1-20 of 156 Search Results for

atomic structure

Sort by
Series: ASM Handbook Archive
Volume: 11
Publisher: ASM International
Published: 01 January 2002
DOI: 10.31399/asm.hb.v11.a0003543
EISBN: 978-1-62708-180-1
... of an overload failure. It also presents examples of thermally and environmentally induced embrittlement effects that can alter the overload fracture behavior of metals. atomic structure brittle cracking crack propagation crystalline structure ductile cracking ductility environmentally induced...
Image
Published: 15 May 2022
Fig. 8 Polymer structure. The spheres represent the repeating units of the polymer chain, not individual atoms. Source: Ref 8 More
Image
Published: 15 May 2022
Fig. 7 Representative structures of thermoset plastics. R represents one or more carbon atoms. Source: Ref 21 More
Image
Published: 15 May 2022
Fig. 2 Schematic diagrams of (a) halloysite crystalline structure and (b) halloysite nanotubes. Images of halloysite nanotubes by (c) transmission electron microscopy (TEM) and (d) atomic force microscopy (AFM). Source: Ref 17 More
Series: ASM Handbook
Volume: 11
Publisher: ASM International
Published: 15 January 2021
DOI: 10.31399/asm.hb.v11.a0006770
EISBN: 978-1-62708-295-2
... crystal of known material that has been selected on the basis of its atomic structure and lattice spacing. The angle of the incoming x-rays that are incident upon the crystal is changed in a serial manner, and as the crystal sweeps through the entire range, x-rays are diffracted into a detector...
Series: ASM Handbook
Volume: 11B
Publisher: ASM International
Published: 15 May 2022
DOI: 10.31399/asm.hb.v11B.a0006925
EISBN: 978-1-62708-395-9
... 51 12.2 Source: Ref 5 Unlike either metallic or ionic bonds, covalent bonds are very directional in character. This means that the atoms in the molecule are oriented with fixed bond angles between atoms in a polymer molecule (dictated by the chemical and electronic structures...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.homegoods.c0049838
EISBN: 978-1-62708-222-8
... microscopy of the contacts revealed perturbed regions in which the composition apparently underwent a change during the failure, as suggested by compositional (atomic number) contrast in the SEM images. The SEM images, which were obtained in the electron probe microanalyzer, in fact served as a guide...
Series: ASM Handbook
Volume: 11B
Publisher: ASM International
Published: 15 May 2022
DOI: 10.31399/asm.hb.v11B.a0006915
EISBN: 978-1-62708-395-9
... 2 – 7 Composition Submolecular Structure Most engineering plastics are based on organic (carbon-base) polymers. Table 2 lists common atoms found in plastics and gives both the electronegativity (relative tendency to attract electrons) of the atom and the number of bonds typically...
Series: ASM Handbook
Volume: 11
Publisher: ASM International
Published: 15 January 2021
DOI: 10.31399/asm.hb.v11.a0006778
EISBN: 978-1-62708-295-2
... is that properties are a function of structure and structure is a function of processing. At the atomic structure level, individual atoms exhibit differences in the number of electrons in the various electron shells, resulting in different types of bonding and bond strength. Bonding can be covalent (strong...
Series: ASM Handbook
Volume: 11B
Publisher: ASM International
Published: 15 May 2022
DOI: 10.31399/asm.hb.v11B.a0006943
EISBN: 978-1-62708-395-9
... Abstract This article discusses the operating principles, advantages, and limitations of scanning electron microscopy, atomic force microscopy, x-ray photoelectron spectroscopy, and secondary ion mass spectroscopy that are used to analyze the surface chemistry of plastics. atomic force...
Series: ASM Handbook Archive
Volume: 11
Publisher: ASM International
Published: 01 January 2002
DOI: 10.31399/asm.hb.v11.a0003534
EISBN: 978-1-62708-180-1
... structure of the surfaces under study. Most of these techniques are based on bombarding the surface with photons, x-rays, ions, neutrons, or electrons and analyzing the radiation emitted and/or reflected from the surface. Other techniques use other interactions, such as physical probing of the surface...
