Long-Term Creep Data Prediction for Type 316H Stainless Steel

Impressive data sets have been produced for 316H stainless steel (18Cr–12Ni–Mo with up to 0.08C) by the National Institute for Materials Science (NIMS), Japan, to reveal the dependencies on stress and temperature of the high-temperature creep and creep fracture behavior of nine batches of tube, six of bar and two of plate. Using these long-term property values, the stresses to produce failure in 100,000 h at various plant exposure … Continue reading Long-Term Creep Data Prediction for Type 316H Stainless Steel

Advanced Procedures for Long-Term Creep Data Prediction for 2.25 Chromium Steels

A critical review of recent creep studies concluded that traditional approaches such as steadystate behavior, power law equations, and the view that diffusional creep mechanisms are dominant at low stresses should be seriously reconsidered. Specifically, creep strain rate against time curves show that a decaying primary rate leads into an accelerating tertiary stage, giving a minimum rather than a secondary period. Conventional steady-state mechanisms should therefore be abandoned in favor … Continue reading Advanced Procedures for Long-Term Creep Data Prediction for 2.25 Chromium Steels

Variability in the mechanical properties and processing conditions of a high strength low alloy steel

Variability in the mechanical properties of steel strip has a significant effect on the structural performance of manufactured components. This study provides a statistical analysis of the variability in yield strength, Ultimate Tensile Strength (UTS) and elongation to failure by examining the chemistry of the cast and rolling conditions of the steel strip. This type of data can play a key role in the development of robust and … Continue reading Variability in the mechanical properties and processing conditions of a high strength low alloy steel

The influence of mechanical and CO2 laser cut-edge characteristics on the fatigue life performance of high strength automotive steels

The cut-edge characteristic properties of automotive structures formed during the mechanical blanking and laser-cutting processes significantly influence fatigue life performance. This factor is becoming increasingly important as S355MC and DP600 high strength steels (HSS) grades under investigation exhibit an increased sensitivity to fatigue cracks initiating from cut-edge regions. It was determined that by manipulating the critical cutting process parameters, clearance in terms of mechanical blanking, and by controlling the interrelationship … Continue reading The influence of mechanical and CO2 laser cut-edge characteristics on the fatigue life performance of high strength automotive steels

Creep and creep fracture of 2.25Cr–1.6W steels (Grade 23)

The creep and creep rupture properties of Grade 23 (2.25Cr–1.6W) steels have been analysed for material produced in pipe (P23) and tube (T23) forms. The similarities and differences in the behaviour patterns observed for the pipe and tube products are then discussed in terms of the dislocation processes governing creep strain accumulation and the various damage phenomena causing the onset of tertiary creep and eventual … Continue reading Creep and creep fracture of 2.25Cr–1.6W steels (Grade 23)

Long term creep life prediction for Grade 22 (2.25Cr–1Mo) steels

Using new data analysis procedures, 100000h creep strengths are estimated by extrapolation of stress rupture values with creep lives, 5000h for Grade 22 tube as well as for annealed/ tempered and quenched/tempered plates. In addition to allowing accurate prediction of long term strengths, the resulting property sets can be discussed sensibly in terms of the deformation and damage processes controlling creep and creep fracture.   M. T. Whittaker and … Continue reading Long term creep life prediction for Grade 22 (2.25Cr–1Mo) steels