Exploitation of composite materials as vibration isolator and damper in machine tools and other mechanical systems: A review

Large-scale mechanical systems for impregnating and positioning composite materials are now permitting efficient manufacturing of composite hulls up to 60 m (200 ft) and greater. Recreational, commercial, and military vessels fabricated from composite materials are gaining acceptance around the world; however, processing of thermosetting resins and fiber reinforcements in quantities exceeding 90 000 kg (200 000 lb) per unit presents a new set of challenges to production engineers responsible for maintaining quality control. Impregnation systems are currently being used at several mine-hunter production shipyards worldwide. Large-to-medium sized recreational yachts are also in production with impregnation systems. This paper reviews some past and current impregnator installations, the selection process used for choosing the systems, and production engineering factors.

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Mechanical and dynamic properties of alternate materials for machine tool structures: A review

Journal of Reinforced Plastics and Composites ◽

10.1177/0731684418799946 ◽

2018 ◽

Vol 37 (24) ◽

pp. 1456-1467 ◽

Cited By ~ 8

Author(s):

S Murugan ◽

PR Thyla

Keyword(s):

Composite Materials ◽

Machine Tool ◽

Dynamic Characteristics ◽

Machine Tools ◽

Large Scale ◽

Dynamic Properties ◽

Research Work ◽

Present Review ◽

High Speeds ◽

Machine Tool Structures

Machine tool structures find large-scale applications in various machining industries due to their necessity to design several kinds of machines. However, the vibration produced on machining is a significant problem which has to be overcome. To suppress the vibration, several researchers have attempted to enhance the machine tool structure’s dynamic characteristics in the recent past. The composite materials have risen up as a new kind of material for the manufacture of machine tool structures with producing lesser vibrations since the past few decades. To increase the production of precision products, machining should be done at high speeds without producing vibration. The dynamic characteristics such as natural frequency as well as damping of machine tool structures are very important parameters. Hence, the improvement of these parameters is nothing but the improvement of dynamic characteristics, as said earlier. Therefore, the present review elaborates various available reports on the improved dynamic characteristics of machine tools. The review focused mainly on mechanical and dynamic properties of alternate materials for machine tools with different composite materials. Furthermore, conflicting conditions of suitable alternate material for the preparation of machine tools are also focused in the present review. To the best of our knowledge, the review on the use of alternate materials for the manufacturing of machine tool structures has not been reported elsewhere and hence the present review will provide useful information for subsequent researchers to enhance the scope of research work in the area of manufacturing machine tool structures.

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A Variational Formulation for the Dynamic Hygrothermoelastic Finite Element Analysis of Mechanical Systems Fabricated With Polymeric Composite Materials

13th Design Automation Conference: Volume 1 — Design Methods, Computer Graphics, and Expert Systems ◽

10.1115/detc1987-0029 ◽

1987 ◽

Author(s):

C. K. Sung ◽

B. S. Thompson ◽

M. V. Gandi

Keyword(s):

Finite Element ◽

Composite Materials ◽

Elevated Temperatures ◽

Mechanical Systems ◽

Polymeric Composite ◽

Polymeric Materials ◽

High Strength ◽

Superior Performance ◽

Element Formulation ◽

High Stiffness

Abstract Many classes of mechanical systems must now be designed with members possessing high stiffness-to-weight ratios and high strength-to-weight ratios in order to achieve superior performance characteristics. One of the philosophies proposed for addressing these classes of problems requires the articulating members to be fabricated with modern composite materials. While these materials enable high-strength, high-stiffness and low-mass members to be fabricated, the properties of these polymeric materials are adversely affected by elevated temperatures and also moisture absorption. The subject of this paper is the development of a methodology for predicting the dynamic hygrothermoelastic response of machine systems fabricated with these advanced materials. This methodology is based on a variational theorem which provides the basis for a finite element formulation. An illustrative example serves to demonstrate some preliminary work on predicting the response of a four-bar linkage fabricated with polymeric composite links simultaneously subjected to both mechanical and hygrothermal loadings.

