Application Of Electron Microscopy To Automotive Finish Defect Analysis

1990 ◽  
Vol 48 (2) ◽  
pp. 258-259
Author(s):  
Martin J. Mahon ◽  
Patrick W. Keating ◽  
John T. McLaughlin
Keyword(s):  
Electron Microscopy ◽  
Zero Tolerance ◽  
Polymeric Materials ◽  
Plant Management ◽  
Defect Analysis ◽  
X Ray ◽  
Root Cause ◽  
Cutting Out ◽  
Foreign Materials ◽  
Automotive Finish

Coatings are applied to appliances, instruments and automobiles for a variety of reasons including corrosion protection and enhancement of market value. Automobile finishes are a highly complex blend of polymeric materials which have a definite impact on the eventual ability of a car to sell. Consumers report that the gloss of the finish is one of the major items they look for in an automobile.With the finish being such an important part of the automobile, there is a zero tolerance for paint defects by auto assembly plant management. Owing to the increased complexity of the paint matrix and its inability to be “forgiving” when foreign materials are introduced into a newly applied finish, the analysis of paint defects has taken on unparalleled importance. Scanning electron microscopy with its attendant x-ray analysis capability is the premier method of examining defects and attempting to identify their root cause.Defects are normally examined by cutting out a coupon sized portion of the autobody and viewing in an SEM at various angles.

Characterization of “Stickies” Polymeric Contaminants in Recycle Pulp Slurries by Optical Fluorescence and Scanning Electron Microscopy.

1997 ◽  
Vol 3 (S2) ◽  
pp. 1247-1248
Author(s):  
R. M. Fisher ◽  
J. Holbery ◽  
Barbara Reine
Keyword(s):  
Electron Microscopy ◽  
Fine Particles ◽  
Polymeric Materials ◽  
Measuring Instruments ◽  
Paper Machine ◽  
X Ray ◽  
Optical Fluorescence ◽  
Thermal Analysis Techniques ◽  
Physical And Chemical

A major problem now hampering increased recycling of old cardboard containers (OCC), is the presence of significant amounts of polymeric materials such as adhesives, tapes, labels and wax which enter the pulp process stream along with the cardboard and paper that was collected for recycling. Many of these materials contain very fine particles of inorganic fillers and pigments. These various contaminant constituents combine in some, as yet unknown, manner to form an extremely gummy material that deposits on paper machine surfaces and sticks tenaciously (hence the term “Stickies”). The sticky blobs are very difficult to remove and increases machine downtime and maintenance costs as well as causing blemishes on the finished container board product Light optical image analysis, UV fluorescence, FTIR and electron microscopy are being used in consort with particle size measuring instruments, TGS and DSC thermal analysis techniques, FTIR infra-red spectroscopy as well as XRF (x-ray fluorescence spectroscopy ), XPS (x-ray photo emission spectroscopy) and classical contact angle determination methods as part of a broad program to characterize the physical and chemical nature of stickies in pulp slurries with the goal of removing them or alleviating their pronounced tendency to deposit on machinery and paper products.

The Combination of Electron Microscopy, Raman Microscopy and Energy Dispersive X‐Ray Spectroscopy for the Investigation of Polymeric Materials

2019 ◽  
Vol 384 (1) ◽  
pp. 1800237 ◽  
Author(s):  
Ruth Schmidt ◽  
Harald Fitzek ◽  
Manfred Nachtnebel ◽  
Claudia Mayrhofer ◽  
Hartmuth Schroettner ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Polymeric Materials ◽  
Raman Microscopy ◽  
Energy Dispersive ◽  
X Ray

Characterization of Triangular-Defects in 4° off 4H-SiC Epitaxial Wafers by Synchrotron X-Ray Topography and by Transmission Electron Microscopy

2012 ◽  
Vol 717-720 ◽  
pp. 363-366 ◽  
Author(s):  
Tamotsu Yamashita ◽  
Kenji Momose ◽  
Daisuke Muto ◽  
Yoshiki Shimodaira ◽  
Kuniaki Yamatake ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Basal Plane ◽  
X Ray ◽  
Transmission Electron ◽  
Foreign Materials

We report our investigation results on triangular-defects formed on 4deg. off 4H-SiC epi- taxial wafers. Triangular-defects that had neither down-falls nor basal-plane dislocations previously reported as origins of triangular-defects at the tips of triangle were investigated by TEM. Our TEM results revealed that foreign materials contamination that were different from well-known down- -falls in size and in composition caused one of the defect formations and abnormal domain forma- tions were implied to occur and thought to relate to defect formations. We also report that several types of microstructure existed in the isosceles of defect during dislocation analyses around triangular-defects by X-ray topography.

