CF/SCC Interaction on Structural Materials for LWR in High Temperature Water

2002 ◽  
Author(s):  
Yasuyuki Katada ◽  
Shigeo Ohashi
Keyword(s):  
High Temperature ◽  
Water Type ◽  
Loading Test ◽  
High Temperature Water ◽  
Rate Test ◽  
Loading Modes ◽  
Type 3 ◽  
Temperature Water

A test apparatus was developed to study the interaction between corrosion fatigue (CF) and stress corrosion cracking (SCC) in high-temperature water simulated boiling water reactor environment. Tests were conducted using 1/2T-CT samples of both low alloy and sensitized stainless steels under 3 different types of loading at 0.2–8 ppm in dissolved oxygen concentrations at 563 K in water. Type 1 was a normal cyclic loading test of constant amplitude, Type 2 a monotonic constant loading rate test, and Type 3 a combination of Type 1 + Type 2 loading modes. In the low alloy steel, no striking interaction was observed between CF and SCC, whereas in the case of Type 3 loading condition crack growth rates of the sensitized stainless steel were as much as 3 times higher than those for Type 1 + Type 2. The mechanism of the CF and SCC interaction is discussed.

Research on Effect of Alloy Elements on Equilibrium and Properties of Ni-Cr-Co Type Nickel-Based Superalloy

2016 ◽  
Vol 849 ◽  
pp. 513-519
Author(s):  
Qing Quan Zhang ◽  
Ming Yang Li ◽  
Ran Wei ◽  
Hui Yun Wu ◽  
Zhen Rui Li
Keyword(s):  
High Temperature ◽  
Room Temperature ◽  
High Temperature Strength ◽  
Nickel Based Superalloy ◽  
Type 3 ◽  
Room Temperature Strength ◽  
Super Alloy ◽  
Type Nickel

Ni-Cr-Co type Nickel-based super alloy Inconel 740H was studied. The effect of Nb, Al and Ti on the equilibrium of this alloy was analyzed by JMatPro software. The amount of Ti and Nb should be controlled by 1.50wt.%, and meanwhile, Al should be 1.0-2.0wt.%. If Mo and W were added the amount of Mo should be in the range of 1.0-2.0wt. %, and W should be about 1.0wt.%. Based on these results, three types of new alloys were designed, which contain Ni-Cr-Co-Mo type (1#), Ni-Cr-Co-W type (2#) and Ni-Cr-Co-Mo-W type (3#). Compared with the Ni-Cr-Co type Inconel 740H alloy, the room temperature strength, high temperature strength and high temperature durable performance of the three new alloys improved, which can provide the evidence and reference to optimize the chemical composition of Inconel 740H alloy, i.e., adding 1.50wt.% Mo and 1.0wt.% W individually or together.

Origin and circulation of water types on the 26.00 sigma-t surface of the south-west Pacific

1968 ◽  
Vol 19 (2) ◽  
pp. 107 ◽  
Author(s):  
DJ Rochford
Keyword(s):  
Oxygen Content ◽  
Water Type ◽  
The South ◽  
West Pacific ◽  
Water Types ◽  
South West ◽  
Tasman Sea ◽  
Type 3

