|
|
|
Foundation ::
Failure Analysis ::
CARES_PC
|
CARES_PC
Ceramics Analysis and Reliability Evaluation of Structures- PC version
|
 |
Moderators:
Adopt This Application!
|
SOURCE CODE AVAILABLE
|
|
The beneficial properties of structural ceramics include their hightemperature strength, light weight, hardness, and corrosion and oxidation resistance. For advanced heat engines, ceramics have demonstrated functional abilities at temperatures well beyond the operational limits of metals. This is offset by the fact that ceramic materials tend to be brittle. When a load is applied, their lack of significant plastic deformation causes the material to crack at microscopic flaws, destroying the component.
CARES/PC performs statistical analysis of data obtained from the fracture of simple, uniaxial tensile or flexural specimens and estimates the Weibull and Batdorf material parameters from this data. CARES/PC is a subset of the program CARES which calculates the fast-fracture reliability or failure probability of ceramic components utilizing the Batdorf and Weibull models to describe the effects of multi-axial stress states on material strength. CARES additionally requires that the ceramic structure be modeled by a finite element program such as MSC/NASTRAN or ANSYS. The more limited CARES/PC does not perform fast-fracture reliability estimation of components.
CARES/PC estimates ceramic material properties from uniaxial tensile or from three- and four-point bend bar data. In general, the parameters are obtained from the fracture stresses of many specimens (30 or more are recommended) whose geometry and loading configurations are held constant. Parameter estimation can be performed for single or multiple failure modes by using the least-squares analysis or the maximum likelihood method. Kolmogorov-Smirnov and Anderson-Darling goodness-of-fit tests measure the accuracy of the hypothesis that the fracture data comes from a population with a distribution specified by the estimated Weibull parameters. Ninety-percent confidence intervals on the Weibull parameters and the unbiased value of the shape parameter for complete samples are provided when the maximum likelihood technique is used.
CARES/PC carries the NASA case number LEW-15248. It was originally released as part of the NASA COSMIC collection.
|
|
More software from National Technology Transfer Center
|
|
|
|
|
|
|
Open Channel Software runs entirely on Open Source Software. We return
value to the Software community in the form of
services and original software. Most of our
content is currently available as source code, with the
copyright owned by the original author, All
Rights Reserved. Everything else is Copyright
©2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Open Channel Software.
View our privacy statement.
Contact webmaster at openchannelsoftware dot org with questions.
|
|
|
