Theory of Time-Dependent Rupture and Interpretation of Some Stress-Rupture Data

Author(s):  
D. N. Frey
Author(s):  
Lewis R. Swank

Today there is a rapidly growing interest in the use of ceramics for structural applications. In applying structural ceramics it is necessary to estimate the time dependent failure behavior of the material. An analytical method is required to utilize flexural fast fracture and stress rupture data to predict the time dependent behavior of complex structures. This paper proposes an empirical equation to correlate the data. The proposed equation is applied to flexural and spin disk data. The flexural data correlate reasonably well. The spin disk data correlate well if the assumption is made that the stress in the flexural stress rupture specimens of the data base are those of steady state creep.


2006 ◽  
Vol 519-521 ◽  
pp. 1041-1046 ◽  
Author(s):  
Brian Wilshire ◽  
H. Burt ◽  
N.P. Lavery

The standard power law approaches widely used to describe creep and creep fracture behavior have not led to theories capable of predicting long-term data. Similarly, traditional parametric methods for property rationalization also have limited predictive capabilities. In contrast, quantifying the shapes of short-term creep curves using the q methodology introduces several physically-meaningful procedures for creep data rationalization and prediction, which allow straightforward estimation of the 100,000 hour stress rupture values for the aluminum alloy, 2124.


Author(s):  
Kyungmok Kim

In this article, a creep–rupture model of aluminum alloys is developed using a time-dependent cohesive zone law. For long-term creep rupture, a time jump strategy is used in a cohesive zone law. Stress–rupture scatter of aluminum alloy 4032-T6 is fitted with a power law form. Then, change in the slope of a stress-rupture line is identified on a log–log scale. Implicit finite element analysis is employed with a model containing a cohesive zone. Stress–rupture curves at various given temperatures are calculated and compared with experimental ones. Results show that a proposed method allows predicting creep–rupture life of aluminum alloys.


2016 ◽  
Vol 51 (14) ◽  
pp. 6639-6661 ◽  
Author(s):  
Amy Engelbrecht-Wiggans ◽  
Stuart Leigh Phoenix

Author(s):  
Jie Zhao ◽  
Dong-ming Li ◽  
Yuan-yuan Fang ◽  
Shi-jie Zhu

It has been noted that the use of safety coefficient can deal with uncertainties existed in practical structures, while reliability concept provides more precise results by considering the real distribution of creep rupture property. Generally, creep rupture data of a heat-resistant steel can be compressed into a narrow band by using a temperature-time parametric method such as Larson-Miller or Manson-Haferd method. In order to describe the scattering of the data, the current paper proposes a “Z parameter” method to represent the magnitude of the deviation of the rupture data to master curve. Statistical analysis shows that the scattering of Z parameter for several types of steels is supported by normal distribution. Using this method, it is possible to achieve unified analysis of the creep rupture data in various temperature and stress conditions. Stress-TTP-Reliability curves (σ-TTP-R curves), Stress-Rupture time-Reliability curves (σ-tr-R curves) and Allowable stress-Temperature-Reliability curves ([σ]-T-R curves) are proposed which could embrace reliability concept into creep rupture property design.


1983 ◽  
Vol 105 (2) ◽  
pp. 93-98 ◽  
Author(s):  
G. H. Rowe

Experimental results for eight linearly increasing stress-to rupture tests at 649°C, 732°C, and 816°C agree with analytical rupture time predictions using the Larson-Miller time-temperature parameter stress-rupture curve for the temperature range, 649°C to 899°C. An anomaly in 649°C stress-rupture behavior is disclosed, whereby the increasing stress-to-rupture time predictions at 649°C do not agree with the stress-rupture curve constructed from the actual 649°C stress-rupture data.


Sign in / Sign up

Export Citation Format

Share Document