CSIRO hydrological data from the south-west Pacific (0-45�S., 140°E.-160� W.) during 1960-67 have been used to calculate annual means of salinity and oxygen, within 5� squares, on the 26.00 sigma-t surface. In addition, for some squares it was possible to calculate mean summer (December-February) and mean winter (July- September) values of salinity and oxygen. From the annual means the salinity-oxygen relations were used to characterize four water types. Water type 1 of tropical origin had a salinity of 35.03‰ and an oxygen content of 3.20 ml/l. Water type 2, also of tropical origin, had a salinity of 35.23‰ and an oxygen content of 2.30 ml/l. Water type 3 of subtropical origin had a salinity of 35 +66‰ and an oxygen content of 5.45 ml/l. Water type 4 of Subantarctic origin had a salinity of 34.80‰ and an oxygen content of 6.00 ml/l. The ultimate origins of water types 1 and 2 are thought to be at considerable distances from the south-west Pacific region. Water type 1 is suggested as a mixture of waters of the North Equatorial Pacific, to the west of about 160°W., and waters of type 3 originating in the south Tasman Sea and other regions of the south Pacific. Water type 2 forms at around 16O°W., by mixing of eastern tropical Pacific waters and water type 3. It is thought that water types 1 and 2 form at different times of the year depending upon the extent of meridional or zonal flow in the central Equatorial region. Water types 3 and 4, however, are formed by southward spreading and winter cooling at the surface of subtropical waters, and by northward spreading and summer warming at the surface of Subantarctic waters, respectively. These two water types are therefore of south-west Pacific origin. Generally in the Tasman Sea (south of 25�S.), the concentration of water type 1 is very low (less than 10%); of water type 2 only a little higher (20-30%), but that of water type 3 is high (around 60-75%). The concentration of water type 4 was much greater (40%) off the west coast of South Island, New Zealand, than off the east coast of Tasmania (15 %). Seasonal pulses in the concentrations of water types 1 and 2 along 170�E., between 0 and 15�S., are in phase with seasonal changes in the concentration of these two water types in the Tasman and Coral Seas, if these water types spread southward at about 10 cm/sec. Summer increases in the concentration of water type 3 in the Tasman Sea off New Caledonia have been explained by the northward spreading of the previous winter's accumulation of this water type in the central Tasman Sea.

Crack Initiation and Growth Analysis by Direct Optical Observation during SSRT in High Temperature Water

CORROSION ◽  
1984 ◽  
Vol 40 (3) ◽  
pp. 120-126 ◽  
Author(s):  
Takashi Kawakubo ◽  
Mamoru Hishida
Keyword(s):  
High Temperature ◽  
Crack Initiation ◽  
Crack Growth ◽  
Optical Observation ◽  
Observation System ◽  
Slow Strain Rate Test ◽  
Cracking Behavior ◽  
High Temperature Water ◽  
Rate Test ◽  
Temperature Water

Abstract The stress corrosion cracking behavior during the slow strain rate test (SSRT) has been investigated in high temperature water. SSRTs were performed on center-notched thin plate specimens of sensitized Type 304 stainless steel. A direct optical observation system consisting of single crystal sapphire windows was employed to separate the SCC into an initiation and a growth stage, and to measure the crack growth rate. Effects of the extension rate, test temperature, and dissolved oxygen concentration on the crack initiation and growth were examined. The crack growth data were analyzed with different variables, including the elastic plastic fracture mechanics parameters. The best interpretation of the crack growth rates is obtained by plotting them vs the time differential of J-integral, which is an estimate of the crack tip deformation rate during SSRT.

FUNCTIONAL STATUS AND ADAPTIVE POTENTIAL IN FOREIGN STUDENTS WITH DIFFERENT TYPES OF VEGETATIVE REGULATION DURING TUITION

2020 ◽  
pp. 118-126
Author(s):  
A.M. Satarkulova
Keyword(s):  
Heart Rate ◽  
Foreign Students ◽  
Autonomic Regulation ◽  
The Body ◽  
Functional Changes ◽  
Different Types ◽  
Type 3 ◽  
Adaptive Abilities

