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Manson, S. S.

Publications and source records attributed to Manson, S. S..

At least 55 records · Page 3

The challenge to unify treatment of high-temperature fatigue - A partisan proposal based on strainrange partitioning

The strainrange partitioning concept divides the imposed strain into four basic ranges involving time-dependent and time-independent components. It is shown that some of the results presented at the symposium can be better correlated on the basis of this concept than by alternative methods. It is also suggested that methods of data generation and analysis can be helpfully guided by this approach. Potential applicability of the concept to the treatment of frequency and hold-time effects, environmental influence, crack initiation and growth, thermal fatigue, and code specifications are briefly considered. A required experimental program is outlined.

Manson, S. S.↗

Metal fatigue damage - Mechanism, detection, avoidance, and repair.

Collection of theoretical and experimental studies covering basic mechanisms of fatigue in the subcreep and creep ranges, fatigue damage detection, field practices for fatigue damage repair in jet engine components, and fatigue damage avoidance and control. Individual items are abstracted in this issue.

Manson, S. S.↗

Avoidance, control, and repair of fatigue damage.

A summary is presented of various methods available to the engineer for dealing with fatigue problems. Design, metallurgical, and service factors are considered. An attempt is made to provide a rational basis for each approach, resorting in each case to an understanding of the fundamental mechanism of the fatigue process.

Manson, S. S.↗

Creep-fatigue analysis by strain-range partitioning.

The framework of a new method is outlined for treating creep-fatigue behavior of metals. Inelastic strain-ranges are partitioned into the components of (1) completely reversed plasticity, (2) tensile plasticity reversed by compressive creep, or tensile creep reversed by compressive plasticity, and (3) completely reversed creep. Each of these components is shown to be related to cyclic life by a Manson-Coffin type power-law equation. A linear life fraction rule is used to combine the damaging effects of the individual components enabling the prediction of life. Test results are presented for a 2.25 Cr-1 Mo steel as well as limited information for a Type 316 stainless steel.

Manson, S. S.↗

The role of creep in high temperature low cycle fatigue.

The significance of the role that creep can play in governing high-temperature, low-cycle fatigue resistance is investigated by conducting strain cycling tests on two high-temperature stainless steel alloys and making concurrent measurements of stress, temperature, and strain at various frequencies. The results are then analyzed in terms of damage imposed by creep and fatigue components. It is shown that creep can play an important and sometimes dominant role in low cycle fatigue at high temperatures. The results of the study include the findings that: (1) the simple life-fraction theory described is adequate for calculating creep damage when the cyclic creep rupture curve is used as a basis for analysis; (2) a method of universal slopes originally developed for room temperature use is sufficiently accurate at high temperature to be used to calculate pure fatigue damage; and (3) a linear creep-fatigue damage rule can explain the transitions observed from one failure mode to another.

Manson, S. S.↗