Computerized Evaluations of the Relative Abilities of Seven Time-Temperature Parameters to Correlate and Extrapolate Nickel Alloy Stress-Rupture Data

1972 ◽  
Vol 94 (1) ◽  
pp. 7-12 ◽  
Author(s):  
P. K. Raut ◽  
W. R. Clough
Keyword(s):  
Stress Rupture ◽  
Computer Programs ◽  
Graphical Methods ◽  
Data Sets ◽  
Test Results ◽  
Master Curves ◽  
Third Order ◽  
Rupture Data ◽  
Order Polynomial ◽  
Nickel Base

A total of 31 stress-rupture data sets for 28 different nickel-base alloys, including 1153 individual test results, have been treated by graphical methods and computer programs to allow determinations of the relative abilities of Larson-Miller, Manson-Haferd, Sherby-Dorn, Goldhoff-Sherby, Manson-Succop, Conrad and Korchynsky parameters to correlate and extrapolate data. For the correlation of all data the Goldhoff-Sherby and Manson-Haferd methods are attractive, while for extrapolation to longer times some superiority of the Manson-Haferd and Manson-Succop parameters is demonstrated. Overall use of a third order polynomial approximation to Manson-Haferd master curves is recommended, as is the avoidance of external extrapolation. Results are primarily based on modified and original computer programs and standard statistical treatments of data.

Computerized Time-Temperature Parametric Analysis of C, Mo, and Cr-Mo Steel Stress-Rupture Data

1973 ◽  
Vol 95 (1) ◽  
pp. 191-197
Author(s):  
P. K. Raut ◽  
W. R. Clough
Keyword(s):  
Parametric Analysis ◽  
Stress Rupture ◽  
Computer Programs ◽  
Data Sets ◽  
Master Curves ◽  
Statistical Measures ◽  
Rupture Data

Demonstrated by results obtained with highly modified or original computer programs, accomplished with 31 data sets for C, Mo, and Cr-Mo steels, is the general superiority of the new Goldhoff-Sherby and the older Manson-Haferd parameters for the correlation of stress-rupture data, as compared with the use of the Larson-Miller, Sherby-Dorn, Manson-Succop, Conrad, and Korchynsky methods. Abilities to correlate are based on values of statistical measures of scatter about master curves. Rupture-times in excess of 10,000 hr were used in separate computer runs to test the abilities of the seven parameters to extrapolate to longer times. For extrapolation the Goldhoff-Sherby and Manson-Haferd parameters are generally superior, but particular attention must be paid to the order of the polynomial used to approximate master curves.

Calibration of pneumotachographs using a calibrated syringe

2003 ◽  
Vol 95 (2) ◽  
pp. 571-576 ◽  
Author(s):  
Yongquan Tang ◽  
Martin J. Turner ◽  
Johnny S. Yem ◽  
A. Barry Baker
Keyword(s):  
Calibration Method ◽  
Linear Range ◽  
Data Sets ◽  
Constant Flow ◽  
Calibration Constant ◽  
Third Order ◽  
Polynomial Coefficients ◽  
Calibration Curves ◽  
Order Polynomial ◽  
Better Than

Pneumotachograph require frequent calibration. Constant-flow methods allow polynomial calibration curves to be derived but are time consuming. The iterative syringe stroke technique is moderately efficient but results in discontinuous conductance arrays. This study investigated the derivation of first-, second-, and third-order polynomial calibration curves from 6 to 50 strokes of a calibration syringe. We used multiple linear regression to derive first-, second-, and third-order polynomial coefficients from two sets of 6–50 syringe strokes. In part A, peak flows did not exceed the specified linear range of the pneumotachograph, whereas flows in part B peaked at 160% of the maximum linear range. Conductance arrays were derived from the same data sets by using a published algorithm. Volume errors of the calibration strokes and of separate sets of 70 validation strokes ( part A) and 140 validation strokes ( part B) were calculated by using the polynomials and conductance arrays. Second- and third-order polynomials derived from 10 calibration strokes achieved volume variability equal to or better than conductance arrays derived from 50 strokes. We found that evaluation of conductance arrays using the calibration syringe strokes yields falsely low volume variances. We conclude that accurate polynomial curves can be derived from as few as 10 syringe strokes, and the new polynomial calibration method is substantially more time efficient than previously published conductance methods.