Failure Investigation and Analysis of Abnormal Capacitance of Accelerometer After ICP Release

2008 ◽  
Author(s):  
Ping An ◽  
Yandong He ◽  
Shitao Wang ◽  
Yanping Bai ◽  
Yilong Hao
Keyword(s):  
Electron Microscopy ◽  
Test Results ◽  
X Ray ◽  
Root Cause ◽  
Capacitive Accelerometer ◽  
Icp Etching ◽  
Failure Investigation ◽  
Transmission Electron ◽  
Static Capacitance ◽  
Root Cause Failure Analysis

An abnormal capacitance case of capacitive accelerometer after inductive coupled plasma (ICP) release was investigated to solve the failure problem. scanning electron microscopy (SEM)/transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDX), X-Ray transmission inspection, epoxy resin filling/polishing were used to identify the possible root cause. Failure analysis results confirmed that abnormal capacitance occurred by some connecting combs. Based on the results of three ways to analysis, it was concluded that the abnormal capacitance was not due to the contamination between combs of accelerometer and the substrate, but due to the connection between some combs caused by the ICP etching ununiformity. The static capacitance and resistance test results also testified this conclusion.

scholarly journals Electron Probe X-Ray Microanalysis in Pathology and Research

2013 ◽  
Vol 19 (S4) ◽  
pp. 1-2 ◽  
Author(s):  
A. LeFurgey ◽  
P. Ingram
Keyword(s):  
Electron Microscopy ◽  
Electron Probe ◽  
Clinical Medicine ◽  
Analytical Electron Microscopy ◽  
Urinary Calculi ◽  
Energy Dispersive ◽  
X Ray ◽  
Analytical Electron ◽  
Foreign Materials ◽  
Tissue Reactions

A variety of frequently encountered clinical problems lend themselves readily to investigation by analytical electron microscopy. e.g., a combination of scanning or transmission electron microscopy and energy dispersive x-ray microanalysis. The most common application is identification of xenobiotics or exogenous substances, such as localization and quantitation of inorganic particulates in lung tissues in patients with pneumoconiosis; identification of foreign materials within granulomas; and analysis of foreign bodies. Electron probe X-ray microanalysis (EPXMA) is also useful in the study of tissue reactions to various surgical implants of foreign materials. A variety of metals and other elements may be detected with energy dispersive X-ray analysis, including copper in tissues of patients with Wilson’s disease, thorium and gadolinium in patients injected with radiographic contrast agents (Figure 1), or gold in patients treated with long-term chrysotherapy. Endogenous particulates such as urinary calculi (Figure 2), gallstones, intraarticular and periarticular crystalline deposits in patients with rheumatic disease, dystrophic or metastatic calcifications, and hemosiderin may be analyzed rapidly and efficiently by means of EDX. Certain organometallic drugs such as amiodarone (iodine) or sodium stibogluconate (antimony) may also be detected in human tissues. Analytical electron microscopy has been a useful adjunct to forensic pathology for many years in diverse areas such as identification of trace evidence constituents or detection of arsenic or lead in victims with heavy metal poisoning. The detailed elucidation of anatomic, physiologic, and pathologic conditions provided by analytical electron microscopy is a useful diagnostic and investigative tool in clinical medicine; the analytical results often have diagnostic, therapeutic, and/or medicolegal implications. This imaging technology should grow in utility in the future as it is complemented by other techniques such as mass spectrometry, and laser Raman and infrared microspectroscopy.

Quaternary structure of Limulus polyphemus hemocyanin

1978 ◽  
Vol 36 (2) ◽  
pp. 176-177
Author(s):  
T. Wichertjes ◽  
E.J. Kwak ◽  
E.F.J. Van Bruggen
Keyword(s):  
Electron Microscopy ◽  
Functional Properties ◽  
Horseshoe Crab ◽  
Temperature Jump ◽  
Quaternary Structure ◽  
Crystallographic Analysis ◽  
Limulus Polyphemus ◽  
Oxygen Binding ◽  
X Ray ◽  
Intact Molecule

Hemocyanin of the horseshoe crab (Limulus polyphemus) has been studied in nany ways. Recently the structure, dissociation and reassembly was studied using electron microscopy of negatively stained specimens as the method of investigation. Crystallization of the protein proved to be possible and X-ray crystallographic analysis was started. Also fluorescence properties of the hemocyanin after dialysis against Tris-glycine buffer + 0.01 M EDTA pH 8.9 (so called “stripped” hemocyanin) and its fractions II and V were studied, as well as functional properties of the fractions by NMR. Finally the temperature-jump method was used for assaying the oxygen binding of the dissociating molecule and of preparations of isolated subunits. Nevertheless very little is known about the structure of the intact molecule. Schutter et al. suggested that the molecule possibly consists of two halves, combined in a staggered way, the halves themselves consisting of four subunits arranged in a square.

Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

1974 ◽  
Vol 32 ◽  
pp. 514-515
Author(s):  
S. Fujishiro
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
Tensile Strength ◽  
Mechanical Processing ◽  
Ray Method ◽  
X Ray ◽  
Transmission Electron ◽  
Water Quench ◽  
Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

The Resolution and Contrast in Biological Sections Determined by Inelastic and Elastic Scattering

1973 ◽  
Vol 31 ◽  
pp. 224-225
Author(s):  
D. L. Misell
Keyword(s):  
Electron Microscopy ◽  
Adverse Effect ◽  
Elastic Scattering ◽  
Inelastic Scattering ◽  
Amorphous Carbon ◽  
Polymeric Materials ◽  
Chromatic Aberration ◽  
Image Resolution ◽  
Quantitative Estimates ◽  
Elastic Ratio

In the electron microscopy of biological sections the adverse effect of chromatic aberration on image resolution is well known. In this paper calculations are presented for the inelastic and elastic image intensities using a wave-optical formulation. Quantitative estimates of the deterioration in image resolution as a result of chromatic aberration are presented as an alternative to geometric calculations. The predominance of inelastic scattering in the unstained biological and polymeric materials is shown by the inelastic to elastic ratio, I/E, within an objective aperture of 0.005 rad for amorphous carbon of a thickness, t=50nm, typical of biological sections; E=200keV, I/E=16.

Sem Studies of Co-Cr-Mo Surgical Implant Alloy Corrosion Behavior

1982 ◽  
Vol 40 ◽  
pp. 520-521
Author(s):  
Ann Chidester Van Orden ◽  
John L. Chidester ◽  
Anna C. Fraker ◽  
Pei Sung
Keyword(s):  
Electron Microscopy ◽  
Corrosion Behavior ◽  
Anodic Polarization ◽  
Saline Solution ◽  
Saturated Calomel Electrode ◽  
Physiological Saline ◽  
X Ray ◽  
Physiological Saline Solution ◽  
Scanning Electron

The influence of small variations in the composition on the corrosion behavior of Co-Cr-Mo alloys has been studied using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), and electrochemical measurements. SEM and EDX data were correlated with data from in vitro corrosion measurements involving repassivation and also potentiostatic anodic polarization measurements. Specimens studied included the four alloys shown in Table 1. Corrosion tests were conducted in Hanks' physiological saline solution which has a pH of 7.4 and was held at a temperature of 37°C. Specimens were mechanically polished to a surface finish with 0.05 µm A1203, then exposed to the solution and anodically polarized at a rate of 0.006 v/min. All voltages were measured vs. the saturated calomel electrode (s.c.e.).. Specimens had breakdown potentials near 0.47V vs. s.c.e.

Microtubule nucleation sequence studied by time-resolved x-ray scattering and electron microscopy

1983 ◽  
Vol 41 ◽  
pp. 766-767
Author(s):  
Eva-Maria Mandelkow ◽  
Eckhard Mandelkow ◽  
Joan Bordas
Keyword(s):  
Electron Microscopy ◽  
Dynamic Equilibrium ◽  
Time Resolved ◽  
X Ray ◽  
Additional Information ◽  
X Ray Scattering ◽  
Low Concentrations ◽  
Microtubule Growth ◽  
Ray Patterns ◽  
Ray Scattering

When a solution of microtubule protein is changed from non-polymerising to polymerising conditions (e.g. by temperature jump or mixing with GTP) there is a series of structural transitions preceding microtubule growth. These have been detected by time-resolved X-ray scattering using synchrotron radiation, and they may be classified into pre-nucleation and nucleation events. X-ray patterns are good indicators for the average behavior of the particles in solution, but they are difficult to interpret unless additional information on their structure is available. We therefore studied the assembly process by electron microscopy under conditions approaching those of the X-ray experiment. There are two difficulties in the EM approach: One is that the particles important for assembly are usually small and not very regular and therefore tend to be overlooked. Secondly EM specimens require low concentrations which favor disassembly of the particles one wants to observe since there is a dynamic equilibrium between polymers and subunits.

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