Viscoplastic Behavior of a Notch Root at 650°C: ISDG Measurement and Finite Element Modeling

1996 ◽  
Vol 118 (1) ◽  
pp. 88-93 ◽  
Author(s):  
Keyu Li ◽  
William N. Sharpe
Keyword(s):  
Finite Element ◽  
Notch Root ◽  
Tensile Creep ◽  
Strain Gages ◽  
Controlled System ◽  
Interferometric Technique ◽  
Pure Silicon ◽  
Nickel Based Superalloy ◽  
Silicon Coating ◽  
Computer Controlled

Viscoplastic behavior of the nickel-based superalloy, Inconel 718, at a notch root has been investigated by conducting isothermal tensile, creep and cyclic elastoplastic tests at 650°C which is the working temperature of the material in aircraft engines. A laser-based interferometric technique was extended to measure biaxial strains over a gage length of 150 μm at the notch root; the computer controlled system permits real-time measurements. A thin-film pure silicon coating and an argon atmosphere were used to prevent oxidation of the reflective indentations that serve as the strain gages. The measured strains were used to evaluate the Bodner-Partom constitutive model which was incorporated into the ABAQUS finite element code. Material constants in the model were determined from uniaxial tests on smooth specimens. The predicted strains agree reasonably well with the measured ones for all three kinds of loadings.

Biaxial Creep Strains at Notch Roots—Measurement and Modeling

1997 ◽  
Vol 119 (1) ◽  
pp. 46-50 ◽  
Author(s):  
H. Zeng ◽  
W. N. Sharpe
Keyword(s):  
Finite Element ◽  
Measurement Technique ◽  
Zirconium Alloy ◽  
Notch Root ◽  
Finite Element Code ◽  
Smooth Specimen ◽  
Interferometric Technique ◽  
Biaxial Creep ◽  
Creep Strains

Biaxial strains were measured at the roots of single notches in zirconium alloy specimens under loading and creep conditions (up to 1200 hours) at 250°C. A laser-based interferometric technique was used; details of the measurement procedures are given in another paper. Here, the Bodner model is incorporated into the ABAQUS finite element code and used to predict the biaxial strains at the notch root during loading and for a creep duration of 100 hours. The strains during loading agree quite well with the measured ones while the predicted creep strains are smaller. This discrepancy is attributed to the lack of precision in determining the constants for the Bodner model from smooth-specimen tests. Both the measurement technique and the Bodner model are well-suited for studies of notch response.

The Design of Firing Mechanism Controlling Research of Natural Gas Vehicle Cylinder

2013 ◽  
Vol 333-335 ◽  
pp. 2044-2051
Author(s):  
Wei Pu Xu ◽  
Yi Ting Liu
Keyword(s):  
Natural Gas ◽  
Data Acquisition ◽  
Wireless Network ◽  
Fire Test ◽  
General Idea ◽  
Security Risks ◽  
Controlled System ◽  
Video Systems ◽  
Computer Controlled ◽  
Natural Gas Vehicle

This article described the current situation and the security risks of the natural gas vehicle cylinders, which introduced the principle of the fire test, proposed the general idea of the fire test equipment. Wireless network, video systems, data acquisition systems and computer-controlled system of the equipment researching are also introduced.

Investigation on endurance evaluation of a portal crane: experimental, theoretical and finite element analysis

2020 ◽  
Vol 62 (4) ◽  
pp. 357-364
Author(s):  
Yusuf Aytaç Onur ◽  
Hakan Gelen
Keyword(s):  
Finite Element ◽  
Critical Points ◽  
Maximum Stress ◽  
Strain Gages ◽  
Finite Element Analyses ◽  
Element Analysis ◽  
Element Simulation ◽  
Main Girder ◽  
Stressed Component ◽  
Portal Crane

Abstract In this study, the stress on portal crane components at various payloads has been investigated theoretically, numerically and experimentally. The portal crane was computer-aided modeled and finite element analyses were performed so that the most stressed points at the each trolley position investigated on the main girder could be determined. In addition, the critical points were marked on the portal crane, and strain gages were attached to the those critical points so that stress values could be experimentally determined. The safety factor values at different payloads were determined by using finite element simulation. Results indicate that the most stressed component in the examined portal crane is the main girder. Experimental results indicate that the maximum stress value on the main girder is 3.05 times greater than the support legs and 8.99 times larger than the rail.

scholarly journals A Computer-Controlled System for Ice-Fabric Analysis on a Rigsby Stage

1988 ◽  
Vol 10 ◽  
pp. 92-94 ◽  
Author(s):  
Manfred A. Lange
Keyword(s):  
Tilt Angle ◽  
Ice Core ◽  
Data Bank ◽  
Integrated System ◽  
Controlled System ◽  
Thin Sections ◽  
Fabric Analysis ◽  
Data Files ◽  
Computer Controlled ◽  
Electronic Sensors

An integrated system for ice-fabric analysis on a Rigsby stage is described. The system consists of a regular Rigsby stage fitted with two opto-electronic sensors for assessment of azimuth and the tilt angle of each individual grain. Signals from the sensors are transmitted to a computer terminal via an interface box, which facilitates transformation of Gray-coded data to ASCII data records. The terminal is hooked up to a main-frame computer (VAX 750), where the digitized angles of the c-axis orientations of individual thin sections are stored in separate data files. These files are compatible with other already existing files containing additional ice-core data and thus become part of an extensive data bank. Appropriate software has been developed to produce, among other things, plots of c-axis orientations in a Schmidt net.

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