The assessment and dynamic control over students’ status is a very important task. It allows timely detection of prenosological status prior to pathology and health maintenance in students. The objective of the paper is to assess the adaptive abilities of the body, to analyze changes in heart rate variability indicators in students with various types of autonomic regulation, to identify prenosological status and precursory pathological symptoms. Materials and Methods. The study enrolled 302 students from India, aged 21.54±1.43. Programming complex «Psychophysiologist» was used to register the main HRV parameters within 5 minutes. Health status was evaluated according to the index of functional changes and the scale of functional states. Results. N.I. Shlyk (2009) distinguished two groups of students with different types of autonomic regulation: type 1 (53 %) with moderate and type 2 (5 %) with marked characteristics of central regulation profile, type 3 (35 %) with moderate and type 4 (7 %) with marked characteristics of autonomous regulation profile. Main parameters of HRV and adaptation potential were defined for each student.All the parameters characterized functional and health status. Conclusions. It was shown that 82 % of trial subjects (type 1), 53 % (type 2), 94 % (type 3) and 95 % (type 4) demonstrated satisfactory adaptation and their physiological processes were at an optimal level. 18 % of students (type 1) demonstrated reduced adaptive abilities of the body. Moreover, they were under moderate stress. 47 % of subjects (type 2) were also under a significant stress, which was proven by excessively high SI, low SDNN and TP, and an increased index of functional changes. 5 % of students (type 4) revealed dysfunctional characteristics in the heart rhythm, peculiar to pathology. Keywords: foreign students, heart rate variability, types of autonomic regulation, adaptation potential, functional status. Оценка состояния студентов и динамический контроль за ним является важной задачей, поскольку позволяет своевременно выявлять у студентов донозологические состояния, предшествующие патологии, и способствовать сохранению здоровья. Цель. Оценка адаптивных возможностей организма, анализ изменений показателей вариабельности сердечного ритма у студентов с различными типами вегетативной регуляции, выявление донозологических состояний и ранних признаков патологии. Материалы и методы. В исследовании участвовало 302 студента в возрасте 21,54+1,43 года из Индии. Регистрировались основные параметры ВСР в течение 5 мин с использованием программно-аппаратного комплекса «Психофизиолог». Состояние и уровень здоровья оценивались по индексу функциональных изменений и шкале функциональных состояний. Результаты. По способу, предложенному Н.И. Шлык, выделены группы студентов с различными типами вегетативной регуляции: I (53 %) и II типы (5 %) – с умеренным и выраженным преобладанием центрального контура регуляции соответственно, III (35 %) и IV типы (7 %) – с умеренным и выраженным преобладанием автономного контура регуляции соответственно. У каждого из студентов определены основные параметры ВСР и адаптационного потенциала, характеризующие функциональное состояние и уровень здоровья. Выводы. Показано, что для 82 % обследуемых с I типом, 53 % со II типом, 94 % c III типом и 95 % с IV типом регуляции характерно состояние удовлетворительной адаптации, физиологические процессы сохраняются на оптимальном уровне. В группе студентов I типа у 18 % студентов адаптивные возможности организма снижены, выявлено состояние умеренного напряжения. У 47 % обследуемых II типа также зафиксировано состояние резко выраженного напряжения, индикатором которого является чрезмерно высокое значение SI, низкие величины SDNN и ТP, повышенное значение индекса функциональных изменений. В группе студентов с IV типом у 5 % учащихсяв регуляции ритма сердца выявлены дисфункциональные признаки, характерные для патологии. Ключевые слова: иностранные студенты, вариабельность сердечного ритма, типы вегетативной регуляции, адаптационный потенциал, функциональное состояние.

POLIOMYELITIS IN CANADIAN ESKIMOS: LABORATORY STUDIES. V. TYPE 1 AND TYPE 3 POLIOMYELITIS ANTIBODY LEVELS IN BAFFIN ISLAND ESKIMOS

1954 ◽  
Vol 32 (1) ◽  
pp. 119-125
Author(s):  
W. Wood ◽  
Eina M. Clark ◽  
F. T. Shimada ◽  
A. J. Rhodes
Keyword(s):  
Medical Records ◽  
Baffin Island ◽  
Tissue Cultures ◽  
Laboratory Studies ◽  
Poliomyelitis Virus ◽  
Antibody Titers ◽  
Antibody Levels ◽  
Type 3

Studies on the basic immunology of poliomyelitis in Canadian Eskimos have been continued. Some 87 sera collected from Eskimos at Pangnirtung, Baffin Island, have been examined for the presence of Type 1 and Type 3 poliomyelitis antibody by quantitative tests in tissue cultures. The same sera were previously examined for Type 2 antibody by quantitative tests in mice. The results of the three determinations are now presented together for comparison. These sera came from Eskimos aged 2 to 72 years of age. None of the Eskimos showed any evidence of paralysis. Examination of the medical records did not suggest that any paralytic disease had been present in this part of Baffin Island. Very few of the sera showed the presence of poliomyelitis antibody; thus, Type 1 antibody was demonstrated in the sera of 8%, Type 2 antibody in the sera of 9%, and Type 3 antibody in the sera of 14%. No significant number of Eskimos below the age of 45 years had acquired poliomyelitis antibody. The antibody titers mostly ranged between 10−1.0 and 10−2.0, and were significantly lower than the titers customarily found in recently paralyzed cases. These findings suggest that poliomyelitis infection occurred in Pangnirtung Eskimos many years before the date on which the samples were taken (1951). These results point to the worldwide prevalence of the three types of poliomyelitis virus.

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