracture Mechanics Based Parametric Study of the Copper-to-Copper Direct Thermo-Compression Bonded Interface Using Finite Element Method

10.1115/ipack2013-73280 ◽

2013 ◽

Author(s):

Ah-Young Park ◽

Satish Chaparala ◽

Seungbae Park

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Parametric Study ◽

Initial Crack ◽

Bonding Interface ◽

Interface Condition ◽

Large Temperature ◽

Bonded Interface ◽

The Impact ◽

Element Method

Through-silicon via (TSV) technology is expected to overcome the limitations of I/O density and helps in enhancing system performance of conventional flip chip packages. One of the challenges for producing reliable TSV packages is the stacking and joining of thin wafers or dies. In the case of the conventional solder interconnections, many reliability issues arise at the interface between solder and copper bump. As an alternative solution, Cu-Cu direct thermo-compression bonding (CuDB) is a possible option to enable three-dimension (3D) package integration. CuDB has several advantages over the solder based micro bump joining, such as reduction in soldering process steps, enabling higher interconnect density, enhanced thermal conductivity and decreased concerns about intermetallic compounds (IMC) formation. Critical issue of CuDB is bonding interface condition. After the bonding process, Cu-Cu direct bonding interface is obtained. However, several researchers have reported small voids at the bonded interface. These defects can act as an initial crack which may lead to eventual fracture of the interface. The fracture could happen due to the thermal expansion coefficient (CTE) mismatch between the substrate and the chip during the postbonding process, board level reflow or thermal cycling with large temperature changes. In this study, a quantitative assessment of the energy release rate has been made at the CuDB interface during temperature change finite element method (FEM). A parametric study is conducted to analyze the impact of the initial crack location and the material properties of surrounding materials. Finally, design recommendations are provided to minimize the probability of interfacial delamination in CuDB.

Coir Fibers Treated with Henna as a Potential Reinforcing Filler in the Synthesis of Polyurethane Composites

Materials ◽

10.3390/ma14051128 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1128

Author(s):

Sylwia Członka ◽

Anna Strąkowska ◽

Agnė Kairytė

Keyword(s):

Mechanical Properties ◽

High Energy ◽

Dynamic Mechanical Properties ◽

Milling Process ◽

Coir Fiber ◽

Lawsonia Inermis ◽

Coir Fibers ◽

Mechanical Performances ◽

The Impact ◽

Reinforcing Filler

In this study, coir fibers were successfully modified with henna (derived from the Lawsonia inermis plant) using a high-energy ball-milling process. In the next step, such developed filler was used as a reinforcing filler in the production of rigid polyurethane (PUR) foams. The impact of 1, 2, and 5 wt % of coir-fiber filler on structural and physico-mechanical properties was evaluated. Among all modified series of PUR composites, the greatest improvement in physico-mechanical performances was observed for PUR composites reinforced with 1 wt % of the coir-fiber filler. For example, on the addition of 1 wt % of coir-fiber filler, the compression strength was improved by 23%, while the flexural strength increased by 9%. Similar dependence was observed in the case of dynamic-mechanical properties—on the addition of 1 wt % of the filler, the value of glass transition temperature increased from 149 °C to 178 °C, while the value of storage modulus increased by ~80%. It was found that PUR composites reinforced with coir-fiber filler were characterized by better mechanical performances after the UV-aging.