FEASIBILITY OF DETECTING IMPENDING FATIGUE FAILURE oo IN METALS BY OBSERVATION OF P SURFACE CHEMICAL AND PHYSICAL PHENOMENA
ثبت نشده
چکیده
The purpose oi' the study was to investigate, through laboratory tests, the potential for developing fatigue indicators for which some merit was evident from prior research. The response of photographic emulsions, phosphor coatings,and chemical indicator coatings to physical and surface-chemical reactions associated with fatigue damage in 2024-T3 aluminum was investigated. Many indicators were examined for their ability to meet the Army's requirements (1) under field conditions, (2) for long periods, and (3) for detection of damage that is characteristic of both highand low-stress cycling. None of the candidate indicators was developed to a point where it showed promise for meeting these requirements during the contract period. Further investigation is recommended for one color indicator that was only briefly tested. Surface replication followed by microscopic examination was found to provide useful information on progressing fatigue damage,and effort directed toward developing practical methods for relating replica data to remaining life-to-failure is recommended.
منابع مشابه
Investigate the effect of distance from source and species type on the absorption ability of heavy metals by tree species around Nahavand cement factory
This study aims at investigating the effect of distance from source, species type and soil physical chemical properties on the absorption ability of heavy metals by tree species around the Nahavand cement factory. In the present research, soil and tree leaf (Pseudoacacia L, Populus nigra L, Elaeagnus angustifolia L, Fraxinus excelsior and Thuja orientalis L) samples were taken from 300, 500, 80...
متن کاملOptimization of Biodiesel Production Using Immobilized Candida Rugosa Lipase on Magnetic Fe3O4-Silica Aerogel
Hydrophobic magnetic silica aerogel was used as a support to immobilize Candida rugosa lipase by adsorption method. Physical and chemical properties of the support and immobilized lipase were determined by Field Emission Scanning Electron Microscope (FESEM), Brunauer–Emmett–Teller (BET) analysis and Fourier Transform InfraRed (FT-IR) spectroscopy and the results showed that the lipase was s...
متن کاملمقایسه میزان خستگی، کمیت و کیفیت خواب در نوبت کاران پیر و جوان
Background: It is well known that shift work produces fatigue. This effect is enhanced in seniors and could be potentiated by physical and psychosocial job demands. The aim of this study was to investigate the combined effects of work-related risk factors, age and shift work on fatigue. Materials and methods: The field study was performed based on a questionnaire about sleep characteristics, e...
متن کاملGroundwater Contamination by Heavy Metals in Water Resources of Shiraz Area
Lack of sewage collection systems, percolation of surface waters, and seepage of wells have raised the groundwater table in Shiraz area in the south of Iran. The growing population generates environmental pollution resulting in the degradation of the quality of surface and groundwaters used for agriculture. Inorganic and organic pollutants have been traced in Shiraz water resources. Heavy metal...
متن کاملInvestigation of Heavy Metal Contamination in the Surface Sediments of Anzali wetland in North of Iran
Over the last few decades, Anzali wetland has been at risk of pollutants, especially from heavy metals. The present research analyzes some physical and chemical properties and heavy metals concentration in 27 points in nine stations of Anzali wetland. The samples of each station have been mixed, acidic digested, and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The mean con...
متن کامل