scholarly journals Track Substructure Assessment using Non-Destructive Load Tests. A Portuguese Case Study

2012 ◽  
Vol 53 ◽  
pp. 1129-1138
Author(s):  
F. De Chiara ◽  
D. Pereira ◽  
S. Fontul ◽  
E. Fortunato
Keyword(s):  
Load Tests ◽  
Track Substructure ◽  
Non Destructive

Failure Analysis Case Study of a 1.5 Meter Space Flex Harness

2017 ◽  
Author(s):  
Erick Kim ◽  
Kamjou Mansour ◽  
Gil Garteiz ◽  
Javeck Verdugo ◽  
Ryan Ross ◽  
...  
Keyword(s):  
Failure Analysis ◽  
Failure Modes ◽  
Field Of View ◽  
Area Of Interest ◽  
Air Stream ◽  
Novel Method ◽  
Temperature Controlled ◽  
Non Destructive ◽  
Failure Site

Abstract This paper presents the failure analysis on a 1.5m flex harness for a space flight instrument that exhibited two failure modes: global isolation resistances between all adjacent traces measured tens of milliohm and lower resistance on the order of 1 kiloohm was observed on several pins. It shows a novel method using a temperature controlled air stream while monitoring isolation resistance to identify a general area of interest of a low isolation resistance failure. The paper explains how isolation resistance measurements were taken and details the steps taken in both destructive and non-destructive analyses. In theory, infrared hotspot could have been completed along the length of the flex harness to locate the failure site. However, with a field of view of approximately 5 x 5 cm, this technique would have been time prohibitive.

scholarly journals Non-destructive handheld XRF study of archaeological composite silver objects—the case study of the late Roman Seuso Treasure

2021 ◽  
Vol 13 (5) ◽  
Author(s):  
Viktória Mozgai ◽  
Bernadett Bajnóczi ◽  
Zoltán May ◽  
Zsolt Mráv
Keyword(s):  
Fluorescence Analysis ◽  
The Body ◽  
High Quality ◽  
X Ray ◽  
Composite Objects ◽  
Mechanical Attachment ◽  
Non Destructive ◽  
Made In ◽  
Late Roman

AbstractThis study details the non-destructive chemical analysis of composite silver objects (ewers, situlas, amphora and casket) from one of the most significant late Roman finds, the Seuso Treasure. The Seuso Treasure consists of fourteen large silver vessels that were made in the fourth–early fifth centuries AD and used for dining during festive banquets and for washing and beautification. The measurements were systematically performed along a pre-designed grid at several points using handheld X-ray fluorescence analysis. The results demonstrate that all the objects were made from high-quality silver (above 90 wt% Ag), with the exception of the base of the Geometric Ewer B. Copper was added intentionally to improve the mechanical properties of soft silver. The gold and lead content of the objects shows constant values (less than 1 wt% Au and Pb). The chemical composition as well as the Bi/Pb ratio suggests that the parts of the composite objects were manufactured from different silver ingots. The ewers were constructed in two ways: (i) the base and the body were made separately, or (ii) the ewer was raised from a single silver sheet. The composite objects were assembled using three methods: (i) mechanical attachment; (ii) low-temperature, lead-tin soft solders; or (iii) high-temperature, copper-silver hard solders. Additionally, two types of gilding were revealed by the XRF analysis, one with remnants of mercury, i.e. fire-gilding, and another type without remnants of mercury, presumably diffusion bonding.

Corrosion Metal Loss Interaction From In-Line Inspection and How it Can Affect the Calculated Failure Pressure

2012 ◽  
Author(s):  
Lucinda Smart ◽  
Richard McNealy ◽  
Harvey Haines
Keyword(s):  
Field Measurements ◽  
Metal Loss ◽  
Data Correlation ◽  
Failure Pressure ◽  
Industry Standards ◽  
Direct Measurements ◽  
Non Destructive ◽  
Flux Leakage

In-Line Inspection (ILI) is used to prioritize metal loss conditions based on predicted failure pressure in accordance with methods prescribed in industry standards such as ASME B31G-2009. Corrosion may occur in multiple areas of metal loss that interact and may result in a lower failure pressure than if flaws were analyzed separately. The B31G standard recommends a flaw interaction criterion for ILI metal loss predictions within a longitudinal and circumferential spacing of 3 times wall thickness, but cautions that methods employed for clustering of ILI anomalies should be validated with results from direct measurements in the ditch. Recent advances in non-destructive examination (NDE) and data correlation software have enabled reliable comparisons of ILI burst pressure predictions with the results from in-ditch examination. Data correlation using pattern matching algorithms allows the consideration of detection and reporting thresholds for both ILI and field measurements, and determination of error in the calculated failure pressure prediction attributable to the flaw interaction criterion. This paper presents a case study of magnetic flux leakage ILI failure pressure predictions compared with field results obtained during excavations. The effect of interaction criterion on calculated failure pressure and the probability of an ILI measurement underestimating failure pressure have been studied. We concluded a reason failure pressure specifications do not exist for ILI measurements is because of the variety of possible interaction criteria and data thresholds that can be employed, and demonstrate herein a method for their validation.

