Question

Match the concepts listed in Column I with the associated terms listed in Column II.

Column I	Column II
(P) Paris Law	(1) Creep
(Q) Schmid Factor	(2) Fatigue
(R) Larson-Miller Parameter	(3) Dynamic Strain Aging
(S) Portevin-Le Chatelier Effect	(4) Critical Resolved Shear Stress

• A. P-3, Q-1, R-2, S-4
• B. P-2, Q-4, R-1, S-3
• C. P-2, Q-4, R-3, S-1
• D. P-1, Q-3, R-2, S-4

Hint:

Match each named law or parameter to the single mechanical-behavior phenomenon it is used to predict.

Answer 1

The Correct Option is B

Step 1: Recall what each named concept describes.
Each item in Column I is a named law, parameter or effect from mechanical metallurgy. We match each one to the phenomenon it is actually used to describe or predict.

Step 2: Match P (Paris Law).
The Paris Law gives the rate of fatigue crack growth per loading cycle, \(da/dN\), as a function of the stress intensity factor range \(\Delta K\), written \(da/dN = C(\Delta K)^m\). This law belongs entirely to the study of fatigue, so P matches entry (2), Fatigue.

Step 3: Match Q (Schmid Factor).
The Schmid factor relates the applied uniaxial stress to the resolved shear stress on a slip plane along a slip direction. Slip begins once this resolved shear stress reaches the Critical Resolved Shear Stress (CRSS), and the Schmid factor is exactly the geometric term used to compute it. So Q matches entry (4), Critical Resolved Shear Stress.

Step 4: Match R (Larson-Miller Parameter).
The Larson-Miller Parameter combines temperature and rupture time into a single number used to extrapolate long-term creep-rupture behavior from shorter, high-temperature test data. This is a creep design tool, so R matches entry (1), Creep.

Step 5: Match S (Portevin-Le Chatelier Effect).
This effect is the serrated, jerky flow seen on the stress-strain curve of some alloys at certain temperatures and strain rates, caused by repeated pinning and unpinning of moving dislocations by diffusing solute atoms. This repeated pinning process is called dynamic strain aging, so S matches entry (3), Dynamic Strain Aging.

Step 6: Combine and check against the options.
The complete match is P-2, Q-4, R-1, S-3, which is exactly option (B).
\[ \boxed{P\text{-}2,\ Q\text{-}4,\ R\text{-}1,\ S\text{-}3} \]