MCQOPTIONS
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MCQOPTIONS
This section includes 5 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Metallurgy Questions and Answers knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The stress intensity factor at local crack tip is proportional to __________ |
| A. | length of crack |
| B. | half-length of crack |
| C. | square of half-length of the crack |
| D. | square root of half-length of the crack |
| Answer» E. | |
| 2. |
The unit of crack extension force δc is ____________ |
| A. | N m |
| B. | N m-1 |
| C. | N m2 |
| D. | N m-2 |
| Answer» C. N m2 | |
| 3. |
The fracture stress according to Irwin’s modification is given as ________ |
| A. | (Eδc/πa)1/2 |
| B. | (Eδc/πa) |
| C. | (Eδc/2πa)1/2 |
| D. | (Eδc/2πa) |
| Answer» B. (Eδc/πa) | |
| 4. |
The young’s modulus of the steel is 600 MPa, and the plastic stress required to extend the crack is 50*10-9, and the initial crack length is 2 microns. Find the fracture stress required to crack the material? |
| A. | 15 MPa |
| B. | 50 MPa |
| C. | 15 GPa |
| D. | 10 MPa |
| Answer» B. 50 MPa | |
| 5. |
The fracture stress according to Orowan’s theory of brittle fracture is __________ (where E is Yong’s modulus, ϒp is the plastic work required to extend the crack wall of the length 2a). |
| A. | (Eϒp/a)1/2 |
| B. | (Eϒp/a) |
| C. | (Eϒp/2a)1/2 |
| D. | (Eϒp/2a) |
| Answer» B. (Eϒp/a) | |