Characterization of the Mechanical Properties of Sensitive Clay by Means of Indentation Tests

The paper reports the results of an extensive characterization of the Ti6Al4V-SiCfcomposite produced by hot isostatic pressing (HIP) to assess its capability to withstand the in-service conditions of turbine blades operating at middle temperatures in aeronautical engines. The microstructure of composite, in as-fabricated condition and after long-term heat treatments (up to 1,000 hours) in the temperature range 673-873 K, has been investigated by means of different techniques. Particular attention was paid to the micro-chemical evolution of fibre-matrix interface which is scarcely affected also by the most severe heat treatments examined here. This leads to stable mechanical properties as evidenced by hardness, tensile and FIMEC instrumented indentation tests. Therefore, the composite can operate at the maximum temperature (873 K) foreseen for its aeronautical applications without remarkable modifications of its microstructure and degradation of mechanical properties. The mechanical characterization has been completed by internal friction and dynamic modulus measurements carried out both at constant and increasing temperature, from 80 to 1173 K.

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Inverse Characterization of Nonlinear Anisotropic Mechanical Properties of Engineered Cardiovascular Tissues Using a Spherical Indentation Test

ASME 2007 Summer Bioengineering Conference ◽

10.1115/sbc2007-175762 ◽

2007 ◽

Author(s):

M. A. J. Cox ◽

R. A. Boerboom ◽

C. V. C. Bouten ◽

N. J. B. Driessen ◽

F. P. T. Baaijens

Keyword(s):

Mechanical Properties ◽

Soft Tissues ◽

Indentation Test ◽

Tensile Tests ◽

Material Behavior ◽

Uniaxial Tensile ◽

Spherical Indentation ◽

Mechanical Conditioning ◽

Indentation Tests

Over the last few years, research interest in tissue engineering as an alternative for e.g. current treatment and replacement strategies for cardiovascular and heart valve diseaes has significantly increased. In vitro mechanical conditioning is an essential tool for engineering strong implantable tissues [1]. Detailed knowledge of the mechanical properties of the native tissue as well as the properties of the developing engineered constructs is vital for a better understanding and control of the mechanical conditioning process. The typical highly nonlinear and anisotropic behavior of soft tissues puts high demands on their mechanical characterization. Current standards in mechanical testing of soft tissues include (multiaxial) tensile testing and indentation tests. Uniaxial tensile tests do not provide sufficient information for characterizing the full anisotropic material behavior, while biaxial tensile tests are difficult to perform, and boundary effects limit the test region to a small central portion of the tissue. In addition, characterization of the local tissue properties from a tensile test is non-trivial. Indentation tests may be used to overcome some of these limitations. Indentation tests are easy to perform and when indenter size is small relative to the tissue dimensions, local characterization is possible. Therefore, we propose a spherical indentation test using finite deformations.

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Microstructural and fractographic characterization of B4C-Al cermets tested under dynamic and static loading

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154780 ◽

1989 ◽

Vol 47 ◽

pp. 562-563

Author(s):

Gyeung Ho Kim ◽

Mehmet Sarikaya ◽

D. L. Milius ◽

I. A. Aksay

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Fracture Toughness ◽

Static Loading ◽

Carbon Deposition ◽

Full Density ◽

Unique Combination ◽

Strong Component ◽

Reaction Products

Cermets are designed to optimize the mechanical properties of ceramics (hard and strong component) and metals (ductile and tough component) into one system. However, the processing of such systems is a problem in obtaining fully dense composite without deleterious reaction products. In the lightweight (2.65 g/cc) B4C-Al cermet, many of the processing problems have been circumvented. It is now possible to process fully dense B4C-Al cermet with tailored microstructures and achieve unique combination of mechanical properties (fracture strength of over 600 MPa and fracture toughness of 12 MPa-m1/2). In this paper, microstructure and fractography of B4C-Al cermets, tested under dynamic and static loading conditions, are described.The cermet is prepared by infiltration of Al at 1150°C into partially sintered B4C compact under vacuum to full density. Fracture surface replicas were prepared by using cellulose acetate and thin-film carbon deposition. Samples were observed with a Philips 3000 at 100 kV.