A Fresh Insight into Film Morphology Measurement Techniques for Advanced Ulsi Manufacturing

1993 ◽  
Vol 309 ◽  
Author(s):  
Seshadri Ramaswami
Keyword(s):  
Grain Size ◽  
Integrated Circuit ◽  
Measurement Techniques ◽  
Film Morphology ◽  
Integrated Circuit Fabrication ◽  
Circuit Fabrication ◽  
Non Destructive ◽  
Fresh Insight ◽  
Insight Into

AbstractA laser based non-destructive technique has been used to study the morphology of sputterdeposited aluminum alloy films. The data emanating from the Therma-wave Imager that makes use of this principle, has been correlated with reflectivity, grain size and micro-roughness of the film. In addition, through the use of a case study, this paper demonstrates the utility of this application as an in-line monitor in an integrated circuit fabrication line.

In-Service Cracking/Leak at Bottom-Side Repaired Dent

2020 ◽  
Author(s):  
Gregory T. Quickel ◽  
Joseph Bratton ◽  
William A. Bruce
Keyword(s):  
Laser Scanning ◽  
Current Knowledge ◽  
Service Failure ◽  
Fatigue Behavior ◽  
Crack Identification ◽  
Repair Method ◽  
Cracking Mechanisms ◽  
Bottom Side ◽  
Non Destructive

Abstract Pipeline operators are often faced with excavating deformations caused by bottom-side indenters (e.g., rock dents). These dents are typically constrained by the rock, but during excavation, after the rock is removed, the dent is no longer constrained. Many operators have felt that it is prudent to perform in-the-ditch (ITD) non-destructive examination (NDE) techniques, such as liquid penetrant testing (LPT) and magnetic particle inspection (MPI), to determine if external cracking is present so that an appropriate repair method can be selected. Unfortunately, these external surface NDE methods do not identify the presence of internal cracking. Recent research [1], along with metallurgical analyses of cracks at bottom-side dents, demonstrates that the fatigue behavior of constrained dents is different than that of unconstrained dents, and that identifying the correct crack mechanism can be difficult. The paper discusses cracking mechanisms (e.g., stress corrosion cracking, fatigue, etc.) at bottom-side dents, ITD crack identification methods, differences between constrained and non-constrained dents, repair methods for dents, and presents a case study that uses NDE (MPI, unconventional LPT, and laser scanning) and destructive techniques (metallography, fractography, and hardness testing) to determine the metallurgical cause of a failure. The case study involves a pre-formed composite sleeve system that was used to repair dents in which correct installation procedures were followed but ultimately resulted in a delayed in-service failure. In hindsight, if ITD NDE methods were chosen based on our current knowledge of recent research, the operator may have been aware of the presence of cracking and selected a different repair method, and therefore would have likely prevented an in-service failure. This paper provides a case study to help increase awareness regarding how to properly evaluate cracking in dents. Operators should ensure that their excavation and repair procedures are updated to reflect the most current industry knowledge to help prevent a similar failure.

X-ray Advances in Support of Advanced Packaging – Today and Tomorrow

2018 ◽  
Vol 2018 (1) ◽  
pp. 000409-000414
Author(s):  
David Bernard
Keyword(s):  
Heat Dissipation ◽  
X Ray ◽  
Destructive Test ◽  
Heat Transfer Efficiency ◽  
Advanced Packaging ◽  
History Of ◽  
Production Output ◽  
2D And 3D ◽  
Non Destructive

Abstract As advanced packaging continues to develop to support novel and emerging technologies, the need for, ideally non-destructive, test and inspection continues to be vital to ensure the quality and assurance of functionality, wherever the package may go. This is made ever more difficult as the package complexity increases, whilst the feature sizes within continue to decrease. X-ray technology has long been an important part of the non-destructive inspection protocol over the history of advanced packaging and will continue to need to play a more important part in the future. This paper will review the advances made in both 2D and 3D X-ray inspection over recent years and the new opportunities that are now starting to be available, especially in 3D, or CT, inspection, that will enable this 120-year-old technology to remain relevant to and supportive of the needs of advanced packaging. To highlight the above, a case study will be presented on the faults that 2D and CT X-ray analysis can find in LEDs during their manufacture. LEDs are a good example of the remarkable developments in packaging and technology over the last 20 years, where the use of higher powers, smaller sized features and increased reliability requirements intensify the need for higher quality, more consistent production output. Flaws cannot be accepted, especially as higher usage powers mean higher operating temperatures which, in turn, then requires very good thermal conductivity in the package to move heat away from key areas. Without good heat dissipation then heat stresses at the interfaces can cause delamination or die fractures, so reducing LED lifetimes. The presence of voids, particularly at the die to package interface, creates air gaps that reduces heat transfer efficiency. As many LEDs are potted, or encapsulated, the only non-destructive test option to check for voiding and other faults is by using 2D and CT X-ray analysis.

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