Maximum inclusion size in two clean steels Part 1 Comparison of maximum size estimates by statistics of extremes and generalised Pareto distribution methods

Abstract Estimation of the maximum size of inclusions in a large volume of steel is an important issue in relation to clean steels. Statistics of extremes can be used for the estimation, and one such method, developed by Murakami and coworkers, is now used by the steel industry for characterising steel specimens. An alternative method, based on the generalised Pareto distribution, has recently been developed and has advantages. A key factor in such methods is the extent to which they can discriminate between steels of different cleanness levels. In the present paper, this discrimination is demonstrated using data from polished metallographic specimens. The confidence limit intervals are estimated using the maximum likelihood method.

[1]  Y. Murakami,et al.  Quantitative evaluation of effects of non-metallic inclusions on fatigue strength of high strength steels. II: Fatigue limit evaluation based on statistics for extreme values of inclusion size , 1989 .

[2]  Stefano Beretta,et al.  STATISTICAL ANALYSIS OF DEFECTS FOR FATIGUE STRENGTH PREDICTION AND QUALITY CONTROL OF MATERIALS , 1998 .

[3]  Yukitaka Murakami,et al.  Critical Review of the Inclusion Rating by JIS-G-0555 Method and New Inclusion Rating Based on Statistics of Extreme and Its Applications , 1993 .

[4]  C. Anderson,et al.  The Measurement of Averages and Extremes of Environmental Variables , 1994, Journal of Research of the National Institute of Standards and Technology.

[5]  C. Anderson,et al.  Critical Levels of Ozone Over the United Kingdom: Mapping Aggregate Exceedances Over Moderate to High Thresholds , 1994 .

[6]  I. T. Young,et al.  Quantitative Microscopy , 1984, Definitions.

[7]  Helen V. Atkinson,et al.  Application of the generalized pareto distribution to the estimation of the size of the maximum inclusion in clean steels , 1999 .

[8]  Masayuki Takada,et al.  Super-long life tension–compression fatigue properties of quenched and tempered 0.46% carbon steel , 1998 .

[9]  Y. Murakami.  Inclusion Rating by Statistics of Extreme Values and Its Application to Fatigue Strength Prediction and Quality Control of Materials , 1994, Journal of research of the National Institute of Standards and Technology.

[10]  Masahiro Endo,et al.  Defect tolerant design of automotive components , 1997 .

[11]  C. W. Anderson,et al.  Comparison of extreme value statistics methods for predicting maximum inclusion size in clean steels , 1999 .

[12]  C. Anderson.  The Aggregate Excess Measure of Severity of Extreme Events , 1994, Journal of research of the National Institute of Standards and Technology.

[13]  Y. Murakami,et al.  Effects of defects, inclusions and inhomogeneities on fatigue strength , 1994 .

[14]  K. Kawakami,et al.  Quantitative evaluation of effects of shape and size of artificially introduced alumina particles on the fatigue strength of 1.5NiCrMo (En24) steel , 1991 .

[15]  David Walshaw,et al.  Getting the Most From Your Extreme Wind Data: A Step by Step Guide , 1994, Journal of research of the National Institute of Standards and Technology.

[16]  Y. Murakami,et al.  Quantitative evaluation of effects of non-metallic inclusions on fatigue strength of high strength steels. I: Basic fatigue mechanism and evaluation of correlation between the fatigue fracture stress and the size and location of non-metallic inclusions , 1989 .

[17]  T. Toriyama,et al.  Effects of Nonmetallic Inclusions and Small Surface Pits on the Fatigue Strength of a High Strength Steel at Two Hardness Levels , 1991 .

[18]  Y. Tomita.  Effect of desulphurization and calcium treatments on the inclusion morphology of 0.4C-Cr-Mo-Ni steel , 1994 .

[19]  P. Prescott,et al.  Maximum likeiihood estimation of the parameters of the three-parameter generalized extreme-value distribution from censored samples , 1983 .

[20]  Yukitaka Murakami,et al.  Instructions for a New Method of Inclusion Rating and Correlations with the Fatigue Limit , 1994 .

[21]  T. Toriyama,et al.  Effects of Chemical Composition of Nonmetallic Inclusions on Fatigue Strength of High Strength Steels , 1993 .