MCQOPTIONS
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MCQOPTIONS
This section includes 11 Mcqs, each offering curated multiple-choice questions to sharpen your Powder Metallurgy knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
According to ______, there are six stages of sintering. |
| A. | Schroter |
| B. | Nabarro and Herring |
| C. | Kuczynsky |
| D. | Hutteg |
| Answer» E. | |
| 2. |
The expression for the number of vacant site N is given by ________ |
| A. | N=N<sub>0</sub> (e^{ frac{-Q}{RT}} ) |
| B. | N=N<sub>0</sub> (e^{ frac{-Qt}{RT}} ) |
| C. | N=N<sub>0</sub> (e^{ frac{-QT}{R}} ) |
| D. | N=N<sub>0</sub> (e^{ frac{Q}{RT}} ) |
| Answer» B. N=N<sub>0</sub> (e^{ frac{-Qt}{RT}} ) | |
| 3. |
________ mechanism alters the shape of the neck and particle surface. |
| A. | Viscous flow |
| B. | Volume diffusion |
| C. | Evaporation-condensation |
| D. | Plastic flow |
| Answer» D. Plastic flow | |
| 4. |
Which of the following mechanism does not lead to shrinkage? |
| A. | Viscous flow |
| B. | Surface diffusion |
| C. | Volume diffusion |
| D. | Grain boundary diffusion |
| Answer» C. Volume diffusion | |
| 5. |
The empirical relationship for neck growth rate due to lattice diffusion from dislocation sources is R6= _______, |
| A. | ( Big( frac{4}{9} Big) )K<sub>2</sub>Nx<sup>2</sup>D<sub>v</sub>F(K<sub>2</sub> ( frac{2 epsilon x}{3 gamma_sa}) ) |
| B. | ( Big( frac{4}{9} Big) )Nx<sup>2</sup>D<sub>v</sub>F(K<sub>2</sub> ( frac{3 epsilon x}{2 gamma_sa}) ) |
| C. | ( Big( frac{4}{9} Big) )K<sub>2</sub>Nx<sup>2</sup>D<sub>v</sub>F(K<sub>2</sub> ( frac{3 epsilon x}{2 gamma_sa}) ) |
| D. | ( Big( frac{4}{9} Big) )K<sub>2</sub>Nx<sup>2</sup>D<sub>v</sub>(K<sub>2</sub> ( frac{3 epsilon x}{2 gamma_sa}) ) |
| Answer» D. ( Big( frac{4}{9} Big) )K<sub>2</sub>Nx<sup>2</sup>D<sub>v</sub>(K<sub>2</sub> ( frac{3 epsilon x}{2 gamma_sa}) ) | |
| 6. |
Neck growth rate due to lattice diffusion from sources on the grain boundary is R5= _______ |
| A. | 2D<sub>v</sub> (FK_{1}^2 ) |
| B. | 2D<sub>v</sub> (FK_{1}^3 ) |
| C. | 4D<sub>v</sub> (FK_{1}^2 ) |
| D. | 4D<sub>v</sub> (FK_{2}^2 ) |
| Answer» E. | |
| 7. |
The empirical relationship for neck growth rate due to grain boundary transport from sources on the grain boundary is R4= _______ |
| A. | 4D<sub>B</sub> <sub>B</sub> (FK_{2}^1 )/x |
| B. | 4D<sub>B</sub> <sub>B</sub> (FK_{2}^1 )/x<sup>2</sup> |
| C. | 4D<sub>B</sub> <sub>B</sub> (FK_{2}^1 )/a |
| D. | 4D<sub>B</sub> <sub>B</sub> (FK_{2}^2 )/x |
| Answer» E. | |
| 8. |
The empirical relationship for neck growth rate due to vapor transport from the surface source is R3= _______ |
| A. | P<sub>v</sub>FK<sub>1</sub> ( sqrt{ frac{ Omega}{2 pi rho_{0}kT}} ) |
| B. | P<sub>v</sub>FK<sub>1</sub> ( sqrt{ frac{ Omega}{2 pi rho_{0}T}} ) |
| C. | P<sub>v</sub>FK<sub>1</sub> ( sqrt{ frac{ Omega}{2 rho_{0}kT}} ) |
| D. | P<sub>v</sub>FK<sub>1</sub> ( sqrt{ frac{ Omega T}{2 pi rho_{0}k}} ) |
| Answer» B. P<sub>v</sub>FK<sub>1</sub> ( sqrt{ frac{ Omega}{2 pi rho_{0}T}} ) | |
| 9. |
Neck growth rate due to lattice diffusion from the surface source is R2= _______ |
| A. | 2D<sub>s</sub> (FK_{1}^3 ) |
| B. | 2D<sub>s</sub> (FK_{1}^2 ) |
| C. | 2D<sub>v</sub> (FK_{1}^3 ) |
| D. | 2D<sub>v</sub> (FK_{1}^2 ) |
| Answer» E. | |
| 10. |
Neck growth rate due to surface diffusion from the surface source is R1= _______ |
| A. | 2D<sub>s</sub> <sub>s</sub> (FK_{1}^3 ) |
| B. | 2D<sub>s</sub> <sub>s</sub> (FK_{3}^1 ) |
| C. | 2D<sub>s</sub> (FK_{1}^3 ) |
| D. | 2D<sub>s</sub> <sub>s</sub> (FK_{1}^4 ) |
| Answer» B. 2D<sub>s</sub> <sub>s</sub> (FK_{3}^1 ) | |
| 11. |
Which of the following transport mechanisms can occur for two spheres in contact with one another during sintering? |
| A. | Evaporation-condensation, surface diffusion and volume diffusion |
| B. | Evaporation-condensation, surface diffusion, volume diffusion, volume diffusion of vacancies, and grain boundary diffusion |
| C. | Surface diffusion |
| D. | Volume diffusion |
| Answer» C. Surface diffusion | |