QUESTION 7
As a forensic materials expert – you have been asked to identify a metallic powder found on the clothing of someone suspected of fabricating an incendiary device used in an armed robbery.
The suspect suggests that the powder is tungsten – which he uses a lot in his line of work. The police believe that the powder is part of a chromium/silver/nickel mixture often used in such devices. Armed with the following information from an X-ray powder diffraction analysis – what can you conclude?
Using Cu ka radiation of 0.1542nm, three large diffraction peaks were observed at 44.4°, 64.6° and 81.7°.

QUESTION 9 – Crystallographic transformation
On cooling from the molten state, titanium solidifies into a BCC lattice structure. However, on cooling to below 880°C, a change occurs whereby the crystal structure transforms into an HCP structure. Assuming the number of atoms remains constant and that the lattice parameters are as shown below, calculate the volume change associated with this transformation.
For the BCC lattice: a = 3.32Å
For the HCP lattice: a = 2.956 Å and c = 4.683 Å
Titanium is a commonly used metal in engineering structures. Explain why your findings above should be cause for concern if these engineering structures are to be used at high temperatures.

Posted Date: 3/25/2013 9:14:33 PM | Location : Australia

Ask an Expert

Related Discussions:- ENGINEERING SCIENCE, Assignment Help, Ask Question on ENGINEERING SCIENCE, Get Answer, Expert's Help, ENGINEERING SCIENCE Discussions

Write discussion on ENGINEERING SCIENCE
Your posts are moderated

Write your message here..

Related Questions

Capital management solutions, Objective of corporate financing Corporat... Objective of corporate financing Corporate finance control is a division of financial that refers to the control of money of an organization. The attention of corporate financi

Pn junction diode, what is the effect of temperature on pn junction diode o... what is the effect of temperature on pn junction diode of component

Fire evacuation - railway inspections, Fire evacuation - Railway inspection... Fire evacuation - Railway inspections: Fire evacuation signals should be given by voice messages and these must be easily understood by the occupants. The expected populati

Jfet operation - junction, JFET OPERATION Figure shows the operati... JFET OPERATION Figure shows the operation of a JFET. The JUGFET has a physical structure that can be represented by the diagram shown in Figure. In Figure, if the N-Ty

Gas metal arc welding (gmaw), Gas metal arc welding (GMAW) is performed by ... Gas metal arc welding (GMAW) is performed by using direct current reverse polarity as it gives both good cleaning action and fast filler metal deposition rates. A rather high weldi

Shrinkage cavities casting defects, Q.   Discuss briefly the causes and rem... Q.   Discuss briefly the causes and remedies of Shrinkage cavities casting defects.                                                 OR  Why shrinkage cavities are caus

Manual override relays, Manual override relays: When the manual-overrid... Manual override relays: When the manual-override relays are not energised, this current flows through brushes riding on slip rings mounted on the propeller spinner bulkhead and

Instruction set, compare zero- one- two- and three-address machines by writ... compare zero- one- two- and three-address machines by writing programs to compute X=(A+B*C)/(D-E*F)

Networking engineering, I need 2 assignments on Monday. I need 2 assignments on Monday.

Aerodynamics-influence on transition, Influence on transition Reynold... Influence on transition Reynolds number - relates importance of viscousforces (relative to inertia) Lower Re - molecular diffusion more important; disturbances damped out