Development of a Material Databook for API Std 530

2014 ◽  
Author(s):  
M. Prager ◽  
D. A. Osage ◽  
C. H. Panzarella ◽  
R. G. Brown
Keyword(s):  
Stress Rupture ◽  
American Petroleum Institute ◽  
Material Strength ◽  
Data Sets ◽  
Test Results ◽  
Stress Rupture Properties ◽  
Back Ground ◽  
Effects Of Temperature ◽  
Petroleum Refineries ◽  
Rupture Properties

In 2005, the American Petroleum Institute (API) initiated an effort to update existing yield, tensile and stress-rupture properties found in API Standard 530 Calculation of Heater Tube Thickness in Petroleum Refineries and add properties for alloys not yet covered. The design curves in API 530 until that time were based on data gathered 40 to 50 years earlier by the Materials Properties Council (MPC) and its predecessor, the ASTM-ASME Joint Committee on the Effects of Temperature on Materials. Later, MPC developed proprietary statistically sound algorithms to apply lot-centered regression for parametric analysis of large, unbalanced data sets of diverse heats tested under a variety of conditions. Subsequently, MPC built and maintained archives on the creep and stress-rupture data of alloys of interest to API. For some alloys the data sets contained over a thousand test results on over 100 heats. To assure that future designs will reflect the properties of materials produced using modern practices, API requested MPC to deliver design properties applicable to current materials. This paper presents the back ground, principles and results of the recent analyses performed by MPC that are now available for use by the API membership. The properties furnished in equation format are yield and ultimate tensile strengths for time-independent stresses and results of lot centered Larson-Miller Parameter analyses to obtain time-dependent average and minimum strengths. The properties and application examples of the equations are published as WRC Bulletin 541 Evaluation of Material Strength Data for Use in API Std 530.

Morphology, Distribution and Identification of Micro-Constituents Along Grain Boundaries in Nickel-Base Alloys

1973 ◽  
Vol 31 ◽  
pp. 176-177
Author(s):  
D. E. Fornwalt ◽  
A. R. Geary ◽  
B. H. Kear
Keyword(s):  
Electron Microscope ◽  
Grain Boundaries ◽  
Volume Fraction ◽  
Rupture Life ◽  
Stress Rupture ◽  
High Volume ◽  
Precipitate Morphology ◽  
Stress Rupture Life ◽  
Nickel Base ◽  
Scanning Electron

A systematic study has been made of the effects of various heat treatments on the microstructures of several experimental high volume fraction γ’ precipitation hardened nickel-base alloys, after doping with ∼2 w/o Hf so as to improve the stress rupture life and ductility. The most significant microstructural chan§e brought about by prolonged aging at temperatures in the range 1600°-1900°F was the decoration of grain boundaries with precipitate particles.Precipitation along the grain boundaries was first detected by optical microscopy, but it was necessary to use the scanning electron microscope to reveal the details of the precipitate morphology. Figure 1(a) shows the grain boundary precipitates in relief, after partial dissolution of the surrounding γ + γ’ matrix.

Fine Microstructure of a Mechanically Alloyed Oxide Dispersion Strengthened Nickel-Base Superalloy

1977 ◽  
Vol 35 ◽  
pp. 298-299
Author(s):  
Jordi Marti ◽  
Timothy E. Howson ◽  
David Kratz ◽  
John K. Tien
Keyword(s):  
Solid Solution ◽  
Volume Fraction ◽  
Stress Rupture ◽  
Oxide Dispersion Strengthened ◽  
Solid Solution Alloy ◽  
Oxide Dispersion ◽  
Creep And Stress Rupture ◽  
Mechanically Alloyed ◽  
Fine Microstructure ◽  
Nickel Base

