Nondestructive Assessments of Residual Stresses in Railroad Wheel Rim by Acoustoelasticity

1985 ◽  
Vol 107 (3) ◽  
pp. 281-287 ◽  
Author(s):  
H. Fukuoka ◽  
H. Toda ◽  
K. Hirakawa ◽  
H. Sakamoto ◽  
Y. Toya
Keyword(s):  
Residual Stress ◽  
Fem Analysis ◽  
Railroad Wheel ◽  
Velocity Difference ◽  
Average Value ◽  
Acoustic Anisotropy ◽  
Wheel Rim ◽  
Principal Directions ◽  
Acoustoelasticity Method ◽  
Destructive Methods

Residual stress in the rim of railroad solid wheel was measured nondestructively by an acoustoelasticity method which makes use of the birefringent effect. The acoustic anisotropy is a fractional velocity difference of two shear waves polarized perpendicularly in principal directions and is proportional to the principle stress difference. However, in order to get the residual stress nondestructively, the contribution of texture anisotropy has to be separated from the total acoustic anisotropy. The scatter of the texture anisotropy was investigated using seven wrought wheels, four of which were used for drag brake tests that were to change the residual stress level. The initial and after braked residual stress was analyzed by acoustoelasticity, and the results were compared with the conventional methods and FEM analysis. Conclusively, it is expected through this study that the residual stress averaged through thickness in the rim can be assessed nondestructively by using the average value of the texture anisotropy in the rim within 40 MPa of difference compared with the estimation by conventional destructive methods.

scholarly journals Nondestructive evaluation of residual stress in railroad wheel rim with EMATs.

1990 ◽  
Vol 110 (8) ◽  
pp. 866-872
Author(s):  
Riichi Murayama ◽  
Kazuo Fujisawa ◽  
Sadao Yonehara
Keyword(s):  
Residual Stress ◽  
Nondestructive Evaluation ◽  
Railroad Wheel ◽  
Wheel Rim

Development of Railroad Wheel Rim Axial Residual Stress in Heavy Axle Load Service

2013 ◽  
Author(s):  
Cameron Lonsdale ◽  
John Oliver ◽  
Rama Krishna Maram ◽  
Scott Cummings
Keyword(s):  
Residual Stress ◽  
Tensile Stress ◽  
Railroad Wheel ◽  
Stress Profile ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wheel Rim ◽  
Axial Tensile ◽  
Axial Residual Stress ◽  
Class C

Vertical split rim (VSR) failures remain a failure mode for wheels in North America, and are of concern to wheel manufacturers and railroads alike. Both forged and cast wheels have suffered VSRs in service. Extensive testing during the last several years, using x-ray diffraction techniques, has shown the axial residual stress pattern within the railroad wheel rim is significantly different for new AAR Class C wheels vs. AAR Class C wheels that have failed due to a VSR, and non-failed AAR Class C wheels that have been operating in service. VSRs almost always begin at areas of tread damage, resulting from shelling or spalling, and cracking propagates into the rim section under load. At the rim locations tested, the as-manufactured wheels have a relatively “flat” axial residual stress profile, compressive but near neutral, caused by the rim quenching operation, while wheels that have been in service have a layer of high axial compressive stress at the tread surface, and a balancing zone of axial tensile stress underneath. The magnitude and direction of this axial tensile stress is consistent with the crack propagation of a VSR failure. When cracks from tread surface damage propagate into this subsurface axial tensile zone, a VSR can occur under sufficient additional service loading, such as loads caused by in-service wheel/rail impacts from tread damage. Further, softer Class U (untreated) wheels, removed from service and tested, were found to have a balancing axial tensile stress layer deeper below the tread surface than that found in used Class C wheels. This paper describes recent x-ray diffraction testing to measure the axial residual stress profile in wheel rims operated in the Facility for Accelerated Service Testing (FAST) train at the Transportation Technology Center (TTC), in Pueblo, CO. The goal of the testing was to determine the development rate and magnitude of wheel rim axial residual stress, as a function of known load and service mileage. Four new Class C wheelsets and four new Class U wheelsets were placed in service under the FAST train, and these wheelsets were subsequently removed at various mileage levels for evaluation. Two radial rim slices were cut from each wheel at each mileage level, and x-ray diffraction was used to measure the axial residual stress within the wheel rim section. The last two Class C wheelsets and last two Class U wheelsets were also exposed to an extended drag braking event at FAST, where wheel treads were heated by tread braking. The authors describe the testing and discuss the axial residual stress results in detail, with emphasis on implications for service.

Residual Stress Evaluation of Ni Based Weld Metal Using Neutron Diffraction Method

2006 ◽  
Vol 524-525 ◽  
pp. 697-702 ◽  
Author(s):  
Shinobu Okido ◽  
Hiroshi Suzuki ◽  
K. Saito
Keyword(s):  
Residual Stress ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Neutron Diffraction ◽  
Weld Metal ◽  
Diffraction Method ◽  
Fem Analysis ◽  
Butt Weld ◽  
Stress Evaluation ◽  
Neutron Diffraction Method

Residual stress generated in Type-316 austenitic stainless steel butt-weld jointed by Inconel-182 was measured using a neutron diffraction method and compared with values calculated using FEM analysis. The measured values of Type-316 austenitic stainless steel as base material agreed well with the calculated ones. The diffraction had high intensity and a sharp profile in the base metal. However, it was difficult to measure the residual stress at the weld metal due to very weak diffraction intensities. This phenomenon was caused by the texture in the weld material generated during the weld procedure. As a result, this texture induced an inaccurate evaluation of the residual stress. Procedures for residual stress evaluation to solve this textured material problem are discussed in this paper. As a method for stress evaluation, the measured strains obtained from a different diffraction plane with strong intensity were modified with the ratio of the individual elastic constant. The values of residual stress obtained using this method were almost the same as those of the standard method using Hooke’s law. Also, these residual stress values agreed roughly with those from the FEM analysis. This evaluation method is effective for measured samples with a strong texture like Ni-based weld metal.

Damage Evolution of the Interphase on C/SiC Composites with CZM Method

2012 ◽  
Vol 166-169 ◽  
pp. 2847-2850
Author(s):  
Yan Jun Chang ◽  
Zhuo Li ◽  
Ke Shi Zhang
Keyword(s):  
Residual Stress ◽  
Damage Evolution ◽  
Fem Analysis ◽  
Matrix Crack ◽  
Thermal Residual Stress ◽  
Analysis Model ◽  
Initial Matrix ◽  
Thermal Residual Stresses ◽  
Initiation And Propagation ◽  
Sic Composites

Considering thermal residual stress and initial matrix crack, the cylinder FEM analysis model for C/SiC tow was established. The cohesive element and damage criterions were introduced to simulation the initiation and propagation of interphase crack processes of C/SiC composites. The thermal residual stresses release with the initial matrix crack and the cracking on interphase. The interphase crack length was dominated by the performance of interphase. Analysis demonstrated that the CZM model can simulate well the thermal residual stress and the delamination of the interphase.

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