(a) The BCC iron has a density of 7882 kg/m³ and the lattice parameter of 0.287 nm when hydrogen atoms are introduced at interstitial positions. Evaluate (i) the atomic fraction of hydrogen atoms (ii) the number of unit cells on average that contain hydrogen atoms (b) The strength values of a tungsten-tantalum alloy and its related properties are shown in the table below: Grain diameter (mm) Strength (MPa) 0.071 140 0.110 134 0.203 129 0.314 126 Determine (i) the constants in the Hall-Petch equation. (ii) the grain size required to obtain strength of 300 MPa.

(a) The BCC iron has a density of 7882 kg/m³ and the lattice parameter of 0.287 nm when hydrogen atoms are introduced at interstitial positions. Evaluate (i) the atomic fraction of hydrogen atoms (ii) the number of unit cells on average that contain hydrogen atoms (b) The strength values of a tungsten-tantalum alloy and its related properties are shown in the table below: Grain diameter (mm) Strength (MPa) 0.071 140 0.110 134 0.203 129 0.314 126 Determine (i) the constants in the Hall-Petch equation. (ii) the grain size required to obtain strength of 300 MPa.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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