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Characterization of interfaces in CVD-coated nicalon fiber-reinforced SiC

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154755 ◽

1989 ◽

Vol 47 ◽

pp. 556-557

Author(s):

K.L. More ◽

R.A. Lowden

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Chemical Vapor ◽

Chemical Vapor Infiltration ◽

Frictional Stress ◽

Fiber Reinforced ◽

Pull Out ◽

Carbon Coated ◽

Fiber Matrix

The mechanical properties of fiber-reinforced composites are directly related to the nature of the fiber-matrix bond. Fracture toughness is improved when debonding, crack deflection, and fiber pull-out occur which in turn depend on a weak interfacial bond. The interfacial characteristics of fiber-reinforced ceramics can be altered by applying thin coatings to the fibers prior to composite fabrication. In a previous study, Lowden and co-workers coated Nicalon fibers (Nippon Carbon Company) with silicon and carbon prior to chemical vapor infiltration with SiC and determined the influence of interfacial frictional stress on fracture phenomena. They found that the silicon-coated Nicalon fiber-reinforced SiC had low flexure strengths and brittle fracture whereas the composites containing carbon coated fibers exhibited improved strength and fracture toughness. In this study, coatings of boron or BN were applied to Nicalon fibers via chemical vapor deposition (CVD) and the fibers were subsequently incorporated in a SiC matrix. The fiber-matrix interfaces were characterized using transmission and scanning electron microscopy (TEM and SEM). Mechanical properties were determined and compared to those obtained for uncoated Nicalon fiber-reinforced SiC.

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Characterization of Structure-Thermo-Mechanical Properties of Ultra High Temperature Ceramic Composites (UHTCCS) By Nondestructive Testing (NDT)

i-manager’s Journal on Mechanical Engineering ◽

10.26634/jme.3.3.2368 ◽

2013 ◽

Vol 3 (3) ◽

pp. 23-30

Author(s):

Manab Mallik ◽

◽

K.K. Roy ◽

Rahul Mitra ◽

Animesh Talapatra ◽

...

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Nondestructive Testing ◽

Ceramic Composites ◽

Ultra High Temperature

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PREPARATION AND CHARACTERIZATION OF REPROCESSED COMPOSITES OF POLYPROPYLENE REINFORCED BY WOOD FIBERS: PHYSICAL AND MECHANICAL PROPERTIES

10.26678/abcm.cobem2017.cob17-1636 ◽

2017 ◽

Author(s):

Thais Helena Sydenstricker Flores-Sahagun ◽

Kelly Priscila Agapito ◽

ROSA MARIA JIMENEZ AMEZCUA ◽

Felipe Jedyn

Keyword(s):

Mechanical Properties ◽

Physical And Mechanical Properties ◽

Wood Fibers

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Emerging Techniques for the Characterization of Nano-Mechanical Properties of Integrated Circuit Components

ISTFA 2008: Conference Proceedings from the 34th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2008p0121 ◽

2008 ◽

Author(s):

Nicholas Randall ◽

Rahul Premachandran Nair

Keyword(s):

Mechanical Properties ◽

Quality Control ◽

Integrated Circuits ◽

Integrated Circuit ◽

Manufacturing Process ◽

Solder Bumps ◽

Initial Work ◽

Circuit Components ◽

Materials Used

Abstract With the growing complexity of integrated circuits (IC) comes the issue of quality control during the manufacturing process. In order to avoid late realization of design flaws which could be very expensive, the characterization of the mechanical properties of the IC components needs to be carried out in a more efficient and standardized manner. The effects of changes in the manufacturing process and materials used on the functioning and reliability of the final device also need to be addressed. Initial work on accurately determining several key mechanical properties of bonding pads, solder bumps and coatings using a combination of different methods and equipment has been summarized.

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