Series: ASM Handbook Archive
Volume: 11
Publisher: ASM International
Published: 01 January 2002
DOI: 10.31399/asm.hb.v11.a0003533
EISBN: 978-1-62708-180-1
... structure of various metals is imaged using secondary and backscattered electrons. While the layers can be clearly seen in the etched sample, it is only in the BSE image that the large difference in atomic number of the components is discerned. If a polished, homogeneous, single-phase sample were placed...
Series: ASM Handbook Archive
Volume: 11
Publisher: ASM International
Published: 01 January 2002
DOI: 10.31399/asm.hb.v11.a0003552
EISBN: 978-1-62708-180-1
... the material by lowering the bond strength between metal atoms. This theory is the one that is most applicable to the type of hydrogen embrittlement generally found in newly processed parts that crack during shipping or are found cracked at some point during the assembly process. Grain boundaries of steel...
Series: ASM Handbook
Volume: 11
Publisher: ASM International
Published: 15 January 2021
DOI: 10.31399/asm.hb.v11.a0006784
EISBN: 978-1-62708-295-2
.... The decohesion theory ( Ref 2 ) holds that dissolved hydrogen tends to migrate toward regions of hydrostatic (often termed as triaxial) tensile stress and weakens the material by lowering the bond strength between metal atoms. This theory is the one that is most applicable to the type of hydrogen embrittlement...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.steel.c9001238
EISBN: 978-1-62708-232-7
... supposedly did not exceed 1050 deg C. Structural observations indicated a special case of internal oxidation. The required conditions for this were apparently provided by the moist hydrogen atmosphere of the annealing furnace, in which the chromium was oxidized, while the oxides of iron and nickel were...
Series: ASM Handbook
Volume: 11
Publisher: ASM International
Published: 15 January 2021
DOI: 10.31399/asm.hb.v11.a0006769
EISBN: 978-1-62708-295-2
... as a function of atomic number Due to their low energy, secondary electrons are typically attracted to a photomultiplier/scintillator detector by placing a positive bias on the detector. For each pixel where the beam interacts with the sample, a signal is collected, processed, and displayed...
Series: ASM Handbook
Volume: 11B
Publisher: ASM International
Published: 15 May 2022
DOI: 10.31399/asm.hb.v11B.a0006922
EISBN: 978-1-62708-395-9
... a material to a part and/or mold design for which it is not suited. Materials commonly are used to solve structural shortcomings or processing issues. The most successful parts result from leveraging the properties of the material together with its geometric features, all the while understanding how molding...
Series: ASM Handbook
Volume: 11
Publisher: ASM International
Published: 15 January 2021
DOI: 10.31399/asm.hb.v11.a0006759
EISBN: 978-1-62708-295-2
... be employed for alloy verification, or the results must indicate the potential that various alloys match the chemistry of the part. An example is the overlapping chemistry of the structural carbon steel ASTM A36 and the high-strength, low-alloy steel (HSLA) ASTM A572. The A36 structural steel has chemical...
Series: ASM Failure Analysis Case Histories
Volume: 2
Publisher: ASM International
Published: 01 December 1993
DOI: 10.31399/asm.fach.v02.c9001364
EISBN: 978-1-62708-215-0
... for evaluation of microstructure. Figure 4 shows the typical microstructure observed in the aluminum pieces. The structure consists of dendrites of primary aluminum with inter-dendritic silicon particles and porosity. The porosity (shrinkage cavities) is most likely caused by solidification shrinkage. Fig...
Series: ASM Failure Analysis Case Histories
Volume: 3
Publisher: ASM International
Published: 01 December 2019
DOI: 10.31399/asm.fach.v03.c9001813
EISBN: 978-1-62708-241-9
... effect on material properties and structures. In general, the more randomly distributed the nodules, the less effect they have on structural integrity. In the cases examined, the nodules were found to be organized in planar arrays, indicating they might have an effect on material properties. Closer...