The previous paper briefly described the fine microstructure of a mechanically alloyed oxide dispersion strengthened nickel-base solid solution. This note examines the fine microstructure of another mechanically alloyed system. This alloy differs from the one described previously in that it is more generously endowed with coherent precipitate γ forming elements A1 and Ti and it contains a higher volume fraction of the finely dispersed Y2O3 oxide. An interesting question to answer in the comparative study of the creep and stress rupture of these two ODS systems is the role of the precipitate γ' in the mechanisms of creep and stress rupture in alloys already containing oxide dispersoids.The nominal chemical composition of this alloy is Ni - 20%Cr - 2.5%Ti - 1.5% A1 - 1.3%Y203 by weight. The system receives a three stage heat treatment-- the first designed to produce a coarse grain structure similar to the solid solution alloy but with a smaller grain aspect ratio of about ten.

AISI No. 664

Alloy Digest ◽  
1981 ◽  
Vol 30 (7) ◽  
Keyword(s):  
High Temperature ◽  
Stress Rupture ◽  
Heat Treating ◽  
Good Combination ◽  
Creep And Stress Rupture ◽  
High Temperature Alloy ◽  
Vacuum Melting ◽  
Stress Rupture Properties ◽  
Nickel Base ◽  
Rupture Properties

Abstract AISI No. 664 is a nickel-base high-temperature alloy that can be precipitation hardened because of its contents of aluminum and titanium. Vacuum melting is used in its production to provide excellent quality and reproducability. It is used for applications requiring a good combination of creep and stress-rupture properties up to about 1500 F. Typical applications are gas-turbine components, airframes and fasteners. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ni-269. Producer or source: Nickel alloy producers.

TECHALLOY WASPALOY

Alloy Digest ◽  
1977 ◽  
Vol 26 (4) ◽  
Keyword(s):  
Elevated Temperatures ◽  
Rupture Strength ◽  
Stress Rupture ◽  
High Strength ◽  
Heat Treating ◽  
Age Hardening ◽  
Solid Solution Strengthening ◽  
Solution Strengthening ◽  
Nickel Base ◽  
Corrosion And Oxidation

Abstract TECHALLOY WASPALOY, a nickel-base austenitic precipitation-hardenable alloy, derives its high strength at elevated temperatures from additions of the solid-solution strengthening elements molybdenum, cobalt and chromium and from aluminum and titanium which produce age hardening. Boron and zirconium additions also have been made to obtain optimum stress-rupture strength. It has excellent strength and good resistance to corrosion and oxidation at least to 1600 F. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness and creep. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ni-243. Producer or source: Techalloy Company Inc..

Modeling the Tensile Behaviour of a SiC/SiC Composite by Master Curves

2000 ◽  
Author(s):  
J. Shi
Keyword(s):  
Master Curve ◽  
Ceramic Matrix Composites ◽  
Test Material ◽  
Tensile Behaviour ◽  
Matrix Composites ◽  
Test Results ◽  
Master Curves ◽  
The Past ◽  
Test Parameters ◽  
Tensile Data

Scatter in test results is common for relatively brittle materials such as ceramic matrix composites. The scatter may come from differences in material processing conditions, specimen machining/handling and from variations in test parameters for nominally the same test material. Large scatter in test results makes material modeling difficult. In the past, master curve concepts have been proposed to reduce scatter in tensile data and to interpret fatigue/creep results. In this paper, one such concept is examined in detail by applying it to the recent tensile test results of a SiC/SiC composite. It was found that the way to construct master curves did not apply to the CMC studied and thus a new master curve was developed to better represent the tensile data. In addition, the test data were analysed statistically based on the new master curve.

Prediction of Long Term Stress Rupture Data for 2124

2006 ◽  
Vol 519-521 ◽  
pp. 1041-1046 ◽  
Author(s):  
Brian Wilshire ◽  
H. Burt ◽  
N.P. Lavery
Keyword(s):  
Q Methodology ◽  
Fracture Behavior ◽  
Stress Rupture ◽  
Creep Data ◽  
Short Term ◽  
Rupture Data ◽  
Term Creep ◽  
Term Data ◽  
Short Term Creep

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.

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