# JNTU IV B.Tech I Semester Supplimentary Examinations, February 2008

JNTU IV B.Tech I Semester Supplimentary Examinations, February 2008

X-RAY METALLOGRAPHY

(Metallurgy & Material Technology)

SET-I

1. Discuss the history of X-radiations. Describe the methods for X-ray production.

2. (a) Draw the following planes and directions in a tetragonal unit cell (001), (011),

(113), [110], [201], [101]. Show cell axes.

(b) Rubidium is a BCC crystal. The angle of diffraction for (321) set of planes is at 270 for the first order reflection. The wavelength of X-rays used is 0.0711nm. Calculate the interplanar distance of the planes. What is the atomic radius of Rubidium atom?

3. Write short notes on the following:

(a) Multiplicity factor

(b) Lorentz factor.

4. (a) Describe how powder photograph is taken?

(b) Describe how powder pattern of Cubic crystals can be analyzed.

5. Giving the principle, Describing the design and with a neat sketch explain the working of focusing Cameras.

6. (a) What is the principle involved in Diffractometre with monochromatic crystal.

(b) With a neat sketch explain the working of above Diffractometre.

7. A Transmission pinhole photograph is made of a sheet of Aluminum 0.5 mm thick With Cu K? radiation. Consider only the (111) reflection which occurs at 2? = 38.40. Imagine the sheet to be divided into four layers, the thickness of each being equal to one fourth of the total thickness. Calculate the fraction of the total diffracted energy for each layer.

8. Compare and Contrast Coherent and Incoherent radiation.