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Comparative Microstructures of Ion Milled and Electrochemically Thinned Composite Materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052742 ◽

1974 ◽

Vol 32 ◽

pp. 546-547

Author(s):

R.R. Russell

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Composite Materials ◽

Great Difficulty ◽

Ion Milling ◽

Transmission Electron ◽

Ion Damage ◽

Intermetallic Composite

Transmission electron microscopy of metallic/intermetallic composite materials is most challenging since the microscopist typically has great difficulty preparing specimens with uniform electron thin areas in adjacent phases. The application of ion milling for thinning foils from such materials has been quite effective. Although composite specimens prepared by ion milling have yielded much microstructural information, this technique has some inherent drawbacks such as the possible generation of ion damage near sample surfaces.

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The Chatterbox: A Device for Hearing Chatter as Sections are Cut

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072241 ◽

1973 ◽

Vol 31 ◽

pp. 360-361

Author(s):

C. W. McCutchen ◽

Lois W. Tice

Keyword(s):

Machine Tools ◽

Cutting Tool ◽

Guerilla Warfare ◽

History Of ◽

Chatter Marks

Ultramicrotomists live in a state of guerilla warfare with chatter. This situation is likely to be permanent. We can infer this from the history of machine tools. If set the wrong way for the particular combination of cutting tool and material, most if not all machine tools will chatter.In more than 100 years since machine tools became common, no one has evolved a practical recipe that guarantees avoiding chatter. Rather than follow some single very conservative rule to avoid chatter in all cases, machinists detect it when it happens, and change conditions until it stops. This is possible because they have no trouble telling when their cutting tool is chattering. They can see chatter marks, and they can also hear a sometimes deafening noise.

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Transmission electron microscopy of composite materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100107125 ◽

1988 ◽

Vol 46 ◽

pp. 1012-1015

Author(s):

K.P.D. Lagerlof

Keyword(s):

Composite Materials ◽

Physical Properties ◽

Structural Defects ◽

Structural Composites ◽

Multiphase Materials ◽

Structural Reinforcement ◽

Transmission Electron ◽

Reinforced Fiber ◽

Particulate Reinforced Composites ◽

Definition Of

Although most materials contain more than one phase, and thus are multiphase materials, the definition of composite materials is commonly used to describe those materials containing more than one phase deliberately added to obtain certain desired physical properties. Composite materials are often classified according to their application, i.e. structural composites and electronic composites, but may also be classified according to the type of compounds making up the composite, i.e. metal/ceramic, ceramic/ceramie and metal/semiconductor composites. For structural composites it is also common to refer to the type of structural reinforcement; whisker-reinforced, fiber-reinforced, or particulate reinforced composites [1-4].For all types of composite materials, it is of fundamental importance to understand the relationship between the microstructure and the observed physical properties, and it is therefore vital to properly characterize the microstructure. The interfaces separating the different phases comprising the composite are of particular interest to understand. In structural composites the interface is often the weakest part, where fracture will nucleate, and in electronic composites structural defects at or near the interface will affect the critical electronic properties.

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Vibration Isolator System for Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017966x ◽

1990 ◽

Vol 48 (1) ◽

pp. 182-183

Author(s):

K. Ohi ◽

M. Mizuno ◽

T. Kasai ◽

Y. Ohkura ◽

K. Mizuno ◽

...

Keyword(s):

Electron Microscope ◽

Magnetic Fields ◽

Environmental Conditions ◽

Vibration Isolator ◽

Air Conditioners ◽

Vibration Isolators ◽

Large Size ◽

Electron Microscopes

In recent years, with electron microscopes coming into wider use, their installation environments do not necessarily give their performance full play. Their environmental conditions include air-conditioners, magnetic fields, and vibrations. We report a jointly developed entirely new vibration isolator which is effective against the vibrations transmitted from the floor.Conventionally, large-sized vibration isolators which need the digging of a pit have been used. These vibration isolators, however, are large present problems of installation and maintenance because of their large-size.Thus, we intended to make a vibration isolator which1) eliminates the need for changing the installation room2) eliminates the need of maintenance and3) are compact in size and easily installable.

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