Engineering Board Exam Reviewer · Engineering Materials · hard
Using the Hall–Petch equation y = 0 + ky d-1/2 with 0 = 70 MPa and ky = 0.74 MPa · sqrt(m), what is the yield strength for a grain diameter of 0.025 mm?
- 218.0 MPa
- 99.6 MPa
- 74.68 MPa
- 148.0 MPa
Answer
A. 218.0 MPa
Solution
y = 70 + 0.74/ 2.5 × 10-5 = 70 + 148.0 = 218.0 MPa.
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