The flow stress of a coarse-grained dilute copper alloy increased from 2 to 55 MPa when the dislocation density was increased from a low value of 10² cm² via cold working to a modest value of 100 cm². Calculate the flow stress for this alloy when heavy cold working introduces a dislocation density of 10¹2 cm². An equation similar to the Hall-Petch equation has been proposed for dislocations, and is: To ka √Paist + Tflow where Tflow is the flow stress (i.e., the force per unit area necessary to get plastic deformation), Pdisi is the dislocation density (the dislocation line length per unit volume). and to and ka are constants for a given material. The easiest way to solve this problem is to put values into this equation twice, subtract one expression from the other, and solve for ka. Then enter your value of k into either original equation to determine To. Keep track of units, and then solve the problem stated above.

The flow stress of a coarse-grained dilute copper alloy increased from 2 to 55 MPa when the dislocation density was increased from a low value of 10² cm² via cold working to a modest value of 100 cm². Calculate the flow stress for this alloy when heavy cold working introduces a dislocation density of 10¹2 cm². An equation similar to the Hall-Petch equation has been proposed for dislocations, and is: To ka √Paist + Tflow where Tflow is the flow stress (i.e., the force per unit area necessary to get plastic deformation), Pdisi is the dislocation density (the dislocation line length per unit volume). and to and ka are constants for a given material. The easiest way to solve this problem is to put values into this equation twice, subtract one expression from the other, and solve for ka. Then enter your value of k into either original equation to determine To. Keep track of units, and then solve the problem stated above.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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