Problem 4.24 30 Components subjected to large contact forces (e.g., brake disks) are often made of high- grade steel coated with a thin film of a very hard material, such as diamond. A common test to assess the mechanical properties (hardness, elastic moduli, etc.) of the coating is the nanoindentation test, which consists of making a controlled dent in the film using a nail-like object, called an indentor. During the test, the force applied to the indentor and the indentation depth are measured. The graph shows the curves interpolating the loading and unloading data for a diamond film on steel. Since the unloading curve does not go back to the origin of the plot, the film is permanently deformed during the indentation process. Determine the energy lost to permanent deformation if the indentation force is given by Unloading 25 20 Loading 15 10 20 40 60 80 100 120 during loading. 300-145x+ 18x² during unloading. where F is expressed in uN and the indentation depth x is given in nm. Indentation Depth (nm) Fi = Figure P4.24 Indentation Force (10-4 N)

Problem 4.24 30 Components subjected to large contact forces (e.g., brake disks) are often made of high- grade steel coated with a thin film of a very hard material, such as diamond. A common test to assess the mechanical properties (hardness, elastic moduli, etc.) of the coating is the nanoindentation test, which consists of making a controlled dent in the film using a nail-like object, called an indentor. During the test, the force applied to the indentor and the indentation depth are measured. The graph shows the curves interpolating the loading and unloading data for a diamond film on steel. Since the unloading curve does not go back to the origin of the plot, the film is permanently deformed during the indentation process. Determine the energy lost to permanent deformation if the indentation force is given by Unloading 25 20 Loading 15 10 20 40 60 80 100 120 during loading. 300-145x+ 18x² during unloading. where F is expressed in uN and the indentation depth x is given in nm. Indentation Depth (nm) Fi = Figure P4.24 Indentation Force (10-4 N)

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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